version: 1.0.39

.env

@@ -1,13 +0,0 @@
-ENVIRONMENT=local
-DATABASE_PASSWORD=tIr4TJ0qUwGVM0rlQSe3W7Tgpi33zPbk
-DATABASE_ROLE=agreego_admin
-DATABASE_HOST=127.1.27.4
-DATABASE_PORT=5432
-POSTGRES_PASSWORD=xzIq5JT0xY3F+2m1GtnrKDdK29sNSXVVYZHPKJVh8pI=
-DATABASE_NAME=agreego
-DEV_DATABASE_NAME=agreego_dev
-GITEA_TOKEN=3d70c23673517330623a5122998fb304e3c73f0a
-MOOV_ACCOUNT_ID=69a0d2f6-77a2-4e26-934f-d869134f87d3
-MOOV_PUBLIC_KEY=9OMhK5qGnh7Tmk2Z
-MOOV_SECRET_KEY=DrRox7B-YWfO9IheiUUX7lGP8-7VY-Ni
-MOOV_DOMAIN=http://localhost

.gitignore

@@ -1,2 +1,3 @@
 /target
-/package
+/package
+.env

Cargo.toml

@@ -1,18 +1,23 @@
+[workspace]
+members = [
+    ".",
+    "validator",
+]
+
 [package]
 name = "jspg"
 version = "0.1.0"
-edition = "2021"
+edition = "2024"
 
 [dependencies]
-pgrx = "0.14.0"
+pgrx = "0.15.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-jsonschema = "0.29.1"
 lazy_static = "1.5.0"
-boon = "0.6.1"
+boon = { path = "validator" }
 
 [dev-dependencies]
-pgrx-tests = "0.14.0"
+pgrx-tests = "0.15.0"
 
 [lib]
 crate-type = ["cdylib", "lib"]

GEMINI.md

@@ -0,0 +1,79 @@
+# Gemini Project Overview: `jspg`
+
+This document outlines the purpose of the `jspg` project, its architecture, and the specific modifications made to the vendored `boon` JSON schema validator crate.
+
+## What is `jspg`?
+
+`jspg` is a PostgreSQL extension written in Rust using the `pgrx` framework. Its primary function is to provide fast, in-database JSON schema validation against the 2020-12 draft of the JSON Schema specification.
+
+### How It Works
+
+The extension is designed for high-performance scenarios where schemas are defined once and used many times for validation. It achieves this through an in-memory cache.
+
+1.  **Caching:** A user first calls the `cache_json_schemas(enums, types, puncs)` SQL function. This function takes arrays of JSON objects representing different kinds of schemas within a larger application framework. It uses the vendored `boon` crate to compile all these schemas into an efficient internal format and stores them in a static, in-memory `SCHEMA_CACHE`. This cache is managed by a `RwLock` to allow concurrent reads during validation.
+
+2.  **Validation:** The `validate_json_schema(schema_id, instance)` SQL function is then used to validate a JSONB `instance` against a specific, pre-cached schema identified by its `$id`. This function looks up the compiled schema in the cache and runs the validation, returning a success response or a detailed error report.
+
+3.  **Custom Logic:** `jspg` uses a locally modified (vendored) version of the `boon` crate. This allows for powerful, application-specific validation logic that goes beyond the standard JSON Schema specification, such as runtime-based strictness.
+
+### Error Handling
+
+When validation fails, `jspg` provides a detailed error report in a consistent JSON format, which we refer to as a "DropError". This process involves two main helper functions in `src/lib.rs`:
+
+1.  **`collect_errors`**: `boon` returns a nested tree of `ValidationError` objects. This function recursively traverses that tree to find the most specific, underlying causes of the failure. It filters out structural errors (like `allOf` or `anyOf`) to create a flat list of concrete validation failures.
+
+2.  **`format_errors`**: This function takes the flat list of errors and transforms each one into the final DropError JSON format. It also de-duplicates errors that occur at the same JSON Pointer path, ensuring a cleaner output if a single value violates multiple constraints.
+
+#### DropError Format
+
+A DropError object provides a clear, structured explanation of a validation failure:
+
+```json
+{
+  "code": "ADDITIONAL_PROPERTIES_NOT_ALLOWED",
+  "message": "Property 'extra' is not allowed",
+  "details": {
+    "path": "/extra",
+    "context": "not allowed",
+    "cause": {
+      "got": [
+        "extra"
+      ]
+    },
+    "schema": "basic_strict_test.request"
+  }
+}
+```
+
+-   `code` (string): A machine-readable error code (e.g., `ADDITIONAL_PROPERTIES_NOT_ALLOWED`, `MIN_LENGTH_VIOLATED`).
+-   `message` (string): A human-readable summary of the error.
+-   `details` (object):
+    -   `path` (string): The JSON Pointer path to the invalid data within the instance.
+    -   `context` (any): The actual value that failed validation.
+    -   `cause` (any): The low-level reason from the validator, often including the expected value (`want`) and the actual value (`got`).
+    -   `schema` (string): The `$id` of the schema that was being validated.
+
+---
+
+## `boon` Crate Modifications
+
+The version of `boon` located in the `validator/` directory has been significantly modified to support runtime-based strict validation. The original `boon` crate only supports compile-time strictness and lacks the necessary mechanisms to propagate validation context correctly for our use case.
+
+### 1. Recursive Runtime Strictness Control
+
+-   **Problem:** The `jspg` project requires that certain schemas (specifically those for public `puncs` and global `type`s) enforce a strict "no extra properties" policy. This strictness needs to be decided at runtime and must cascade through the entire validation hierarchy, including all nested objects and `$ref` chains. A compile-time flag was unsuitable because it would incorrectly apply strictness to shared, reusable schemas.
+
+-   **Solution:** A runtime validation option was implemented to enforce strictness recursively. This required several coordinated changes to the `boon` validator.
+
+#### Key Changes
+
+1.  **`ValidationOptions` Struct**: A new `ValidationOptions { be_strict: bool }` struct was added to `validator/src/lib.rs`. The `jspg` code in `src/lib.rs` determines if a validation run should be strict and passes this struct to the validator.
+
+2.  **Strictness Check in `uneval_validate`**: The original `boon` only checked for unevaluated properties if the `unevaluatedProperties` keyword was present in the schema. We added an `else if be_strict` block to `uneval_validate` in `validator/src/validator.rs`. This block triggers a check for any leftover unevaluated properties at the end of a validation pass and reports them as errors, effectively enforcing our runtime strictness rule.
+
+3.  **Correct Context Propagation**: The most complex part of the fix was ensuring the set of unevaluated properties was correctly maintained across different validation contexts (especially `$ref` and nested property validations). Three critical changes were made:
+    -   **Inheriting Context in `_validate_self`**: When validating keywords that apply to the same instance (like `$ref` or `allOf`), the sub-validator must know what properties the parent has already evaluated. We changed the creation of the `Validator` inside `_validate_self` to pass a clone of the parent's `uneval` state (`uneval: self.uneval.clone()`) instead of creating a new one from scratch. This allows the context to flow downwards.
+    -   **Isolating Context in `validate_val`**: Conversely, when validating a property's value, that value is a *different* part of the JSON instance. The sub-validation should not affect the parent's list of unevaluated properties. We fixed this by commenting out the `self.uneval.merge(...)` call in the `validate_val` function.
+    -   **Simplifying `Uneval::merge`**: The original logic for merging `uneval` state was different for `$ref` keywords. This was incorrect. We simplified the `merge` function to *always* perform an intersection (`retain`), which correctly combines the knowledge of evaluated properties from different schema parts that apply to the same instance.
+
+4.  **Removing Incompatible Assertions**: The changes to context propagation broke several `debug_assert!` macros in the `arr_validate` function, which were part of `boon`'s original design. Since our new validation flow is different but correct, these assertions were removed.

flow

@@ -1,8 +1,9 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # Flows
 source ./flows/base
 source ./flows/git
+source ./flows/kube
 source ./flows/packaging
 source ./flows/rust
 
@@ -10,25 +11,10 @@ source ./flows/rust
 POSTGRES_VERSION="17"
 POSTGRES_CONFIG_PATH="/opt/homebrew/opt/postgresql@${POSTGRES_VERSION}/bin/pg_config"
 DEPENDENCIES+=(icu4c pkg-config "postgresql@${POSTGRES_VERSION}")
-CARGO_DEPENDENCIES=(cargo-pgrx==0.14.0)
+CARGO_DEPENDENCIES=(cargo-pgrx==0.15.0)
 GITEA_ORGANIZATION="cellular"
 GITEA_REPOSITORY="jspg"
 
-env() {
-  # Check if GITEA_TOKEN is set
-  if [ -z "$GITEA_TOKEN" ]; then
-    # If not set, try to get it from kubectl
-    GITEA_TOKEN=$(kubectl get secret -n cellular gitea-git -o jsonpath='{.data.token}' | base64 --decode)
-    if [ -z "$GITEA_TOKEN" ]; then
-      error "GITEA_TOKEN is not set and couldn't be retrieved from kubectl" >&2
-      return 2
-    fi
-    export GITEA_TOKEN
-  fi
-
-  success "Environment variables set"
-}
-
 pgrx-prepare() {
   info "Initializing pgrx..."
   # Explicitly point to the postgresql@${POSTGRES_VERSION} pg_config, don't rely on 'which'
@@ -111,11 +97,16 @@ install() {
   fi
 }
 
-test() {
+test-jspg() {
   info "Running jspg tests..."
   cargo pgrx test "pg${POSTGRES_VERSION}" "$@" || return $?
 }
 
+test-validator() {
+  info "Running validator tests..."
+  cargo test -p boon --features "pgrx/pg${POSTGRES_VERSION}" "$@" || return $?
+}
+
 clean() {
   info "Cleaning build artifacts..."
   cargo clean || return $?
@@ -125,22 +116,24 @@ jspg-usage() {
   printf "prepare\tCheck OS, Cargo, and PGRX dependencies.\n"
   printf "install\tBuild and install the extension locally (after prepare).\n"
   printf "reinstall\tClean, build, and install the extension locally (after prepare).\n"
-  printf "test\t\tRun pgrx integration tests.\n"
+  printf "test-jspg\t\tRun pgrx integration tests.\n"
+  printf "test-validator\t\tRun validator integration tests.\n"
   printf "clean\t\tRemove pgrx build artifacts.\n"
 }
 
 jspg-flow() {
   case "$1" in
-    env) env; return $?;; 
-    prepare) base-flow prepare && cargo-prepare && pgrx-prepare; return $?;; 
+    prepare) prepare && cargo-prepare && pgrx-prepare; return $?;; 
     build) build; return $?;; 
     install) install; return $?;; 
     reinstall) clean && install; return $?;; 
-    test) test "${@:2}"; return $?;; 
-    clean) clean; return $?;; 
+    test-jspg) test-jspg "${@:2}"; return $?;;
+    test-validator) test-validator "${@:2}"; return $?;; 
+    clean) clean; return $?;;
     *) return 1 ;;
   esac
 }
 
-register-flow "jspg-flow" "jspg-usage"
+register-flow "jspg-usage" "jspg-flow"
+
 dispatch "$@"

out.txt

@@ -0,0 +1,44 @@
+
+running 23 tests
+    Building extension with features pg_test pg17
+     Running command "/opt/homebrew/bin/cargo" "build" "--lib" "--features" "pg_test pg17" "--message-format=json-render-diagnostics"
+  Installing extension
+     Copying control file to /opt/homebrew/share/postgresql@17/extension/jspg.control
+     Copying shared library to /opt/homebrew/lib/postgresql@17/jspg.dylib
+    Finished installing jspg
+test tests::pg_test_cache_invalid ... ok
+test tests::pg_test_validate_nested_req_deps ... ok
+test tests::pg_test_validate_format_empty_string_with_ref ... ok
+test tests::pg_test_validate_format_normal ... ok
+test tests::pg_test_validate_format_empty_string ... ok
+test tests::pg_test_validate_dependencies ... ok
+test tests::pg_test_validate_dependencies_merging ... ok
+test tests::pg_test_validate_additional_properties ... ok
+test tests::pg_test_validate_enum_schema ... ok
+test tests::pg_test_validate_errors ... ok
+test tests::pg_test_validate_not_cached ... ok
+test tests::pg_test_validate_oneof ... ok
+test tests::pg_test_validate_punc_with_refs ... ok
+test tests::pg_test_validate_property_merging ... ok
+test tests::pg_test_validate_punc_local_refs ... ok
+test tests::pg_test_validate_required_merging ... ok
+test tests::pg_test_validate_required ... ok
+test tests::pg_test_validate_simple ... ok
+test tests::pg_test_validate_root_types ... ok
+test tests::pg_test_validate_strict ... ok
+test tests::pg_test_validate_title_override ... ok
+test tests::pg_test_validate_unevaluated_properties ... ok
+test tests::pg_test_validate_type_matching ... ok
+
+test result: ok. 23 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 7.66s
+
+
+running 0 tests
+
+test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
+
+
+running 0 tests
+
+test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
+

rustfmt.toml

@@ -0,0 +1 @@
+tab_spaces = 2

src/helpers.rs

@@ -0,0 +1,88 @@
+use serde_json::Value;
+use pgrx::JsonB; 
+
+// Simple test helpers for cleaner test code
+pub fn assert_success(result: &JsonB) {
+  let json = &result.0;
+  if !json.get("response").is_some() || json.get("errors").is_some() {
+    let pretty = serde_json::to_string_pretty(json).unwrap_or_else(|_| format!("{:?}", json));
+    panic!("Expected success but got:\n{}", pretty);
+  }
+}
+
+pub fn assert_failure(result: &JsonB) {
+  let json = &result.0;
+  if json.get("response").is_some() || !json.get("errors").is_some() {
+    let pretty = serde_json::to_string_pretty(json).unwrap_or_else(|_| format!("{:?}", json));
+    panic!("Expected failure but got:\n{}", pretty);
+  }
+}
+
+pub fn assert_error_count(result: &JsonB, expected_count: usize) {
+  assert_failure(result);
+  let errors = get_errors(result);
+  if errors.len() != expected_count {
+    let pretty = serde_json::to_string_pretty(&result.0).unwrap_or_else(|_| format!("{:?}", result.0));
+    panic!("Expected {} errors, got {}:\n{}", expected_count, errors.len(), pretty);
+  }
+}
+
+pub fn get_errors(result: &JsonB) -> &Vec<Value> {
+  result.0["errors"].as_array().expect("errors should be an array")
+}
+
+pub fn has_error_with_code(result: &JsonB, code: &str) -> bool {
+  get_errors(result).iter().any(|e| e["code"] == code)
+}
+
+
+pub fn has_error_with_code_and_path(result: &JsonB, code: &str, path: &str) -> bool {
+  get_errors(result).iter().any(|e| e["code"] == code && e["details"]["path"] == path)
+}
+
+pub fn assert_has_error(result: &JsonB, code: &str, path: &str) {
+  if !has_error_with_code_and_path(result, code, path) {
+    let pretty = serde_json::to_string_pretty(&result.0).unwrap_or_else(|_| format!("{:?}", result.0));
+    panic!("Expected error with code='{}' and path='{}' but not found:\n{}", code, path, pretty);
+  }
+}
+
+pub fn find_error_with_code<'a>(result: &'a JsonB, code: &str) -> &'a Value {
+  get_errors(result).iter().find(|e| e["code"] == code)
+    .unwrap_or_else(|| panic!("No error found with code '{}'", code))
+}
+
+
+pub fn find_error_with_code_and_path<'a>(result: &'a JsonB, code: &str, path: &str) -> &'a Value {
+  get_errors(result).iter().find(|e| e["code"] == code && e["details"]["path"] == path)
+    .unwrap_or_else(|| panic!("No error found with code '{}' and path '{}'", code, path))
+}
+
+pub fn assert_error_detail(error: &Value, detail_key: &str, expected_value: &str) {
+  let actual = error["details"][detail_key].as_str()
+    .unwrap_or_else(|| panic!("Error detail '{}' is not a string", detail_key));
+  assert_eq!(actual, expected_value, "Error detail '{}' mismatch", detail_key);
+}
+
+
+// Additional convenience helpers for common patterns
+
+pub fn assert_error_message_contains(error: &Value, substring: &str) {
+  let message = error["message"].as_str().expect("error should have message");
+  assert!(message.contains(substring), "Expected message to contain '{}', got '{}'", substring, message);
+}
+
+pub fn assert_error_cause_json(error: &Value, expected_cause: &Value) {
+  let cause = &error["details"]["cause"];
+  assert!(cause.is_object(), "cause should be JSON object");
+  assert_eq!(cause, expected_cause, "cause mismatch");
+}
+
+pub fn assert_error_context(error: &Value, expected_context: &Value) {
+  assert_eq!(&error["details"]["context"], expected_context, "context mismatch");
+}
+
+
+pub fn jsonb(val: Value) -> JsonB {
+  JsonB(val)
+}

src/schemas.rs

@@ -0,0 +1,878 @@
+use crate::*;
+use serde_json::{json, Value};
+use pgrx::JsonB;
+
+// Helper to convert Value to JsonB
+fn jsonb(val: Value) -> JsonB {
+  JsonB(val)
+}
+
+pub fn simple_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "simple", 
+    "public": false,
+    "schemas": [{
+      "$id": "simple.request",
+      "type": "object",
+      "properties": {
+        "name": { "type": "string" },
+        "age": { "type": "integer", "minimum": 0 }
+      },
+      "required": ["name", "age"]
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn invalid_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "invalid_punc",
+    "public": false,
+    "schemas": [{
+      "$id": "invalid_punc.request",
+      "type": ["invalid_type_value"] 
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn errors_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "detailed_errors_test",
+    "public": false,
+    "schemas": [{
+      "$id": "detailed_errors_test.request",
+      "type": "object",
+      "properties": {
+        "address": {
+          "type": "object",
+          "properties": {
+            "street": { "type": "string" },
+            "city": { "type": "string", "maxLength": 10 }
+          },
+          "required": ["street", "city"]
+        }
+      },
+      "required": ["address"]
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn oneof_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "oneof_test",
+    "public": false,
+    "schemas": [{
+      "$id": "oneof_test.request",
+      "oneOf": [
+        {
+          "type": "object",
+          "properties": {
+            "string_prop": { "type": "string", "maxLength": 5 }
+          },
+          "required": ["string_prop"]
+        },
+        {
+          "type": "object", 
+          "properties": {
+            "number_prop": { "type": "number", "minimum": 10 }
+          },
+          "required": ["number_prop"]
+        }
+      ]
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn root_types_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([
+    {
+      "name": "object_test", 
+      "public": false,
+      "schemas": [{
+        "$id": "object_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" },
+          "age": { "type": "integer", "minimum": 0 }
+        },
+        "required": ["name", "age"]
+      }]
+    },
+    {
+      "name": "array_test",
+      "public": false,
+      "schemas": [{
+        "$id": "array_test.request",
+        "type": "array",
+        "items": {
+          "type": "object",
+          "properties": {
+            "id": { "type": "string", "format": "uuid" }
+          }
+        }
+      }]
+    }
+  ]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn strict_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([
+    {
+      "name": "basic_strict_test",
+      "public": true,
+      "schemas": [{
+        "$id": "basic_strict_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" }
+        }
+      }]
+    },
+    {
+      "name": "non_strict_test", 
+      "public": false,
+      "schemas": [{
+        "$id": "non_strict_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" }
+        }
+      }]
+    },
+    {
+      "name": "nested_strict_test",
+      "public": true,
+      "schemas": [{
+        "$id": "nested_strict_test.request",
+        "type": "object",
+        "properties": {
+          "user": {
+            "type": "object",
+            "properties": {
+              "name": { "type": "string" }
+            }
+          },
+          "items": {
+            "type": "array",
+            "items": {
+              "type": "object",
+              "properties": {
+                "id": { "type": "string" }
+              }
+            }
+          }
+        }
+      }]
+    },
+    {
+      "name": "already_unevaluated_test",
+      "public": true,
+      "schemas": [{
+        "$id": "already_unevaluated_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" }
+        },
+        "unevaluatedProperties": true
+      }]
+    },
+    {
+      "name": "already_additional_test",
+      "public": true,
+      "schemas": [{
+        "$id": "already_additional_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" }
+        },
+        "additionalProperties": false
+      }]
+    },
+    {
+      "name": "conditional_strict_test",
+      "public": true,
+      "schemas": [{
+        "$id": "conditional_strict_test.request",
+        "type": "object",
+        "properties": {
+          "creating": { "type": "boolean" }
+        },
+        "if": {
+          "properties": {
+            "creating": { "const": true }
+          }
+        },
+        "then": {
+          "properties": {
+            "name": { "type": "string" }
+          },
+          "required": ["name"]
+        }
+      }]
+    }
+  ]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn required_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "basic_validation_test", 
+    "public": false,
+    "schemas": [{
+      "$id": "basic_validation_test.request",
+      "type": "object",
+      "properties": {
+        "name": { "type": "string" },
+        "age": { "type": "integer", "minimum": 0 }
+      },
+      "required": ["name", "age"]
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn dependencies_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "dependency_split_test",
+    "public": false,
+    "schemas": [{
+      "$id": "dependency_split_test.request",
+      "type": "object",
+      "properties": {
+        "creating": { "type": "boolean" },
+        "name": { "type": "string" },
+        "kind": { "type": "string" },
+        "description": { "type": "string" }
+      },
+      "dependencies": {
+        "creating": ["name", "kind"]
+      }
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn nested_req_deps_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "nested_dep_test", 
+    "public": false,
+    "schemas": [{
+      "$id": "nested_dep_test.request",
+      "type": "object",
+      "properties": {
+        "items": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "properties": {
+              "id": { "type": "string" },
+              "creating": { "type": "boolean" },
+              "name": { "type": "string" },
+              "kind": { "type": "string" }
+            },
+            "required": ["id"],
+            "dependencies": {
+              "creating": ["name", "kind"]
+            }
+          }
+        }
+      },
+      "required": ["items"]
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn additional_properties_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([
+    {
+      "name": "additional_props_test",
+      "public": false,
+      "schemas": [{
+        "$id": "additional_props_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" },
+          "age": { "type": "number" }
+        },
+        "additionalProperties": false
+      }]
+    },
+    {
+      "name": "nested_additional_props_test",
+      "public": false,
+      "schemas": [{
+        "$id": "nested_additional_props_test.request",
+        "type": "object", 
+        "properties": {
+          "user": {
+            "type": "object",
+            "properties": {
+              "name": { "type": "string" }
+            },
+            "additionalProperties": false
+          }
+        }
+      }]
+    }
+  ]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn unevaluated_properties_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([
+    {
+      "name": "simple_unevaluated_test",
+      "public": false,
+      "schemas": [{
+        "$id": "simple_unevaluated_test.request",
+        "type": "object",
+        "properties": {
+          "name": { "type": "string" },
+          "age": { "type": "number" }
+        },
+        "patternProperties": {
+          "^attr_": { "type": "string" }
+        },
+        "unevaluatedProperties": false
+      }]
+    },
+    {
+      "name": "conditional_unevaluated_test",
+      "public": false,
+      "schemas": [{
+        "$id": "conditional_unevaluated_test.request",
+        "type": "object",
+        "allOf": [
+          {
+            "properties": {
+              "firstName": { "type": "string" }
+            }
+          },
+          {
+            "properties": {
+              "lastName": { "type": "string" }
+            }
+          }
+        ],
+        "properties": {
+          "age": { "type": "number" }
+        },
+        "unevaluatedProperties": false
+      }]
+    }
+  ]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn format_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([]);
+  let puncs = json!([{
+    "name": "format_test",
+    "public": false,
+    "schemas": [{
+      "$id": "format_test.request",
+      "type": "object",
+      "properties": {
+        "uuid": { "type": "string", "format": "uuid" },
+        "date_time": { "type": "string", "format": "date-time" },
+        "email": { "type": "string", "format": "email" }
+      }
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn property_merging_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([
+    {
+      "name": "entity",
+      "schemas": [{
+        "$id": "entity",
+        "type": "object",
+        "properties": {
+          "id": { "type": "string" },
+          "name": { "type": "string" },
+          "type": { "type": "string" }
+        },
+        "required": ["id"]
+      }]
+    },
+    {
+      "name": "user",
+      "schemas": [{
+        "$id": "user",
+        "$ref": "entity",
+        "properties": {
+          "password": { "type": "string", "minLength": 8 }
+        },
+        "required": ["password"]
+      }]
+    },
+    {
+      "name": "person", 
+      "schemas": [{
+        "$id": "person",
+        "$ref": "user",
+        "properties": {
+          "first_name": { "type": "string", "minLength": 1 },
+          "last_name": { "type": "string", "minLength": 1 }
+        },
+        "required": ["first_name", "last_name"]
+      }]
+    }
+  ]);
+
+  let puncs = json!([]);
+  
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn required_merging_schemas() -> JsonB {
+  let enums = json!([]);
+  
+  let types = json!([
+    {
+      "name": "entity",
+      "schemas": [{
+        "$id": "entity",
+        "type": "object",
+        "properties": {
+          "id": { "type": "string", "format": "uuid" },
+          "type": { "type": "string" },
+          "created_by": { "type": "string", "format": "uuid" }
+        },
+        "required": ["id", "type", "created_by"]
+      }]
+    },
+    {
+      "name": "user",
+      "schemas": [{
+        "$id": "user",
+        "$ref": "entity",
+        "properties": {
+          "password": { "type": "string", "minLength": 8 }
+        },
+        "if": {
+          "properties": { "type": { "const": "user" } }
+        },
+        "then": {
+          "required": ["password"]
+        }
+      }]
+    },
+    {
+      "name": "person",
+      "schemas": [{
+        "$id": "person", 
+        "$ref": "user",
+        "properties": {
+          "first_name": { "type": "string", "minLength": 1 },
+          "last_name": { "type": "string", "minLength": 1 }
+        },
+        "if": {
+          "properties": { "type": { "const": "person" } }
+        },
+        "then": {
+          "required": ["first_name", "last_name"]
+        }
+      }]
+    }
+  ]);
+
+  let puncs = json!([]);
+  
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn dependencies_merging_schemas() -> JsonB {
+  let enums = json!([]);
+  
+  let types = json!([
+    {
+      "name": "entity",
+      "schemas": [{
+        "$id": "entity",
+        "type": "object",
+        "properties": {
+          "id": { "type": "string", "format": "uuid" },
+          "type": { "type": "string" },
+          "created_by": { "type": "string", "format": "uuid" },
+          "creating": { "type": "boolean" },
+          "name": { "type": "string" }
+        },
+        "required": ["id", "type", "created_by"],
+        "dependencies": {
+          "creating": ["name"]
+        }
+      }]
+    },
+    {
+      "name": "user",
+      "schemas": [{
+        "$id": "user",
+        "$ref": "entity",
+        "properties": {
+          "password": { "type": "string", "minLength": 8 }
+        },
+        "dependencies": {
+          "creating": ["name"]
+        }
+      }]
+    },
+    {
+      "name": "person",
+      "schemas": [{
+        "$id": "person",
+        "$ref": "user", 
+        "properties": {
+          "first_name": { "type": "string", "minLength": 1 },
+          "last_name": { "type": "string", "minLength": 1 }
+        },
+        "dependencies": {
+          "creating": ["first_name", "last_name"]
+        }
+      }]
+    }
+  ]);
+
+  let puncs = json!([]);
+  
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn punc_with_refs_schemas() -> JsonB {
+  let enums = json!([]);
+
+  let types = json!([
+    {
+      "name": "entity",
+      "schemas": [{
+        "$id": "entity",
+        "type": "object",
+        "properties": {
+          "id": { "type": "string" },
+          "name": { "type": "string" },
+          "type": { "type": "string" }
+        },
+        "required": ["id", "type"]
+      }]
+    },
+    {
+      "name": "person",
+      "schemas": [{
+        "$id": "person",
+        "$ref": "entity",
+        "properties": {
+          "first_name": { "type": "string", "minLength": 1 },
+          "last_name": { "type": "string", "minLength": 1 },
+          "address": {
+            "type": "object",
+            "properties": {
+              "street": { "type": "string" },
+              "city": { "type": "string" }
+            },
+            "required": ["street", "city"]
+          }
+        }
+      }]
+    }
+  ]);
+
+  let puncs = json!([
+    {
+      "name": "public_ref_test",
+      "public": true,
+      "schemas": [{
+        "$id": "public_ref_test.request",
+        "$ref": "person"
+      }]
+    },
+    {
+      "name": "private_ref_test",
+      "public": false,
+      "schemas": [{
+        "$id": "private_ref_test.request",
+        "$ref": "person"
+      }]
+    }
+  ]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn enum_schemas() -> JsonB {
+  let enums = json!([
+    {
+      "name": "task_priority",
+      "values": ["low", "medium", "high", "urgent"],
+      "schemas": [{
+        "$id": "task_priority",
+        "type": "string",
+        "enum": ["low", "medium", "high", "urgent"]
+      }]
+    }
+  ]);
+
+  let types = json!([]);
+
+  let puncs = json!([{
+    "name": "enum_ref_test",
+    "public": false,
+    "schemas": [{
+      "$id": "enum_ref_test.request",
+      "type": "object",
+      "properties": {
+        "priority": { "$ref": "task_priority" }
+      },
+      "required": ["priority"]
+    }]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn punc_local_refs_schemas() -> JsonB {
+  let enums = json!([]);
+
+  let types = json!([
+    {
+      "name": "global_thing",
+      "schemas": [{
+        "$id": "global_thing",
+        "type": "object",
+        "properties": {
+          "id": { "type": "string", "format": "uuid" },
+          "type": { "type": "string" }
+        },
+        "required": ["id", "type"]
+      }]
+    }
+  ]);
+
+  let puncs = json!([
+    {
+      "name": "punc_with_local_ref_test",
+      "public": false,
+      "schemas": [
+        {
+          "$id": "local_address",
+          "type": "object",
+          "properties": {
+            "street": { "type": "string" },
+            "city": { "type": "string" }
+          },
+          "required": ["street", "city"]
+        },
+        {
+          "$id": "punc_with_local_ref_test.request",
+          "$ref": "local_address"
+        }
+      ]
+    },
+    {
+      "name": "punc_with_local_ref_to_global_test",
+      "public": false,
+      "schemas": [
+        {
+          "$id": "local_user_with_thing",
+          "type": "object",
+          "properties": {
+            "user_name": { "type": "string" },
+            "thing": { "$ref": "global_thing" }
+          },
+          "required": ["user_name", "thing"]
+        },
+        {
+          "$id": "punc_with_local_ref_to_global_test.request",
+          "$ref": "local_user_with_thing"
+        }
+      ]
+    }
+  ]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn title_override_schemas() -> JsonB {
+  let enums = json!([]);
+
+  let types = json!([
+    {
+      "name": "base_with_title",
+      "schemas": [{
+        "$id": "base_with_title",
+        "type": "object",
+        "title": "Base Title",
+        "properties": {
+          "name": { "type": "string" },
+          "type": { "type": "string" }
+        },
+        "required": ["name"]
+      }]
+    },
+    {
+      "name": "override_with_title",
+      "schemas": [{
+        "$id": "override_with_title",
+        "$ref": "base_with_title",
+        "title": "Override Title"
+      }]
+    }
+  ]);
+
+  let puncs = json!([]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn format_with_ref_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([
+    {
+      "name": "entity",
+      "schemas": [{
+        "$id": "entity",
+        "type": "object",
+        "properties": {
+          "id": { "type": "string", "format": "uuid" },
+          "type": { "type": "string" },
+          "name": { "type": "string" }
+        },
+        "required": ["id", "type"]
+      }]
+    },
+    {
+      "name": "job",
+      "schemas": [{
+        "$id": "job",
+        "$ref": "entity",
+        "properties": {
+          "worker_id": { "type": "string", "format": "uuid" }
+        }
+      }]
+    }
+  ]);
+
+  let puncs = json!([{
+    "name": "save_job",
+    "public": true,
+    "schemas": [
+      {
+        "$id": "save_job.request",
+        "$ref": "job"
+      },
+      {
+        "$id": "save_job.response",
+        "$ref": "job"
+      }
+    ]
+  }]);
+
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}
+
+pub fn type_matching_schemas() -> JsonB {
+  let enums = json!([]);
+  let types = json!([
+    {
+      "name": "entity",
+      "schemas": [{
+        "$id": "entity",
+        "type": "object",
+        "properties": { "type": { "type": "string" }, "name": { "type": "string" } },
+        "required": ["type", "name"]
+      }]
+    },
+    {
+      "name": "job",
+      "schemas": [{
+        "$id": "job",
+        "$ref": "entity",
+        "properties": { "job_id": { "type": "string" } },
+        "required": ["job_id"]
+      }]
+    },
+    {
+      "name": "super_job",
+      "schemas": [
+        {
+          "$id": "super_job",
+          "$ref": "job",
+          "properties": { "manager_id": { "type": "string" } },
+          "required": ["manager_id"]
+        },
+        {
+          "$id": "super_job.short",
+          "$ref": "super_job",
+          "properties": { "name": { "maxLength": 10 } }
+        }
+      ]
+    }
+  ]);
+  let puncs = json!([{
+    "name": "type_test_punc",
+    "public": false,
+    "schemas": [{
+      "$id": "type_test_punc.request",
+      "type": "object",
+      "properties": {
+        "root_job": { "$ref": "job" },
+        "nested_or_super_job": {
+          "oneOf": [
+            { "$ref": "super_job" },
+            {
+              "type": "object",
+              "properties": {
+                "my_job": { "$ref": "job" }
+              },
+              "required": ["my_job"]
+            }
+          ]
+        }
+      },
+      "required": ["root_job", "nested_or_super_job"]
+    }]
+  }]);
+  cache_json_schemas(jsonb(enums), jsonb(types), jsonb(puncs))
+}

validator/CHANGELOG.md

@@ -0,0 +1,81 @@
+# Changelog
+
+## [Unreleased]
+
+### Bug Fixes
+- validator: ensure `uneval` state is propagated when `$ref` validation fails
+
+## [0.6.1] - 2025-01-07
+
+### Bug Fixes
+- fix: FileLoader should not be used in wasm
+
+## [0.6.0] - 2024-05-30
+
+### Braking Changes
+- loader: Allow to replace entirely
+
+### Bug Fixes
+- seperate doc loading from root creation
+- validator: if contentEncoding fails, skip contentMediaType
+- loader: should load latest from metaschemas dir
+- fix: hash for json numbers with zero fractions
+- fix: resources/anchors in non-std schema loc not supported
+
+### Changes
+- boon binary artificats under github release
+- boon binary `--cacert` option
+- boon binary `--insecure` flag
+
+## [0.5.3] - 2024-01-27
+
+### Changes
+- updated dependencies
+
+## [0.5.2] - 2024-01-27
+
+### Bug Fixes
+
+- Error message for failed const validation is wrong
+
+## [0.5.1] - 2023-07-13
+
+### Changes
+
+- WASM compatibility
+- minor performance improvements
+
+## [0.5.0] - 2023-03-29
+
+### Breaking Changes
+- chages to error api
+
+### Performance
+- minor improvements in validation
+
+## [0.4.0] - 2023-03-24
+
+### Breaking Changes
+- chages to error api
+
+### Fixed
+- Compler.add_resource should not check file exists
+
+### Added
+- implement `contentSchema` keyword
+- ECMA-262 regex compatibility
+- add example_custom_content_encoding
+- add example_custom_content_media_type
+
+### Performance
+- significant improvement in validation
+
+## [0.3.1] - 2023-03-07
+
+### Added
+- add example_from_yaml_files
+- cli: support yaml files
+
+### Fixed
+- ensure fragment decoded before use
+- $dynamicRef w/o anchor is same as $ref

validator/Cargo.toml

@@ -0,0 +1,39 @@
+[package]
+name = "boon"
+version = "0.6.1"
+edition = "2021"
+description = "JSONSchema (draft 2020-12, draft 2019-09, draft-7, draft-6, draft-4) Validation"
+readme = "README.md"
+repository = "https://github.com/santhosh-tekuri/boon"
+authors = ["santhosh kumar tekuri <santhosh.tekuri@gmail.com>"]
+keywords = ["jsonschema", "validation"]
+license = "MIT OR Apache-2.0"
+categories = ["web-programming"]
+exclude = [ "tests", ".github", ".gitmodules" ]
+
+[dependencies]
+pgrx = "0.15.0"
+serde = "1"
+serde_json = "1"
+regex = "1.10.3"
+regex-syntax = "0.8.2"
+url = "2"
+fluent-uri = "0.3.2"
+idna = "1.0"
+percent-encoding = "2"
+once_cell = "1"
+base64 = "0.22"
+ahash = "0.8.3"
+appendlist = "1.4"
+
+[dev-dependencies]
+pgrx-tests = "0.15.0"
+serde = { version = "1.0", features = ["derive"] }
+serde_yaml = "0.9"
+ureq = "2.12"
+rustls = "0.23"
+criterion = "0.5"
+
+[[bench]]
+name = "bench"
+harness = false

validator/LICENSE-APACHE

@@ -0,0 +1,177 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
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+
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+      of this License, Derivative Works shall not include works that remain
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+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
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+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
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+      designated in writing by the copyright owner as "Not a Contribution."
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+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
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+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS

validator/LICENSE-MIT

@@ -0,0 +1,18 @@
+Copyright 2023 Santhosh Kumar Tekuri
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the “Software”), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

validator/README.md

@@ -0,0 +1,88 @@
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
+[![Crates.io](https://img.shields.io/crates/v/boon.svg)](https://crates.io/crates/boon)
+[![docs.rs](https://docs.rs/boon/badge.svg)](https://docs.rs/boon/)
+[![Build Status](https://github.com/santhosh-tekuri/boon/actions/workflows/rust.yml/badge.svg?branch=main)](https://github.com/santhosh-tekuri/boon/actions/workflows/rust.yml)
+[![codecov](https://codecov.io/gh/santhosh-tekuri/boon/branch/main/graph/badge.svg?token=A2YC4A0BLG)](https://codecov.io/gh/santhosh-tekuri/boon)
+[![dependency status](https://deps.rs/repo/github/Santhosh-tekuri/boon/status.svg?refresh)](https://deps.rs/repo/github/Santhosh-tekuri/boon)
+
+[Examples](https://github.com/santhosh-tekuri/boon/blob/main/tests/examples.rs)
+[Changelog](https://github.com/santhosh-tekuri/boon/blob/main/CHANGELOG.md)
+
+## Library Features
+
+- [x] pass [JSON-Schema-Test-Suite](https://github.com/json-schema-org/JSON-Schema-Test-Suite) excluding optional(compare with other impls at [bowtie](https://bowtie-json-schema.github.io/bowtie/#))
+  - [x] [![draft-04](https://img.shields.io/endpoint?url=https://bowtie.report/badges/rust-boon/compliance/draft4.json)](https://bowtie.report/#/dialects/draft4)
+  - [x] [![draft-06](https://img.shields.io/endpoint?url=https://bowtie.report/badges/rust-boon/compliance/draft6.json)](https://bowtie.report/#/dialects/draft6)
+  - [x] [![draft-07](https://img.shields.io/endpoint?url=https://bowtie.report/badges/rust-boon/compliance/draft7.json)](https://bowtie.report/#/dialects/draft7)
+  - [x] [![draft/2019-09](https://img.shields.io/endpoint?url=https://bowtie.report/badges/rust-boon/compliance/draft2019-09.json)](https://bowtie.report/#/dialects/draft2019-09)
+  - [x] [![draft/2020-12](https://img.shields.io/endpoint?url=https://bowtie.report/badges/rust-boon/compliance/draft2020-12.json)](https://bowtie.report/#/dialects/draft2020-12)
+- [x] detect infinite loop traps
+  - [x] `$schema` cycle
+  - [x] validation cycle
+- [x] custom `$schema` url
+- [x] vocabulary based validation
+- [x] ECMA-262 regex compatibility (pass tests from `optional/ecmascript-regex.json`)
+- [x] format assertions
+  - [x] flag to enable in draft >= 2019-09
+  - [x] custom format registration
+  - [x] built-in formats
+    - [x] regex, uuid
+    - [x] ipv4, ipv6
+    - [x] hostname, email
+    - [x] idn-hostname, idn-email
+    - [x] date, time, date-time, duration
+    - [x] json-pointer, relative-json-pointer
+    - [x] uri, uri-reference, uri-template
+    - [x] iri, iri-reference
+    - [x] period
+- [x] content assertions
+  - [x] flag to enable in draft >= 7
+  - [x] contentEncoding
+    - [x] base64
+    - [x] custom
+  - [x] contentMediaType
+    - [x] application/json
+    - [x] custom
+  - [x] contentSchema
+- [x] errors
+  - [x] introspectable
+  - [x] hierarchy
+    - [x] alternative display with `#`
+  - [x] output
+    - [x] flag
+    - [x] basic
+    - [x] detailed
+- [ ] custom vocabulary
+
+## CLI
+
+to install: `cargo install boon-cli --locked`
+
+or download it from [releases](https://github.com/santhosh-tekuri/boon/releases)
+
+```
+Usage: boon [OPTIONS] SCHEMA [INSTANCE...]
+
+Options:
+    -h, --help          Print help information
+    -q, --quiet         Do not print errors
+    -d, --draft <VER>   Draft used when '$schema' is missing. Valid values 4,
+                        6, 7, 2019, 2020 (default 2020)
+    -o, --output <FMT>  Output format. Valid values simple, alt, flag, basic,
+                        detailed (default simple)
+    -f, --assert-format
+                        Enable format assertions with draft >= 2019
+    -c, --assert-content
+                        Enable content assertions with draft >= 7
+        --cacert <FILE> Use the specified PEM certificate file to verify the
+                        peer. The file may contain multiple CA certificates
+    -k, --insecure      Use insecure TLS connection
+```
+
+This cli can validate both schema and multiple instances.
+
+It support both json and yaml files
+
+exit code is: 
+- `1` if command line arguments are invalid.
+- `2` if there are errors

validator/benches/bench.rs

@@ -0,0 +1,26 @@
+use std::{env, fs::File};
+
+use boon::{Compiler, Schemas};
+use criterion::{criterion_group, criterion_main, Criterion};
+use serde_json::Value;
+
+pub fn validate(c: &mut Criterion) {
+    let (Ok(schema), Ok(instance)) = (env::var("SCHEMA"), env::var("INSTANCE")) else {
+        panic!("SCHEMA, INSTANCE environment variables not set");
+    };
+
+    let mut schemas = Schemas::new();
+    let mut compiler = Compiler::new();
+    compiler.enable_format_assertions();
+    let sch = compiler.compile(&schema, &mut schemas).unwrap();
+    let rdr = File::open(&instance).unwrap();
+    let inst: Value = if instance.ends_with(".yaml") || instance.ends_with(".yml") {
+        serde_yaml::from_reader(rdr).unwrap()
+    } else {
+        serde_json::from_reader(rdr).unwrap()
+    };
+    c.bench_function("boon", |b| b.iter(|| schemas.validate(&inst, sch).unwrap()));
+}
+
+criterion_group!(benches, validate);
+criterion_main!(benches);

validator/cli/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "boon-cli"
+version = "0.6.2"
+edition = "2021"
+description = "cli for JSONSchema (draft 2020-12, draft 2019-09, draft-7, draft-6, draft-4) Validation"
+repository = "https://github.com/santhosh-tekuri/boon/cli"
+authors = ["santhosh kumar tekuri <santhosh.tekuri@gmail.com>"]
+keywords = ["jsonschema", "validation"]
+categories = ["web-programming"]
+license = "MIT OR Apache-2.0"
+
+[dependencies]
+boon = { version = "0.6.1", path = ".."}
+url = "2"
+getopts = "0.2"
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1"
+serde_yaml = "0.9"
+ureq = "2.12"
+rustls = { version = "0.23", features = ["ring"] }
+rustls-pemfile = "2.1"
+
+[[bin]]
+name = "boon"
+path = "src/main.rs"

validator/cli/src/main.rs

@@ -0,0 +1,316 @@
+use core::panic;
+use std::{env, error::Error, fs::File, io::BufReader, process, str::FromStr, sync::Arc};
+
+use boon::{Compiler, Draft, Schemas, SchemeUrlLoader, UrlLoader};
+use getopts::Options;
+use rustls::client::danger::{HandshakeSignatureValid, ServerCertVerified, ServerCertVerifier};
+use serde_json::Value;
+use ureq::Agent;
+use url::Url;
+
+fn main() {
+    let opts = options();
+    let matches = match opts.parse(env::args().skip(1)) {
+        Ok(m) => m,
+        Err(f) => {
+            eprintln!("{f}");
+            eprintln!();
+            eprintln!("{}", opts.usage(BRIEF));
+            process::exit(1)
+        }
+    };
+
+    if matches.opt_present("version") {
+        println!("{}", env!("CARGO_PKG_VERSION"));
+        process::exit(0);
+    }
+
+    if matches.opt_present("help") {
+        println!("{}", opts.usage(BRIEF));
+        process::exit(0);
+    }
+
+    // draft --
+    let mut draft = Draft::default();
+    if let Some(v) = matches.opt_str("draft") {
+        let Ok(v) = usize::from_str(&v) else {
+            eprintln!("invalid draft: {v}");
+            eprintln!();
+            eprintln!("{}", opts.usage(BRIEF));
+            process::exit(1);
+        };
+        draft = match v {
+            4 => Draft::V4,
+            6 => Draft::V6,
+            7 => Draft::V7,
+            2019 => Draft::V2019_09,
+            2020 => Draft::V2020_12,
+            _ => {
+                eprintln!("invalid draft: {v}");
+                eprintln!();
+                eprintln!("{}", opts.usage(BRIEF));
+                process::exit(1);
+            }
+        };
+    }
+
+    // output --
+    let output = matches.opt_str("output");
+    if let Some(o) = &output {
+        if !matches!(o.as_str(), "simple" | "alt" | "flag" | "basic" | "detailed") {
+            eprintln!("invalid output: {o}");
+            eprintln!();
+            eprintln!("{}", opts.usage(BRIEF));
+            process::exit(1);
+        }
+    }
+
+    // flags --
+    let quiet = matches.opt_present("quiet");
+    let assert_format = matches.opt_present("assert-format");
+    let assert_content = matches.opt_present("assert-content");
+    let insecure = matches.opt_present("insecure");
+
+    // schema --
+    let Some(schema) = matches.free.first() else {
+        eprintln!("missing SCHEMA");
+        eprintln!();
+        eprintln!("{}", opts.usage(BRIEF));
+        process::exit(1);
+    };
+
+    // compile --
+    let mut schemas = Schemas::new();
+    let mut compiler = Compiler::new();
+    let mut loader = SchemeUrlLoader::new();
+    loader.register("file", Box::new(FileUrlLoader));
+    let cacert = matches.opt_str("cacert");
+    let cacert = cacert.as_deref();
+    loader.register("http", Box::new(HttpUrlLoader::new(cacert, insecure)));
+    loader.register("https", Box::new(HttpUrlLoader::new(cacert, insecure)));
+    compiler.use_loader(Box::new(loader));
+    compiler.set_default_draft(draft);
+    if assert_format {
+        compiler.enable_format_assertions();
+    }
+    if assert_content {
+        compiler.enable_content_assertions();
+    }
+    let sch = match compiler.compile(schema, &mut schemas) {
+        Ok(sch) => {
+            println!("schema {schema}: ok");
+            sch
+        }
+        Err(e) => {
+            println!("schema {schema}: failed");
+            if !quiet {
+                println!("{e:#}");
+            }
+            process::exit(2);
+        }
+    };
+
+    // validate --
+    let mut all_valid = true;
+    for instance in &matches.free[1..] {
+        if !quiet {
+            println!();
+        }
+        let rdr = match File::open(instance) {
+            Ok(rdr) => BufReader::new(rdr),
+            Err(e) => {
+                println!("instance {instance}: failed");
+                if !quiet {
+                    println!("error reading file {instance}: {e}");
+                }
+                all_valid = false;
+                continue;
+            }
+        };
+        let value: Result<Value, String> =
+            if instance.ends_with(".yaml") || instance.ends_with(".yml") {
+                serde_yaml::from_reader(rdr).map_err(|e| e.to_string())
+            } else {
+                serde_json::from_reader(rdr).map_err(|e| e.to_string())
+            };
+        let value = match value {
+            Ok(v) => v,
+            Err(e) => {
+                println!("instance {instance}: failed");
+                if !quiet {
+                    println!("error parsing file {instance}: {e}");
+                }
+                all_valid = false;
+                continue;
+            }
+        };
+        match schemas.validate(&value, sch) {
+            Ok(_) => println!("instance {instance}: ok"),
+            Err(e) => {
+                println!("instance {instance}: failed");
+                if !quiet {
+                    match &output {
+                        Some(out) => match out.as_str() {
+                            "simple" => println!("{e}"),
+                            "alt" => println!("{e:#}"),
+                            "flag" => println!("{:#}", e.flag_output()),
+                            "basic" => println!("{:#}", e.basic_output()),
+                            "detailed" => println!("{:#}", e.detailed_output()),
+                            _ => (),
+                        },
+                        None => println!("{e}"),
+                    }
+                }
+                all_valid = false;
+                continue;
+            }
+        };
+    }
+    if !all_valid {
+        process::exit(2);
+    }
+}
+
+const BRIEF: &str = "Usage: boon [OPTIONS] SCHEMA [INSTANCE...]";
+
+fn options() -> Options {
+    let mut opts = Options::new();
+    opts.optflag("v", "version", "Print version and exit");
+    opts.optflag("h", "help", "Print help information");
+    opts.optflag("q", "quiet", "Do not print errors");
+    opts.optopt(
+        "d",
+        "draft",
+        "Draft used when '$schema' is missing. Valid values 4, 6, 7, 2019, 2020 (default 2020)",
+        "<VER>",
+    );
+    opts.optopt(
+        "o",
+        "output",
+        "Output format. Valid values simple, alt, flag, basic, detailed (default simple)",
+        "<FMT>",
+    );
+    opts.optflag(
+        "f",
+        "assert-format",
+        "Enable format assertions with draft >= 2019",
+    );
+    opts.optflag(
+        "c",
+        "assert-content",
+        "Enable content assertions with draft >= 7",
+    );
+    opts.optopt(
+        "",
+        "cacert",
+        "Use the specified PEM certificate file to verify the peer. The file may contain multiple CA certificates",
+        "<FILE>",
+    );
+    opts.optflag("k", "insecure", "Use insecure TLS connection");
+    opts
+}
+
+struct FileUrlLoader;
+impl UrlLoader for FileUrlLoader {
+    fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+        let url = Url::parse(url)?;
+        let path = url.to_file_path().map_err(|_| "invalid file path")?;
+        let file = File::open(&path)?;
+        if path
+            .extension()
+            .filter(|&ext| ext == "yaml" || ext == "yml")
+            .is_some()
+        {
+            Ok(serde_yaml::from_reader(file)?)
+        } else {
+            Ok(serde_json::from_reader(file)?)
+        }
+    }
+}
+
+struct HttpUrlLoader(Agent);
+
+impl HttpUrlLoader {
+    fn new(cacert: Option<&str>, insecure: bool) -> Self {
+        let mut builder = ureq::builder();
+        if let Some(cacert) = cacert {
+            let file = File::open(cacert).unwrap_or_else(|e| panic!("error opening {cacert}: {e}"));
+            let certs: Result<Vec<_>, _> =
+                rustls_pemfile::certs(&mut BufReader::new(file)).collect();
+            let certs = certs.unwrap_or_else(|e| panic!("error reading cacert: {e}"));
+            assert!(!certs.is_empty(), "no certs in cacert");
+            let mut store = rustls::RootCertStore::empty();
+            for cert in certs {
+                store
+                    .add(cert)
+                    .unwrap_or_else(|e| panic!("error adding cert: {e}"))
+            }
+            let tls_config = rustls::ClientConfig::builder()
+                .with_root_certificates(store)
+                .with_no_client_auth();
+            builder = builder.tls_config(tls_config.into());
+        } else if insecure {
+            let tls_config = rustls::ClientConfig::builder()
+                .dangerous()
+                .with_custom_certificate_verifier(Arc::new(InsecureVerifier))
+                .with_no_client_auth();
+            builder = builder.tls_config(tls_config.into());
+        }
+        Self(builder.build())
+    }
+}
+
+impl UrlLoader for HttpUrlLoader {
+    fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+        let response = self.0.get(url).call()?;
+        let is_yaml = url.ends_with(".yaml") || url.ends_with(".yml") || {
+            let ctype = response.content_type();
+            ctype.ends_with("/yaml") || ctype.ends_with("-yaml")
+        };
+        if is_yaml {
+            Ok(serde_yaml::from_reader(response.into_reader())?)
+        } else {
+            Ok(serde_json::from_reader(response.into_reader())?)
+        }
+    }
+}
+
+#[derive(Debug)]
+struct InsecureVerifier;
+
+impl ServerCertVerifier for InsecureVerifier {
+    fn verify_server_cert(
+        &self,
+        _end_entity: &rustls::pki_types::CertificateDer<'_>,
+        _intermediates: &[rustls::pki_types::CertificateDer<'_>],
+        _server_name: &rustls::pki_types::ServerName<'_>,
+        _ocsp_response: &[u8],
+        _now: rustls::pki_types::UnixTime,
+    ) -> Result<rustls::client::danger::ServerCertVerified, rustls::Error> {
+        Ok(ServerCertVerified::assertion())
+    }
+
+    fn verify_tls12_signature(
+        &self,
+        _message: &[u8],
+        _cert: &rustls::pki_types::CertificateDer<'_>,
+        _dss: &rustls::DigitallySignedStruct,
+    ) -> Result<rustls::client::danger::HandshakeSignatureValid, rustls::Error> {
+        Ok(HandshakeSignatureValid::assertion())
+    }
+
+    fn verify_tls13_signature(
+        &self,
+        _message: &[u8],
+        _cert: &rustls::pki_types::CertificateDer<'_>,
+        _dss: &rustls::DigitallySignedStruct,
+    ) -> Result<rustls::client::danger::HandshakeSignatureValid, rustls::Error> {
+        Ok(HandshakeSignatureValid::assertion())
+    }
+
+    fn supported_verify_schemes(&self) -> Vec<rustls::SignatureScheme> {
+        rustls::crypto::ring::default_provider()
+            .signature_verification_algorithms
+            .supported_schemes()
+    }
+}

validator/src/compiler.rs

@@ -0,0 +1,985 @@
+use std::{cmp::Ordering, collections::HashMap, error::Error, fmt::Display};
+
+use regex::Regex;
+use serde_json::{Map, Value};
+use url::Url;
+
+use crate::{content::*, draft::*, ecma, formats::*, root::*, roots::*, util::*, *};
+
+/// Supported draft versions
+#[non_exhaustive]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum Draft {
+  /// Draft for `http://json-schema.org/draft-04/schema`
+  V4,
+  /// Draft for `http://json-schema.org/draft-06/schema`
+  V6,
+  /// Draft for `http://json-schema.org/draft-07/schema`
+  V7,
+  /// Draft for `https://json-schema.org/draft/2019-09/schema`
+  V2019_09,
+  /// Draft for `https://json-schema.org/draft/2020-12/schema`
+  V2020_12,
+}
+
+impl Draft {
+  /**
+  Get [`Draft`] for given `url`
+
+  # Arguments
+
+  * `url` - accepts both `http` and `https` and ignores any fragments in url
+
+  # Examples
+
+  ```
+  # use boon::*;
+  assert_eq!(Draft::from_url("https://json-schema.org/draft/2020-12/schema"), Some(Draft::V2020_12));
+  assert_eq!(Draft::from_url("http://json-schema.org/draft-07/schema#"), Some(Draft::V7));
+  ```
+  */
+  pub fn from_url(url: &str) -> Option<Draft> {
+    match crate::draft::Draft::from_url(url) {
+      Some(draft) => match draft.version {
+        4 => Some(Draft::V4),
+        6 => Some(Draft::V6),
+        7 => Some(Draft::V7),
+        2019 => Some(Draft::V2019_09),
+        2020 => Some(Draft::V2020_12),
+        _ => None,
+      },
+      None => None,
+    }
+  }
+
+  pub(crate) fn internal(&self) -> &'static crate::draft::Draft {
+    match self {
+      Draft::V4 => &DRAFT4,
+      Draft::V6 => &DRAFT6,
+      Draft::V7 => &DRAFT7,
+      Draft::V2019_09 => &DRAFT2019,
+      Draft::V2020_12 => &DRAFT2020,
+    }
+  }
+}
+
+/// Returns latest draft supported
+impl Default for Draft {
+  fn default() -> Self {
+    Draft::V2020_12
+  }
+}
+
+/// JsonSchema compiler.
+#[derive(Default)]
+pub struct Compiler {
+  roots: Roots,
+  assert_format: bool,
+  assert_content: bool,
+  formats: HashMap<&'static str, Format>,
+  decoders: HashMap<&'static str, Decoder>,
+  media_types: HashMap<&'static str, MediaType>,
+}
+
+impl Compiler {
+  pub fn new() -> Self {
+    Self::default()
+  }
+
+  /**
+  Overrides the draft used to compile schemas without
+  explicit `$schema` field.
+
+  By default this library uses latest draft supported.
+
+  The use of this option is HIGHLY encouraged to ensure
+  continued correct operation of your schema. The current
+  default value will not stay the same over time.
+  */
+  pub fn set_default_draft(&mut self, d: Draft) {
+    self.roots.default_draft = d.internal()
+  }
+
+  /**
+  Always enable format assertions.
+
+  # Default Behavior
+
+  - for draft-07 and earlier: enabled
+  - for draft/2019-09: disabled, unless
+   metaschema says `format` vocabulary is required
+  - for draft/2020-12: disabled, unless
+   metaschema says `format-assertion` vocabulary is required
+  */
+  pub fn enable_format_assertions(&mut self) {
+    self.assert_format = true;
+  }
+
+  /**
+  Always enable content assertions.
+
+  content assertions include keywords:
+  - contentEncoding
+  - contentMediaType
+  - contentSchema
+
+  Default Behavior is always disabled.
+  */
+  pub fn enable_content_assertions(&mut self) {
+    self.assert_content = true;
+  }
+
+  /// Overrides default [`UrlLoader`] used to load schema resources
+  pub fn use_loader(&mut self, url_loader: Box<dyn UrlLoader>) {
+    self.roots.loader.use_loader(url_loader);
+  }
+
+  /**
+  Registers custom `format`
+
+  # Note
+
+  - `regex` format cannot be overridden
+  - format assertions are disabled for draft >= 2019-09.
+    see [`Compiler::enable_format_assertions`]
+  */
+  pub fn register_format(&mut self, format: Format) {
+    if format.name != "regex" {
+      self.formats.insert(format.name, format);
+    }
+  }
+
+  /**
+  Registers custom `contentEncoding`
+
+  Note that content assertions are disabled by default.
+  see [`Compiler::enable_content_assertions`]
+  */
+  pub fn register_content_encoding(&mut self, decoder: Decoder) {
+    self.decoders.insert(decoder.name, decoder);
+  }
+
+  /**
+  Registers custom `contentMediaType`
+
+  Note that content assertions are disabled by default.
+  see [`Compiler::enable_content_assertions`]
+  */
+  pub fn register_content_media_type(&mut self, media_type: MediaType) {
+    self.media_types.insert(media_type.name, media_type);
+  }
+
+  /**
+  Adds schema resource which used later in reference resoltion
+  If you do not know which schema resources required, then use [`UrlLoader`].
+
+  The argument `loc` can be file path or url. any fragment in `loc` is ignored.
+
+  # Errors
+
+  returns [`CompileError`] if url parsing failed.
+  */
+  pub fn add_resource(&mut self, loc: &str, json: Value) -> Result<(), CompileError> {
+    let uf = UrlFrag::absolute(loc)?;
+    self.roots.loader.add_doc(uf.url, json);
+    Ok(())
+  }
+
+  /**
+  Compile given `loc` into `target` and return an identifier to the compiled
+  schema.
+
+  the argument `loc` can be file path or url with optional fragment.
+  examples: `http://example.com/schema.json#/defs/address`,
+       `samples/schema_file.json#defs/address`
+
+  if `loc` is already compiled, it simply returns the same [`SchemaIndex`]
+   */
+  pub fn compile(
+    &mut self,
+    loc: &str,
+    target: &mut Schemas,
+  ) -> Result<SchemaIndex, CompileError> {
+    let uf = UrlFrag::absolute(loc)?;
+    // resolve anchor
+    let up = self.roots.resolve_fragment(uf)?;
+
+    let result = self.do_compile(up, target);
+    if let Err(bug @ CompileError::Bug(_)) = &result {
+      debug_assert!(false, "{bug}");
+    }
+    result
+  }
+
+  fn do_compile(
+    &mut self,
+    up: UrlPtr,
+    target: &mut Schemas,
+  ) -> Result<SchemaIndex, CompileError> {
+    let mut queue = Queue::new();
+    let mut compiled = Vec::new();
+
+    let index = queue.enqueue_schema(target, up);
+    if queue.schemas.is_empty() {
+      // already got compiled
+      return Ok(index);
+    }
+
+    while queue.schemas.len() > compiled.len() {
+      let up = &queue.schemas[compiled.len()];
+      self.roots.ensure_subschema(up)?;
+      let Some(root) = self.roots.get(&up.url) else {
+        return Err(CompileError::Bug("or_load didn't add".into()));
+      };
+      let doc = self.roots.loader.load(&root.url)?;
+      let v = up.lookup(doc)?;
+      let sch = self.compile_value(target, v, &up.clone(), root, &mut queue)?;
+      compiled.push(sch);
+      self.roots.insert(&mut queue.roots);
+    }
+
+    target.insert(queue.schemas, compiled);
+    Ok(index)
+  }
+
+  fn compile_value(
+    &self,
+    schemas: &Schemas,
+    v: &Value,
+    up: &UrlPtr,
+    root: &Root,
+    queue: &mut Queue,
+  ) -> Result<Schema, CompileError> {
+    let mut s = Schema::new(up.to_string());
+    s.draft_version = root.draft.version;
+
+    // we know it is already in queue, we just want to get its index
+    let len = queue.schemas.len();
+    s.idx = queue.enqueue_schema(schemas, up.to_owned());
+    debug_assert_eq!(queue.schemas.len(), len, "{up} should already be in queue");
+
+    s.resource = {
+      let base = UrlPtr {
+        url: up.url.clone(),
+        ptr: root.resource(&up.ptr).ptr.clone(),
+      };
+      queue.enqueue_schema(schemas, base)
+    };
+
+    // if resource, enqueue dynamicAnchors for compilation
+    if s.idx == s.resource && root.draft.version >= 2020 {
+      let res = root.resource(&up.ptr);
+      for (anchor, anchor_ptr) in &res.anchors {
+        if res.dynamic_anchors.contains(anchor) {
+          let up = UrlPtr {
+            url: up.url.clone(),
+            ptr: anchor_ptr.clone(),
+          };
+          let danchor_sch = queue.enqueue_schema(schemas, up);
+          s.dynamic_anchors.insert(anchor.to_string(), danchor_sch);
+        }
+      }
+    }
+
+    match v {
+      Value::Object(obj) => {
+        if obj.is_empty() {
+          s.boolean = Some(true);
+        } else {
+          ObjCompiler {
+            c: self,
+            obj,
+            up,
+            schemas,
+            root,
+            queue,
+          }
+          .compile_obj(&mut s)?;
+        }
+      }
+      Value::Bool(b) => s.boolean = Some(*b),
+      _ => {}
+    }
+
+    s.all_props_evaluated = s.additional_properties.is_some();
+    s.all_items_evaluated = if s.draft_version < 2020 {
+      s.additional_items.is_some() || matches!(s.items, Some(Items::SchemaRef(_)))
+    } else {
+      s.items2020.is_some()
+    };
+    s.num_items_evaluated = if let Some(Items::SchemaRefs(list)) = &s.items {
+      list.len()
+    } else {
+      s.prefix_items.len()
+    };
+
+    Ok(s)
+  }
+}
+
+struct ObjCompiler<'c, 'v, 'l, 's, 'r, 'q> {
+  c: &'c Compiler,
+  obj: &'v Map<String, Value>,
+  up: &'l UrlPtr,
+  schemas: &'s Schemas,
+  root: &'r Root,
+  queue: &'q mut Queue,
+}
+
+// compile supported drafts
+impl ObjCompiler<'_, '_, '_, '_, '_, '_> {
+  fn compile_obj(&mut self, s: &mut Schema) -> Result<(), CompileError> {
+    self.compile_draft4(s)?;
+    if self.draft_version() >= 6 {
+      self.compile_draft6(s)?;
+    }
+    if self.draft_version() >= 7 {
+      self.compile_draft7(s)?;
+    }
+    if self.draft_version() >= 2019 {
+      self.compile_draft2019(s)?;
+    }
+    if self.draft_version() >= 2020 {
+      self.compile_draft2020(s)?;
+    }
+    Ok(())
+  }
+
+  fn compile_draft4(&mut self, s: &mut Schema) -> Result<(), CompileError> {
+    if self.has_vocab("core") {
+      s.ref_ = self.enqueue_ref("$ref")?;
+      if s.ref_.is_some() && self.draft_version() < 2019 {
+        // All other properties in a "$ref" object MUST be ignored
+        return Ok(());
+      }
+    }
+
+    if self.has_vocab("applicator") {
+      s.all_of = self.enqueue_arr("allOf");
+      s.any_of = self.enqueue_arr("anyOf");
+      s.one_of = self.enqueue_arr("oneOf");
+      s.not = self.enqueue_prop("not");
+
+      if self.draft_version() < 2020 {
+        match self.value("items") {
+          Some(Value::Array(_)) => {
+            s.items = Some(Items::SchemaRefs(self.enqueue_arr("items")));
+            s.additional_items = self.enquue_additional("additionalItems");
+          }
+          _ => s.items = self.enqueue_prop("items").map(Items::SchemaRef),
+        }
+      }
+
+      s.properties = self.enqueue_map("properties");
+      s.pattern_properties = {
+        let mut v = vec![];
+        if let Some(Value::Object(obj)) = self.value("patternProperties") {
+          for pname in obj.keys() {
+            let ecma =
+              ecma::convert(pname).map_err(|src| CompileError::InvalidRegex {
+                url: self.up.format("patternProperties"),
+                regex: pname.to_owned(),
+                src,
+              })?;
+            let regex =
+              Regex::new(ecma.as_ref()).map_err(|e| CompileError::InvalidRegex {
+                url: self.up.format("patternProperties"),
+                regex: ecma.into_owned(),
+                src: e.into(),
+              })?;
+            let ptr = self.up.ptr.append2("patternProperties", pname);
+            let sch = self.enqueue_schema(ptr);
+            v.push((regex, sch));
+          }
+        }
+        v
+      };
+
+      s.additional_properties = self.enquue_additional("additionalProperties");
+
+      if let Some(Value::Object(deps)) = self.value("dependencies") {
+        s.dependencies = deps
+          .iter()
+          .filter_map(|(k, v)| {
+            let v = match v {
+              Value::Array(_) => Some(Dependency::Props(to_strings(v))),
+              _ => {
+                let ptr = self.up.ptr.append2("dependencies", k);
+                Some(Dependency::SchemaRef(self.enqueue_schema(ptr)))
+              }
+            };
+            v.map(|v| (k.clone(), v))
+          })
+          .collect();
+      }
+    }
+
+    if self.has_vocab("validation") {
+      match self.value("type") {
+        Some(Value::String(t)) => {
+          if let Some(t) = Type::from_str(t) {
+            s.types.add(t)
+          }
+        }
+        Some(Value::Array(arr)) => {
+          for t in arr {
+            if let Value::String(t) = t {
+              if let Some(t) = Type::from_str(t) {
+                s.types.add(t)
+              }
+            }
+          }
+        }
+        _ => {}
+      }
+
+      if let Some(Value::Array(e)) = self.value("enum") {
+        let mut types = Types::default();
+        for item in e {
+          types.add(Type::of(item));
+        }
+        s.enum_ = Some(Enum {
+          types,
+          values: e.clone(),
+        });
+      }
+
+      s.multiple_of = self.num("multipleOf");
+
+      s.maximum = self.num("maximum");
+      if let Some(Value::Bool(exclusive)) = self.value("exclusiveMaximum") {
+        if *exclusive {
+          s.exclusive_maximum = s.maximum.take();
+        }
+      } else {
+        s.exclusive_maximum = self.num("exclusiveMaximum");
+      }
+
+      s.minimum = self.num("minimum");
+      if let Some(Value::Bool(exclusive)) = self.value("exclusiveMinimum") {
+        if *exclusive {
+          s.exclusive_minimum = s.minimum.take();
+        }
+      } else {
+        s.exclusive_minimum = self.num("exclusiveMinimum");
+      }
+
+      s.max_length = self.usize("maxLength");
+      s.min_length = self.usize("minLength");
+
+      if let Some(Value::String(p)) = self.value("pattern") {
+        let p = ecma::convert(p).map_err(CompileError::Bug)?;
+        s.pattern = Some(Regex::new(p.as_ref()).map_err(|e| CompileError::Bug(e.into()))?);
+      }
+
+      s.max_items = self.usize("maxItems");
+      s.min_items = self.usize("minItems");
+      s.unique_items = self.bool("uniqueItems");
+
+      s.max_properties = self.usize("maxProperties");
+      s.min_properties = self.usize("minProperties");
+
+      if let Some(req) = self.value("required") {
+        s.required = to_strings(req);
+      }
+    }
+
+    // format --
+    if self.c.assert_format
+      || self.has_vocab(match self.draft_version().cmp(&2019) {
+        Ordering::Less => "core",
+        Ordering::Equal => "format",
+        Ordering::Greater => "format-assertion",
+      })
+    {
+      if let Some(Value::String(format)) = self.value("format") {
+        s.format = self
+          .c
+          .formats
+          .get(format.as_str())
+          .or_else(|| FORMATS.get(format.as_str()))
+          .cloned();
+      }
+    }
+
+    Ok(())
+  }
+
+  fn compile_draft6(&mut self, s: &mut Schema) -> Result<(), CompileError> {
+    if self.has_vocab("applicator") {
+      s.contains = self.enqueue_prop("contains");
+      s.property_names = self.enqueue_prop("propertyNames");
+    }
+
+    if self.has_vocab("validation") {
+      s.constant = self.value("const").cloned();
+    }
+
+    Ok(())
+  }
+
+  fn compile_draft7(&mut self, s: &mut Schema) -> Result<(), CompileError> {
+    if self.has_vocab("applicator") {
+      s.if_ = self.enqueue_prop("if");
+      if s.if_.is_some() {
+        if !self.bool_schema("if", false) {
+          s.then = self.enqueue_prop("then");
+        }
+        if !self.bool_schema("if", true) {
+          s.else_ = self.enqueue_prop("else");
+        }
+      }
+    }
+
+    if self.c.assert_content {
+      if let Some(Value::String(encoding)) = self.value("contentEncoding") {
+        s.content_encoding = self
+          .c
+          .decoders
+          .get(encoding.as_str())
+          .or_else(|| DECODERS.get(encoding.as_str()))
+          .cloned();
+      }
+
+      if let Some(Value::String(media_type)) = self.value("contentMediaType") {
+        s.content_media_type = self
+          .c
+          .media_types
+          .get(media_type.as_str())
+          .or_else(|| MEDIA_TYPES.get(media_type.as_str()))
+          .cloned();
+      }
+    }
+
+    Ok(())
+  }
+
+  fn compile_draft2019(&mut self, s: &mut Schema) -> Result<(), CompileError> {
+    if self.has_vocab("core") {
+      s.recursive_ref = self.enqueue_ref("$recursiveRef")?;
+      s.recursive_anchor = self.bool("$recursiveAnchor");
+    }
+
+    if self.has_vocab("validation") {
+      if s.contains.is_some() {
+        s.max_contains = self.usize("maxContains");
+        s.min_contains = self.usize("minContains");
+      }
+
+      if let Some(Value::Object(dep_req)) = self.value("dependentRequired") {
+        for (pname, pvalue) in dep_req {
+          s.dependent_required
+            .push((pname.clone(), to_strings(pvalue)));
+        }
+      }
+    }
+
+    if self.has_vocab("applicator") {
+      s.dependent_schemas = self.enqueue_map("dependentSchemas");
+    }
+
+    if self.has_vocab(match self.draft_version() {
+      2019 => "applicator",
+      _ => "unevaluated",
+    }) {
+      s.unevaluated_items = self.enqueue_prop("unevaluatedItems");
+      s.unevaluated_properties = self.enqueue_prop("unevaluatedProperties");
+    }
+
+    if self.c.assert_content
+      && s.content_media_type
+        .map(|mt| mt.json_compatible)
+        .unwrap_or(false)
+    {
+      s.content_schema = self.enqueue_prop("contentSchema");
+    }
+
+    Ok(())
+  }
+
+  fn compile_draft2020(&mut self, s: &mut Schema) -> Result<(), CompileError> {
+    if self.has_vocab("core") {
+      if let Some(sch) = self.enqueue_ref("$dynamicRef")? {
+        if let Some(Value::String(dref)) = self.value("$dynamicRef") {
+          let Ok((_, frag)) = Fragment::split(dref) else {
+            let loc = self.up.format("$dynamicRef");
+            return Err(CompileError::ParseAnchorError { loc });
+          };
+          let anchor = match frag {
+            Fragment::Anchor(Anchor(s)) => Some(s),
+            Fragment::JsonPointer(_) => None,
+          };
+          s.dynamic_ref = Some(DynamicRef { sch, anchor });
+        }
+      };
+
+      if let Some(Value::String(anchor)) = self.value("$dynamicAnchor") {
+        s.dynamic_anchor = Some(anchor.to_owned());
+      }
+    }
+
+    if self.has_vocab("applicator") {
+      s.prefix_items = self.enqueue_arr("prefixItems");
+      s.items2020 = self.enqueue_prop("items");
+    }
+
+    Ok(())
+  }
+}
+
+// enqueue helpers
+impl ObjCompiler<'_, '_, '_, '_, '_, '_> {
+  fn enqueue_schema(&mut self, ptr: JsonPointer) -> SchemaIndex {
+    let up = UrlPtr {
+      url: self.up.url.clone(),
+      ptr,
+    };
+    self.queue.enqueue_schema(self.schemas, up)
+  }
+
+  fn enqueue_prop(&mut self, pname: &'static str) -> Option<SchemaIndex> {
+    if self.obj.contains_key(pname) {
+      let ptr = self.up.ptr.append(pname);
+      Some(self.enqueue_schema(ptr))
+    } else {
+      None
+    }
+  }
+
+  fn enqueue_arr(&mut self, pname: &'static str) -> Vec<SchemaIndex> {
+    if let Some(Value::Array(arr)) = self.obj.get(pname) {
+      (0..arr.len())
+        .map(|i| {
+          let ptr = self.up.ptr.append2(pname, &i.to_string());
+          self.enqueue_schema(ptr)
+        })
+        .collect()
+    } else {
+      Vec::new()
+    }
+  }
+
+  fn enqueue_map<T>(&mut self, pname: &'static str) -> T
+  where
+    T: Default,
+    T: FromIterator<(String, SchemaIndex)>,
+  {
+    if let Some(Value::Object(obj)) = self.obj.get(pname) {
+      obj.keys()
+        .map(|k| {
+          let ptr = self.up.ptr.append2(pname, k);
+          (k.clone(), self.enqueue_schema(ptr))
+        })
+        .collect()
+    } else {
+      T::default()
+    }
+  }
+
+  fn enqueue_ref(&mut self, pname: &str) -> Result<Option<SchemaIndex>, CompileError> {
+    let Some(Value::String(ref_)) = self.obj.get(pname) else {
+      return Ok(None);
+    };
+    let base_url = self.root.base_url(&self.up.ptr);
+    let abs_ref = UrlFrag::join(base_url, ref_)?;
+    if let Some(resolved_ref) = self.root.resolve(&abs_ref)? {
+      // local ref
+      return Ok(Some(self.enqueue_schema(resolved_ref.ptr)));
+    }
+    // remote ref
+    let up = self.queue.resolve_anchor(abs_ref, &self.c.roots)?;
+    Ok(Some(self.queue.enqueue_schema(self.schemas, up)))
+  }
+
+  fn enquue_additional(&mut self, pname: &'static str) -> Option<Additional> {
+    if let Some(Value::Bool(b)) = self.obj.get(pname) {
+      Some(Additional::Bool(*b))
+    } else {
+      self.enqueue_prop(pname).map(Additional::SchemaRef)
+    }
+  }
+}
+
+// query helpers
+impl<'v> ObjCompiler<'_, 'v, '_, '_, '_, '_> {
+  fn draft_version(&self) -> usize {
+    self.root.draft.version
+  }
+
+  fn has_vocab(&self, name: &str) -> bool {
+    self.root.has_vocab(name)
+  }
+
+  fn value(&self, pname: &str) -> Option<&'v Value> {
+    self.obj.get(pname)
+  }
+
+  fn bool(&self, pname: &str) -> bool {
+    matches!(self.obj.get(pname), Some(Value::Bool(true)))
+  }
+
+  fn usize(&self, pname: &str) -> Option<usize> {
+    let Some(Value::Number(n)) = self.obj.get(pname) else {
+      return None;
+    };
+    if n.is_u64() {
+      n.as_u64().map(|n| n as usize)
+    } else {
+      n.as_f64()
+        .filter(|n| n.is_sign_positive() && n.fract() == 0.0)
+        .map(|n| n as usize)
+    }
+  }
+
+  fn num(&self, pname: &str) -> Option<Number> {
+    if let Some(Value::Number(n)) = self.obj.get(pname) {
+      Some(n.clone())
+    } else {
+      None
+    }
+  }
+
+  fn bool_schema(&self, pname: &str, b: bool) -> bool {
+    if let Some(Value::Bool(v)) = self.obj.get(pname) {
+      return *v == b;
+    }
+    false
+  }
+}
+
+/// Error type for compilation failures.
+#[derive(Debug)]
+pub enum CompileError {
+  /// Error in parsing `url`.
+  ParseUrlError { url: String, src: Box<dyn Error> },
+
+  /// Failed loading `url`.
+  LoadUrlError { url: String, src: Box<dyn Error> },
+
+  /// no [`UrlLoader`] registered for the `url`
+  UnsupportedUrlScheme { url: String },
+
+  /// Error in parsing `$schema` url.
+  InvalidMetaSchemaUrl { url: String, src: Box<dyn Error> },
+
+  /// draft `url` is not supported
+  UnsupportedDraft { url: String },
+
+  /// Cycle in resolving `$schema` in `url`.
+  MetaSchemaCycle { url: String },
+
+  /// `url` is not valid against metaschema.
+  ValidationError {
+    url: String,
+    src: ValidationError<'static, 'static>,
+  },
+
+  /// Error in parsing id at `loc`
+  ParseIdError { loc: String },
+
+  /// Error in parsing anchor at `loc`
+  ParseAnchorError { loc: String },
+
+  /// Duplicate id `id` in `url` at `ptr1` and `ptr2`.
+  DuplicateId {
+    url: String,
+    id: String,
+    ptr1: String,
+    ptr2: String,
+  },
+
+  /// Duplicate anchor `anchor` in `url` at `ptr1` and `ptr2`.
+  DuplicateAnchor {
+    anchor: String,
+    url: String,
+    ptr1: String,
+    ptr2: String,
+  },
+
+  /// Not a valid json pointer.
+  InvalidJsonPointer(String),
+
+  /// JsonPointer evaluated to nothing.
+  JsonPointerNotFound(String),
+
+  /// anchor in `reference` not found in `url`.
+  AnchorNotFound { url: String, reference: String },
+
+  /// Unsupported vocabulary `vocabulary` in `url`.
+  UnsupportedVocabulary { url: String, vocabulary: String },
+
+  /// Invalid Regex `regex` at `url`.
+  InvalidRegex {
+    url: String,
+    regex: String,
+    src: Box<dyn Error>,
+  },
+
+  /// Encountered bug in compiler implementation. Please report
+  /// this as an issue for this crate.
+  Bug(Box<dyn Error>),
+}
+
+impl Error for CompileError {
+  fn source(&self) -> Option<&(dyn Error + 'static)> {
+    match self {
+      Self::ParseUrlError { src, .. } => Some(src.as_ref()),
+      Self::LoadUrlError { src, .. } => Some(src.as_ref()),
+      Self::InvalidMetaSchemaUrl { src, .. } => Some(src.as_ref()),
+      Self::ValidationError { src, .. } => Some(src),
+      Self::Bug(src) => Some(src.as_ref()),
+      _ => None,
+    }
+  }
+}
+
+impl Display for CompileError {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    match self {
+      Self::ParseUrlError { url, src } => {
+        if f.alternate() {
+          write!(f, "error parsing url {url}: {src}")
+        } else {
+          write!(f, "error parsing {url}")
+        }
+      }
+      Self::LoadUrlError { url, src } => {
+        if f.alternate() {
+          write!(f, "error loading {url}: {src}")
+        } else {
+          write!(f, "error loading {url}")
+        }
+      }
+      Self::UnsupportedUrlScheme { url } => write!(f, "unsupported scheme in {url}"),
+      Self::InvalidMetaSchemaUrl { url, src } => {
+        if f.alternate() {
+          write!(f, "invalid $schema in {url}: {src}")
+        } else {
+          write!(f, "invalid $schema in {url}")
+        }
+      }
+      Self::UnsupportedDraft { url } => write!(f, "draft {url} is not supported"),
+      Self::MetaSchemaCycle { url } => {
+        write!(f, "cycle in resolving $schema in {url}")
+      }
+      Self::ValidationError { url, src } => {
+        if f.alternate() {
+          write!(f, "{url} is not valid against metaschema: {src}")
+        } else {
+          write!(f, "{url} is not valid against metaschema")
+        }
+      }
+      Self::ParseIdError { loc } => write!(f, "error in parsing id at {loc}"),
+      Self::ParseAnchorError { loc } => write!(f, "error in parsing anchor at {loc}"),
+      Self::DuplicateId {
+        url,
+        id,
+        ptr1,
+        ptr2,
+      } => write!(f, "duplicate $id {id} in {url} at {ptr1:?} and {ptr2:?}"),
+      Self::DuplicateAnchor {
+        anchor,
+        url,
+        ptr1,
+        ptr2,
+      } => {
+        write!(
+          f,
+          "duplicate anchor {anchor:?} in {url} at {ptr1:?} and {ptr2:?}"
+        )
+      }
+      Self::InvalidJsonPointer(loc) => write!(f, "invalid json-pointer {loc}"),
+      Self::JsonPointerNotFound(loc) => write!(f, "json-pointer in {loc} not found"),
+      Self::AnchorNotFound { url, reference } => {
+        write!(
+          f,
+          "anchor in reference {reference} is not found in schema {url}"
+        )
+      }
+      Self::UnsupportedVocabulary { url, vocabulary } => {
+        write!(f, "unsupported vocabulary {vocabulary} in {url}")
+      }
+      Self::InvalidRegex { url, regex, src } => {
+        if f.alternate() {
+          write!(f, "invalid regex {} at {url}: {src}", quote(regex))
+        } else {
+          write!(f, "invalid regex {} at {url}", quote(regex))
+        }
+      }
+      Self::Bug(src) => {
+        write!(
+          f,
+          "encountered bug in jsonschema compiler. please report: {src}"
+        )
+      }
+    }
+  }
+}
+
+// helpers --
+
+fn to_strings(v: &Value) -> Vec<String> {
+  if let Value::Array(a) = v {
+    a.iter()
+      .filter_map(|t| {
+        if let Value::String(t) = t {
+          Some(t.clone())
+        } else {
+          None
+        }
+      })
+      .collect()
+  } else {
+    vec![]
+  }
+}
+
+pub(crate) struct Queue {
+  pub(crate) schemas: Vec<UrlPtr>,
+  pub(crate) roots: HashMap<Url, Root>,
+}
+
+impl Queue {
+  fn new() -> Self {
+    Self {
+      schemas: vec![],
+      roots: HashMap::new(),
+    }
+  }
+
+  pub(crate) fn resolve_anchor(
+    &mut self,
+    uf: UrlFrag,
+    roots: &Roots,
+  ) -> Result<UrlPtr, CompileError> {
+    match uf.frag {
+      Fragment::JsonPointer(ptr) => Ok(UrlPtr { url: uf.url, ptr }),
+      Fragment::Anchor(_) => {
+        let root = match roots.get(&uf.url).or_else(|| self.roots.get(&uf.url)) {
+          Some(root) => root,
+          None => {
+            let doc = roots.loader.load(&uf.url)?;
+            let r = roots.create_root(uf.url.clone(), doc)?;
+            self.roots.entry(uf.url).or_insert(r)
+          }
+        };
+        root.resolve_fragment(&uf.frag)
+      }
+    }
+  }
+
+  pub(crate) fn enqueue_schema(&mut self, schemas: &Schemas, up: UrlPtr) -> SchemaIndex {
+    if let Some(sch) = schemas.get_by_loc(&up) {
+      // already got compiled
+      return sch.idx;
+    }
+    if let Some(qindex) = self.schemas.iter().position(|e| *e == up) {
+      // already queued for compilation
+      return SchemaIndex(schemas.size() + qindex);
+    }
+
+    // new compilation request
+    self.schemas.push(up);
+    SchemaIndex(schemas.size() + self.schemas.len() - 1)
+  }
+}

validator/src/content.rs

@@ -0,0 +1,82 @@
+use std::{collections::HashMap, error::Error};
+
+use base64::Engine;
+use once_cell::sync::Lazy;
+use serde::de::IgnoredAny;
+use serde_json::Value;
+
+// decoders --
+
+/// Defines Decoder for `contentEncoding`.
+#[derive(Clone, Copy)]
+pub struct Decoder {
+  /// Name of the encoding
+  pub name: &'static str,
+
+  /// Decodes given string to bytes
+  #[allow(clippy::type_complexity)]
+  pub func: fn(s: &str) -> Result<Vec<u8>, Box<dyn Error>>,
+}
+
+pub(crate) static DECODERS: Lazy<HashMap<&'static str, Decoder>> = Lazy::new(|| {
+  let mut m = HashMap::<&'static str, Decoder>::new();
+  m.insert(
+    "base64",
+    Decoder {
+      name: "base64",
+      func: decode_base64,
+    },
+  );
+  m
+});
+
+fn decode_base64(s: &str) -> Result<Vec<u8>, Box<dyn Error>> {
+  Ok(base64::engine::general_purpose::STANDARD.decode(s)?)
+}
+
+// mediatypes --
+
+/// Defines Mediatype for `contentMediaType`.
+#[derive(Clone, Copy)]
+pub struct MediaType {
+  /// Name of this media-type as defined in RFC 2046.
+  /// Example: `application/json`
+  pub name: &'static str,
+
+  /// whether this media type can be deserialized to json. If so it can
+  /// be validated by `contentSchema` keyword.
+  pub json_compatible: bool,
+
+  /**
+  Check whether `bytes` conforms to this media-type.
+
+  Should return `Ok(Some(Value))` if `deserialize` is `true`, otherwise it can return `Ok(None)`.
+  Ideally you could deserialize to `serde::de::IgnoredAny` if `deserialize` is `false` to gain
+  some performance.
+
+  `deserialize` is always `false` if `json_compatible` is `false`.
+  */
+  #[allow(clippy::type_complexity)]
+  pub func: fn(bytes: &[u8], deserialize: bool) -> Result<Option<Value>, Box<dyn Error>>,
+}
+
+pub(crate) static MEDIA_TYPES: Lazy<HashMap<&'static str, MediaType>> = Lazy::new(|| {
+  let mut m = HashMap::<&'static str, MediaType>::new();
+  m.insert(
+    "application/json",
+    MediaType {
+      name: "application/json",
+      json_compatible: true,
+      func: check_json,
+    },
+  );
+  m
+});
+
+fn check_json(bytes: &[u8], deserialize: bool) -> Result<Option<Value>, Box<dyn Error>> {
+  if deserialize {
+    return Ok(Some(serde_json::from_slice(bytes)?));
+  }
+  serde_json::from_slice::<IgnoredAny>(bytes)?;
+  Ok(None)
+}

validator/src/draft.rs

@@ -0,0 +1,576 @@
+use std::{
+  collections::{hash_map::Entry, HashMap},
+  str::FromStr,
+};
+
+use once_cell::sync::Lazy;
+use serde_json::{Map, Value};
+use url::Url;
+
+use crate::{compiler::*, root::Resource, util::*, SchemaIndex, Schemas};
+
+const POS_SELF: u8 = 1 << 0;
+const POS_PROP: u8 = 1 << 1;
+const POS_ITEM: u8 = 1 << 2;
+
+pub(crate) static DRAFT4: Lazy<Draft> = Lazy::new(|| Draft {
+  version: 4,
+  id: "id",
+  url: "http://json-schema.org/draft-04/schema",
+  subschemas: HashMap::from([
+    // type agnostic
+    ("definitions", POS_PROP),
+    ("not", POS_SELF),
+    ("allOf", POS_ITEM),
+    ("anyOf", POS_ITEM),
+    ("oneOf", POS_ITEM),
+    // object
+    ("properties", POS_PROP),
+    ("additionalProperties", POS_SELF),
+    ("patternProperties", POS_PROP),
+    // array
+    ("items", POS_SELF | POS_ITEM),
+    ("additionalItems", POS_SELF),
+    ("dependencies", POS_PROP),
+  ]),
+  vocab_prefix: "",
+  all_vocabs: vec![],
+  default_vocabs: vec![],
+});
+
+pub(crate) static DRAFT6: Lazy<Draft> = Lazy::new(|| {
+  let mut subschemas = DRAFT4.subschemas.clone();
+  subschemas.extend([("propertyNames", POS_SELF), ("contains", POS_SELF)]);
+  Draft {
+    version: 6,
+    id: "$id",
+    url: "http://json-schema.org/draft-06/schema",
+    subschemas,
+    vocab_prefix: "",
+    all_vocabs: vec![],
+    default_vocabs: vec![],
+  }
+});
+
+pub(crate) static DRAFT7: Lazy<Draft> = Lazy::new(|| {
+  let mut subschemas = DRAFT6.subschemas.clone();
+  subschemas.extend([("if", POS_SELF), ("then", POS_SELF), ("else", POS_SELF)]);
+  Draft {
+    version: 7,
+    id: "$id",
+    url: "http://json-schema.org/draft-07/schema",
+    subschemas,
+    vocab_prefix: "",
+    all_vocabs: vec![],
+    default_vocabs: vec![],
+  }
+});
+
+pub(crate) static DRAFT2019: Lazy<Draft> = Lazy::new(|| {
+  let mut subschemas = DRAFT7.subschemas.clone();
+  subschemas.extend([
+    ("$defs", POS_PROP),
+    ("dependentSchemas", POS_PROP),
+    ("unevaluatedProperties", POS_SELF),
+    ("unevaluatedItems", POS_SELF),
+    ("contentSchema", POS_SELF),
+  ]);
+  Draft {
+    version: 2019,
+    id: "$id",
+    url: "https://json-schema.org/draft/2019-09/schema",
+    subschemas,
+    vocab_prefix: "https://json-schema.org/draft/2019-09/vocab/",
+    all_vocabs: vec![
+      "core",
+      "applicator",
+      "validation",
+      "meta-data",
+      "format",
+      "content",
+    ],
+    default_vocabs: vec!["core", "applicator", "validation"],
+  }
+});
+
+pub(crate) static DRAFT2020: Lazy<Draft> = Lazy::new(|| {
+  let mut subschemas = DRAFT2019.subschemas.clone();
+  subschemas.extend([("prefixItems", POS_ITEM)]);
+  Draft {
+    version: 2020,
+    id: "$id",
+    url: "https://json-schema.org/draft/2020-12/schema",
+    subschemas,
+    vocab_prefix: "https://json-schema.org/draft/2020-12/vocab/",
+    all_vocabs: vec![
+      "core",
+      "applicator",
+      "unevaluated",
+      "validation",
+      "meta-data",
+      "format-annotation",
+      "format-assertion",
+      "content",
+    ],
+    default_vocabs: vec!["core", "applicator", "unevaluated", "validation"],
+  }
+});
+
+pub(crate) static STD_METASCHEMAS: Lazy<Schemas> =
+  Lazy::new(|| load_std_metaschemas().expect("std metaschemas must be compilable"));
+
+pub(crate) fn latest() -> &'static Draft {
+  crate::Draft::default().internal()
+}
+
+// --
+
+pub(crate) struct Draft {
+  pub(crate) version: usize,
+  pub(crate) url: &'static str,
+  id: &'static str,             // property name used to represent id
+  subschemas: HashMap<&'static str, u8>,  // location of subschemas
+  pub(crate) vocab_prefix: &'static str,  // prefix used for vocabulary
+  pub(crate) all_vocabs: Vec<&'static str>, // names of supported vocabs
+  pub(crate) default_vocabs: Vec<&'static str>, // names of default vocabs
+}
+
+impl Draft {
+  pub(crate) fn from_url(url: &str) -> Option<&'static Draft> {
+    let (mut url, frag) = split(url);
+    if !frag.is_empty() {
+      return None;
+    }
+    if let Some(s) = url.strip_prefix("http://") {
+      url = s;
+    }
+    if let Some(s) = url.strip_prefix("https://") {
+      url = s;
+    }
+    match url {
+      "json-schema.org/schema" => Some(latest()),
+      "json-schema.org/draft/2020-12/schema" => Some(&DRAFT2020),
+      "json-schema.org/draft/2019-09/schema" => Some(&DRAFT2019),
+      "json-schema.org/draft-07/schema" => Some(&DRAFT7),
+      "json-schema.org/draft-06/schema" => Some(&DRAFT6),
+      "json-schema.org/draft-04/schema" => Some(&DRAFT4),
+      _ => None,
+    }
+  }
+
+  fn get_schema(&self) -> Option<SchemaIndex> {
+    let url = match self.version {
+      2020 => "https://json-schema.org/draft/2020-12/schema",
+      2019 => "https://json-schema.org/draft/2019-09/schema",
+      7 => "http://json-schema.org/draft-07/schema",
+      6 => "http://json-schema.org/draft-06/schema",
+      4 => "http://json-schema.org/draft-04/schema",
+      _ => return None,
+    };
+    let up = UrlPtr {
+      url: Url::parse(url).unwrap_or_else(|_| panic!("{url} should be valid url")),
+      ptr: "".into(),
+    };
+    STD_METASCHEMAS.get_by_loc(&up).map(|s| s.idx)
+  }
+
+  pub(crate) fn validate(&self, up: &UrlPtr, v: &Value) -> Result<(), CompileError> {
+    let Some(sch) = self.get_schema() else {
+      return Err(CompileError::Bug(
+        format!("no metaschema preloaded for draft {}", self.version).into(),
+      ));
+    };
+    STD_METASCHEMAS
+      .validate(v, sch, None)
+      .map_err(|src| CompileError::ValidationError {
+        url: up.to_string(),
+        src: src.clone_static(),
+      })
+  }
+
+  fn get_id<'a>(&self, obj: &'a Map<String, Value>) -> Option<&'a str> {
+    if self.version < 2019 && obj.contains_key("$ref") {
+      return None; // All other properties in a "$ref" object MUST be ignored
+    }
+    let Some(Value::String(id)) = obj.get(self.id) else {
+      return None;
+    };
+    let (id, _) = split(id); // ignore fragment
+    Some(id).filter(|id| !id.is_empty())
+  }
+
+  pub(crate) fn get_vocabs(
+    &self,
+    url: &Url,
+    doc: &Value,
+  ) -> Result<Option<Vec<String>>, CompileError> {
+    if self.version < 2019 {
+      return Ok(None);
+    }
+    let Value::Object(obj) = doc else {
+      return Ok(None);
+    };
+
+    let Some(Value::Object(obj)) = obj.get("$vocabulary") else {
+      return Ok(None);
+    };
+
+    let mut vocabs = vec![];
+    for (vocab, reqd) in obj {
+      if let Value::Bool(true) = reqd {
+        let name = vocab
+          .strip_prefix(self.vocab_prefix)
+          .filter(|name| self.all_vocabs.contains(name));
+        if let Some(name) = name {
+          vocabs.push(name.to_owned()); // todo: avoid alloc
+        } else {
+          return Err(CompileError::UnsupportedVocabulary {
+            url: url.as_str().to_owned(),
+            vocabulary: vocab.to_owned(),
+          });
+        }
+      }
+    }
+    Ok(Some(vocabs))
+  }
+
+  // collects anchors/dynamic_achors from `sch` into `res`.
+  // note this does not collect from subschemas in sch.
+  pub(crate) fn collect_anchors(
+    &self,
+    sch: &Value,
+    sch_ptr: &JsonPointer,
+    res: &mut Resource,
+    url: &Url,
+  ) -> Result<(), CompileError> {
+    let Value::Object(obj) = sch else {
+      return Ok(());
+    };
+
+    let mut add_anchor = |anchor: Anchor| match res.anchors.entry(anchor) {
+      Entry::Occupied(entry) => {
+        if entry.get() == sch_ptr {
+          // anchor with same root_ptr already exists
+          return Ok(());
+        }
+        Err(CompileError::DuplicateAnchor {
+          url: url.as_str().to_owned(),
+          anchor: entry.key().to_string(),
+          ptr1: entry.get().to_string(),
+          ptr2: sch_ptr.to_string(),
+        })
+      }
+      entry => {
+        entry.or_insert(sch_ptr.to_owned());
+        Ok(())
+      }
+    };
+
+    if self.version < 2019 {
+      if obj.contains_key("$ref") {
+        return Ok(()); // All other properties in a "$ref" object MUST be ignored
+      }
+      // anchor is specified in id
+      if let Some(Value::String(id)) = obj.get(self.id) {
+        let Ok((_, frag)) = Fragment::split(id) else {
+          let loc = UrlFrag::format(url, sch_ptr.as_str());
+          return Err(CompileError::ParseAnchorError { loc });
+        };
+        if let Fragment::Anchor(anchor) = frag {
+          add_anchor(anchor)?;
+        };
+        return Ok(());
+      }
+    }
+    if self.version >= 2019 {
+      if let Some(Value::String(anchor)) = obj.get("$anchor") {
+        add_anchor(anchor.as_str().into())?;
+      }
+    }
+    if self.version >= 2020 {
+      if let Some(Value::String(anchor)) = obj.get("$dynamicAnchor") {
+        add_anchor(anchor.as_str().into())?;
+        res.dynamic_anchors.insert(anchor.as_str().into());
+      }
+    }
+    Ok(())
+  }
+
+  // error is json-ptr to invalid id
+  pub(crate) fn collect_resources(
+    &self,
+    sch: &Value,
+    base: &Url,      // base of json
+    sch_ptr: JsonPointer, // ptr of json
+    url: &Url,
+    resources: &mut HashMap<JsonPointer, Resource>,
+  ) -> Result<(), CompileError> {
+    if resources.contains_key(&sch_ptr) {
+      // resources are already collected
+      return Ok(());
+    }
+    if let Value::Bool(_) = sch {
+      if sch_ptr.is_empty() {
+        // root resource
+        resources.insert(sch_ptr.clone(), Resource::new(sch_ptr, base.clone()));
+      }
+      return Ok(());
+    }
+
+    let Value::Object(obj) = sch else {
+      return Ok(());
+    };
+
+    let mut base = base;
+    let tmp;
+    let res = if let Some(id) = self.get_id(obj) {
+      let Ok(id) = UrlFrag::join(base, id) else {
+        let loc = UrlFrag::format(url, sch_ptr.as_str());
+        return Err(CompileError::ParseIdError { loc });
+      };
+      tmp = id.url;
+      base = &tmp;
+      Some(Resource::new(sch_ptr.clone(), base.clone()))
+    } else if sch_ptr.is_empty() {
+      // root resource
+      Some(Resource::new(sch_ptr.clone(), base.clone()))
+    } else {
+      None
+    };
+    if let Some(res) = res {
+      if let Some(dup) = resources.values_mut().find(|res| res.id == *base) {
+        return Err(CompileError::DuplicateId {
+          url: url.to_string(),
+          id: base.to_string(),
+          ptr1: res.ptr.to_string(),
+          ptr2: dup.ptr.to_string(),
+        });
+      }
+      resources.insert(sch_ptr.clone(), res);
+    }
+
+    // collect anchors into base resource
+    if let Some(res) = resources.values_mut().find(|res| res.id == *base) {
+      self.collect_anchors(sch, &sch_ptr, res, url)?;
+    } else {
+      debug_assert!(false, "base resource must exist");
+    }
+
+    for (&kw, &pos) in &self.subschemas {
+      let Some(v) = obj.get(kw) else {
+        continue;
+      };
+      if pos & POS_SELF != 0 {
+        let ptr = sch_ptr.append(kw);
+        self.collect_resources(v, base, ptr, url, resources)?;
+      }
+      if pos & POS_ITEM != 0 {
+        if let Value::Array(arr) = v {
+          for (i, item) in arr.iter().enumerate() {
+            let ptr = sch_ptr.append2(kw, &i.to_string());
+            self.collect_resources(item, base, ptr, url, resources)?;
+          }
+        }
+      }
+      if pos & POS_PROP != 0 {
+        if let Value::Object(obj) = v {
+          for (pname, pvalue) in obj {
+            let ptr = sch_ptr.append2(kw, pname);
+            self.collect_resources(pvalue, base, ptr, url, resources)?;
+          }
+        }
+      }
+    }
+    Ok(())
+  }
+
+  pub(crate) fn is_subschema(&self, ptr: &str) -> bool {
+    if ptr.is_empty() {
+      return true;
+    }
+
+    fn split(mut ptr: &str) -> (&str, &str) {
+      ptr = &ptr[1..]; // rm `/` prefix
+      if let Some(i) = ptr.find('/') {
+        (&ptr[..i], &ptr[i..])
+      } else {
+        (ptr, "")
+      }
+    }
+
+    let (tok, ptr) = split(ptr);
+
+    if let Some(&pos) = self.subschemas.get(tok) {
+      if pos & POS_SELF != 0 && self.is_subschema(ptr) {
+        return true;
+      }
+      if !ptr.is_empty() {
+        if pos & POS_PROP != 0 {
+          let (_, ptr) = split(ptr);
+          if self.is_subschema(ptr) {
+            return true;
+          }
+        }
+        if pos & POS_ITEM != 0 {
+          let (tok, ptr) = split(ptr);
+          if usize::from_str(tok).is_ok() && self.is_subschema(ptr) {
+            return true;
+          }
+        }
+      }
+    }
+
+    false
+  }
+}
+
+fn load_std_metaschemas() -> Result<Schemas, CompileError> {
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.enable_format_assertions();
+  compiler.compile("https://json-schema.org/draft/2020-12/schema", &mut schemas)?;
+  compiler.compile("https://json-schema.org/draft/2019-09/schema", &mut schemas)?;
+  compiler.compile("http://json-schema.org/draft-07/schema", &mut schemas)?;
+  compiler.compile("http://json-schema.org/draft-06/schema", &mut schemas)?;
+  compiler.compile("http://json-schema.org/draft-04/schema", &mut schemas)?;
+  Ok(schemas)
+}
+
+#[cfg(test)]
+mod tests {
+  use crate::{Compiler, Schemas};
+
+  use super::*;
+
+  #[test]
+  fn test_meta() {
+    let mut schemas = Schemas::default();
+    let mut compiler = Compiler::default();
+    let v: Value = serde_json::from_str(include_str!("metaschemas/draft-04/schema")).unwrap();
+    let url = "https://json-schema.org/draft-04/schema";
+    compiler.add_resource(url, v).unwrap();
+    compiler.compile(url, &mut schemas).unwrap();
+  }
+
+  #[test]
+  fn test_from_url() {
+    let tests = [
+      ("http://json-schema.org/draft/2020-12/schema", Some(2020)), // http url
+      ("https://json-schema.org/draft/2020-12/schema", Some(2020)), // https url
+      ("https://json-schema.org/schema", Some(latest().version)), // latest
+      ("https://json-schema.org/draft-04/schema", Some(4)),
+    ];
+    for (url, version) in tests {
+      let got = Draft::from_url(url).map(|d| d.version);
+      assert_eq!(got, version, "for {url}");
+    }
+  }
+
+  #[test]
+  fn test_collect_ids() {
+    let url = Url::parse("http://a.com/schema.json").unwrap();
+    let json: Value = serde_json::from_str(
+      r#"{
+        "id": "http://a.com/schemas/schema.json",
+        "definitions": {
+          "s1": { "id": "http://a.com/definitions/s1" },
+          "s2": {
+            "id": "../s2",
+            "items": [
+              { "id": "http://c.com/item" },
+              { "id": "http://d.com/item" }
+            ]
+          },
+          "s3": {
+            "definitions": {
+              "s1": {
+                "id": "s3",
+                "items": {
+                  "id": "http://b.com/item"
+                }
+              }
+            }
+          },
+          "s4": { "id": "http://e.com/def#abcd" }
+        }
+      }"#,
+    )
+    .unwrap();
+
+    let want = {
+      let mut m = HashMap::new();
+      m.insert("", "http://a.com/schemas/schema.json"); // root with id
+      m.insert("/definitions/s1", "http://a.com/definitions/s1");
+      m.insert("/definitions/s2", "http://a.com/s2"); // relative id
+      m.insert("/definitions/s3/definitions/s1", "http://a.com/schemas/s3");
+      m.insert("/definitions/s3/definitions/s1/items", "http://b.com/item");
+      m.insert("/definitions/s2/items/0", "http://c.com/item");
+      m.insert("/definitions/s2/items/1", "http://d.com/item");
+      m.insert("/definitions/s4", "http://e.com/def"); // id with fragments
+      m
+    };
+    let mut got = HashMap::new();
+    DRAFT4
+      .collect_resources(&json, &url, "".into(), &url, &mut got)
+      .unwrap();
+    let got = got
+      .iter()
+      .map(|(k, v)| (k.as_str(), v.id.as_str()))
+      .collect::<HashMap<&str, &str>>();
+    assert_eq!(got, want);
+  }
+
+  #[test]
+  fn test_collect_anchors() {
+    let url = Url::parse("http://a.com/schema.json").unwrap();
+    let json: Value = serde_json::from_str(
+      r#"{
+        "$defs": {
+          "s2": {
+            "$id": "http://b.com",
+            "$anchor": "b1", 
+            "items": [
+              { "$anchor": "b2" },
+              {
+                "$id": "http//c.com",
+                "items": [
+                  {"$anchor": "c1"},
+                  {"$dynamicAnchor": "c2"}
+                ]
+              },
+              { "$dynamicAnchor": "b3" }
+            ]
+          }
+        }
+      }"#,
+    )
+    .unwrap();
+    let mut resources = HashMap::new();
+    DRAFT2020
+      .collect_resources(&json, &url, "".into(), &url, &mut resources)
+      .unwrap();
+    assert!(resources.get("").unwrap().anchors.is_empty());
+    assert_eq!(resources.get("/$defs/s2").unwrap().anchors, {
+      let mut want = HashMap::new();
+      want.insert("b1".into(), "/$defs/s2".into());
+      want.insert("b2".into(), "/$defs/s2/items/0".into());
+      want.insert("b3".into(), "/$defs/s2/items/2".into());
+      want
+    });
+    assert_eq!(resources.get("/$defs/s2/items/1").unwrap().anchors, {
+      let mut want = HashMap::new();
+      want.insert("c1".into(), "/$defs/s2/items/1/items/0".into());
+      want.insert("c2".into(), "/$defs/s2/items/1/items/1".into());
+      want
+    });
+  }
+
+  #[test]
+  fn test_is_subschema() {
+    let tests = vec![("/allOf/0", true), ("/allOf/$defs", false)];
+    for test in tests {
+      let got = DRAFT2020.is_subschema(test.0);
+      assert_eq!(got, test.1, "{}", test.0);
+    }
+  }
+}

validator/src/ecma.rs

@@ -0,0 +1,197 @@
+use std::borrow::Cow;
+
+use regex_syntax::ast::parse::Parser;
+use regex_syntax::ast::{self, *};
+
+// covert ecma regex to rust regex if possible
+// see https://262.ecma-international.org/11.0/#sec-regexp-regular-expression-objects
+pub(crate) fn convert(pattern: &str) -> Result<Cow<'_, str>, Box<dyn std::error::Error>> {
+  let mut pattern = Cow::Borrowed(pattern);
+
+  let mut ast = loop {
+    match Parser::new().parse(pattern.as_ref()) {
+      Ok(ast) => break ast,
+      Err(e) => {
+        if let Some(s) = fix_error(&e) {
+          pattern = Cow::Owned(s);
+        } else {
+          Err(e)?;
+        }
+      }
+    }
+  };
+
+  loop {
+    let translator = Translator {
+      pat: pattern.as_ref(),
+      out: None,
+    };
+    if let Some(updated_pattern) = ast::visit(&ast, translator)? {
+      match Parser::new().parse(&updated_pattern) {
+        Ok(updated_ast) => {
+          pattern = Cow::Owned(updated_pattern);
+          ast = updated_ast;
+        }
+        Err(e) => {
+          debug_assert!(
+            false,
+            "ecma::translate changed {:?} to {:?}: {e}",
+            pattern, updated_pattern
+          );
+          break;
+        }
+      }
+    } else {
+      break;
+    }
+  }
+  Ok(pattern)
+}
+
+fn fix_error(e: &Error) -> Option<String> {
+  if let ErrorKind::EscapeUnrecognized = e.kind() {
+    let (start, end) = (e.span().start.offset, e.span().end.offset);
+    let s = &e.pattern()[start..end];
+    if let r"\c" = s {
+      // handle \c{control_letter}
+      if let Some(control_letter) = e.pattern()[end..].chars().next() {
+        if control_letter.is_ascii_alphabetic() {
+          return Some(format!(
+            "{}{}{}",
+            &e.pattern()[..start],
+            ((control_letter as u8) % 32) as char,
+            &e.pattern()[end + 1..],
+          ));
+        }
+      }
+    }
+  }
+  None
+}
+
+/**
+handles following translations:
+- \d should ascii digits only. so replace with [0-9]
+- \D should match everything but ascii digits. so replace with [^0-9]
+- \w should match ascii letters only. so replace with [a-zA-Z0-9_]
+- \W should match everything but ascii letters. so replace with [^a-zA-Z0-9_]
+- \s and \S differences
+- \a is not an ECMA 262 control escape
+*/
+struct Translator<'a> {
+  pat: &'a str,
+  out: Option<String>,
+}
+
+impl Translator<'_> {
+  fn replace(&mut self, span: &Span, with: &str) {
+    let (start, end) = (span.start.offset, span.end.offset);
+    self.out = Some(format!("{}{with}{}", &self.pat[..start], &self.pat[end..]));
+  }
+
+  fn replace_class_class(&mut self, perl: &ClassPerl) {
+    match perl.kind {
+      ClassPerlKind::Digit => {
+        self.replace(&perl.span, if perl.negated { "[^0-9]" } else { "[0-9]" });
+      }
+      ClassPerlKind::Word => {
+        let with = &if perl.negated {
+          "[^A-Za-z0-9_]"
+        } else {
+          "[A-Za-z0-9_]"
+        };
+        self.replace(&perl.span, with);
+      }
+      ClassPerlKind::Space => {
+        let with = &if perl.negated {
+          "[^ \t\n\r\u{000b}\u{000c}\u{00a0}\u{feff}\u{2003}\u{2029}]"
+        } else {
+          "[ \t\n\r\u{000b}\u{000c}\u{00a0}\u{feff}\u{2003}\u{2029}]"
+        };
+        self.replace(&perl.span, with);
+      }
+    }
+  }
+}
+
+impl Visitor for Translator<'_> {
+  type Output = Option<String>;
+  type Err = &'static str;
+
+  fn finish(self) -> Result<Self::Output, Self::Err> {
+    Ok(self.out)
+  }
+
+  fn visit_class_set_item_pre(&mut self, ast: &ast::ClassSetItem) -> Result<(), Self::Err> {
+    if let ClassSetItem::Perl(perl) = ast {
+      self.replace_class_class(perl);
+    }
+    Ok(())
+  }
+
+  fn visit_post(&mut self, ast: &Ast) -> Result<(), Self::Err> {
+    if self.out.is_some() {
+      return Ok(());
+    }
+    match ast {
+      Ast::ClassPerl(perl) => {
+        self.replace_class_class(perl);
+      }
+      Ast::Literal(ref literal) => {
+        if let Literal {
+          kind: LiteralKind::Special(SpecialLiteralKind::Bell),
+          ..
+        } = literal.as_ref()
+        {
+          return Err("\\a is not an ECMA 262 control escape");
+        }
+      }
+      _ => (),
+    }
+    Ok(())
+  }
+}
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_ecma_compat_valid() {
+    // println!("{:#?}", Parser::new().parse(r#"a\a"#));
+    let tests = [
+      (r"ab\cAcde\cBfg", "ab\u{1}cde\u{2}fg"), // \c{control_letter}
+      (r"\\comment", r"\\comment"),      // there is no \c
+      (r"ab\def", r#"ab[0-9]ef"#),       // \d
+      (r"ab[a-z\d]ef", r#"ab[a-z[0-9]]ef"#),  // \d inside classSet
+      (r"ab\Def", r#"ab[^0-9]ef"#),      // \d
+      (r"ab[a-z\D]ef", r#"ab[a-z[^0-9]]ef"#), // \D inside classSet
+    ];
+    for (input, want) in tests {
+      match convert(input) {
+        Ok(got) => {
+          if got.as_ref() != want {
+            panic!("convert({input:?}): got: {got:?}, want: {want:?}");
+          }
+        }
+        Err(e) => {
+          panic!("convert({input:?}) failed: {e}");
+        }
+      }
+    }
+  }
+
+  #[test]
+  fn test_ecma_compat_invalid() {
+    // println!("{:#?}", Parser::new().parse(r#"a\a"#));
+    let tests = [
+      r"\c\n",   // \c{invalid_char}
+      r"abc\adef", // \a is not valid
+    ];
+    for input in tests {
+      if convert(input).is_ok() {
+        panic!("convert({input:?}) mut fail");
+      }
+    }
+  }
+}

validator/src/formats.rs

@@ -0,0 +1,838 @@
+use std::{
+  collections::HashMap,
+  error::Error,
+  net::{Ipv4Addr, Ipv6Addr},
+};
+
+use once_cell::sync::Lazy;
+use percent_encoding::percent_decode_str;
+use serde_json::Value;
+use url::Url;
+
+use crate::ecma;
+
+/// Defines format for `format` keyword.
+#[derive(Clone, Copy)]
+pub struct Format {
+  /// Name of the format
+  pub name: &'static str,
+
+  /// validates given value.
+  pub func: fn(v: &Value) -> Result<(), Box<dyn Error>>,
+}
+
+pub(crate) static FORMATS: Lazy<HashMap<&'static str, Format>> = Lazy::new(|| {
+  let mut m = HashMap::<&'static str, Format>::new();
+  let mut register = |name, func| m.insert(name, Format { name, func });
+  register("regex", validate_regex);
+  register("ipv4", validate_ipv4);
+  register("ipv6", validate_ipv6);
+  register("hostname", validate_hostname);
+  register("idn-hostname", validate_idn_hostname);
+  register("email", validate_email);
+  register("idn-email", validate_idn_email);
+  register("date", validate_date);
+  register("time", validate_time);
+  register("date-time", validate_date_time);
+  register("duration", validate_duration);
+  register("period", validate_period);
+  register("json-pointer", validate_json_pointer);
+  register("relative-json-pointer", validate_relative_json_pointer);
+  register("uuid", validate_uuid);
+  register("uri", validate_uri);
+  register("iri", validate_iri);
+  register("uri-reference", validate_uri_reference);
+  register("iri-reference", validate_iri_reference);
+  register("uri-template", validate_uri_template);
+  m
+});
+
+fn validate_regex(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  ecma::convert(s).map(|_| ())
+}
+
+fn validate_ipv4(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  s.parse::<Ipv4Addr>()?;
+  Ok(())
+}
+
+fn validate_ipv6(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  s.parse::<Ipv6Addr>()?;
+  Ok(())
+}
+
+fn validate_date(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_date(s)
+}
+
+fn matches_char(s: &str, index: usize, ch: char) -> bool {
+  s.is_char_boundary(index) && s[index..].starts_with(ch)
+}
+
+// see https://datatracker.ietf.org/doc/html/rfc3339#section-5.6
+fn check_date(s: &str) -> Result<(), Box<dyn Error>> {
+  // yyyy-mm-dd
+  if s.len() != 10 {
+    Err("must be 10 characters long")?;
+  }
+  if !matches_char(s, 4, '-') || !matches_char(s, 7, '-') {
+    Err("missing hyphen in correct place")?;
+  }
+
+  let mut ymd = s.splitn(3, '-').filter_map(|t| t.parse::<usize>().ok());
+  let (Some(y), Some(m), Some(d)) = (ymd.next(), ymd.next(), ymd.next()) else {
+    Err("non-positive year/month/day")?
+  };
+
+  if !matches!(m, 1..=12) {
+    Err(format!("{m} months in year"))?;
+  }
+  if !matches!(d, 1..=31) {
+    Err(format!("{d} days in month"))?;
+  }
+
+  match m {
+    2 => {
+      let mut feb_days = 28;
+      if y % 4 == 0 && (y % 100 != 0 || y % 400 == 0) {
+        feb_days += 1; // leap year
+      };
+      if d > feb_days {
+        Err(format!("february has {feb_days} days only"))?;
+      }
+    }
+    4 | 6 | 9 | 11 => {
+      if d > 30 {
+        Err("month has 30 days only")?;
+      }
+    }
+    _ => {}
+  }
+  Ok(())
+}
+
+fn validate_time(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_time(s)
+}
+
+fn check_time(mut str: &str) -> Result<(), Box<dyn Error>> {
+  // min: hh:mm:ssZ
+  if str.len() < 9 {
+    Err("less than 9 characters long")?
+  }
+  if !matches_char(str, 2, ':') || !matches_char(str, 5, ':') {
+    Err("missing colon in correct place")?
+  }
+
+  // parse hh:mm:ss
+  if !str.is_char_boundary(8) {
+    Err("contains non-ascii char")?
+  }
+  let mut hms = (str[..8])
+    .splitn(3, ':')
+    .filter_map(|t| t.parse::<usize>().ok());
+  let (Some(mut h), Some(mut m), Some(s)) = (hms.next(), hms.next(), hms.next()) else {
+    Err("non-positive hour/min/sec")?
+  };
+  if h > 23 || m > 59 || s > 60 {
+    Err("hour/min/sec out of range")?
+  }
+  str = &str[8..];
+
+  // parse sec-frac if present
+  if let Some(rem) = str.strip_prefix('.') {
+    let n_digits = rem.chars().take_while(char::is_ascii_digit).count();
+    if n_digits == 0 {
+      Err("no digits in second fraction")?;
+    }
+    str = &rem[n_digits..];
+  }
+
+  if str != "z" && str != "Z" {
+    // parse time-numoffset
+    if str.len() != 6 {
+      Err("offset must be 6 characters long")?;
+    }
+    let sign: isize = match str.chars().next() {
+      Some('+') => -1,
+      Some('-') => 1,
+      _ => return Err("offset must begin with plus/minus")?,
+    };
+    str = &str[1..];
+    if !matches_char(str, 2, ':') {
+      Err("missing colon in offset at correct place")?
+    }
+
+    let mut zhm = str.splitn(2, ':').filter_map(|t| t.parse::<usize>().ok());
+    let (Some(zh), Some(zm)) = (zhm.next(), zhm.next()) else {
+      Err("non-positive hour/min in offset")?
+    };
+    if zh > 23 || zm > 59 {
+      Err("hour/min in offset out of range")?
+    }
+
+    // apply timezone
+    let mut hm = (h * 60 + m) as isize + sign * (zh * 60 + zm) as isize;
+    if hm < 0 {
+      hm += 24 * 60;
+      debug_assert!(hm >= 0);
+    }
+    let hm = hm as usize;
+    (h, m) = (hm / 60, hm % 60);
+  }
+
+  // check leap second
+  if !(s < 60 || (h == 23 && m == 59)) {
+    Err("invalid leap second")?
+  }
+  Ok(())
+}
+
+fn validate_date_time(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_date_time(s)
+}
+
+fn check_date_time(s: &str) -> Result<(), Box<dyn Error>> {
+  // min: yyyy-mm-ddThh:mm:ssZ
+  if s.len() < 20 {
+    Err("less than 20 characters long")?;
+  }
+  if !s.is_char_boundary(10) || !s[10..].starts_with(['t', 'T']) {
+    Err("11th character must be t or T")?;
+  }
+  if let Err(e) = check_date(&s[..10]) {
+    Err(format!("invalid date element: {e}"))?;
+  }
+  if let Err(e) = check_time(&s[11..]) {
+    Err(format!("invalid time element: {e}"))?;
+  }
+  Ok(())
+}
+
+fn validate_duration(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_duration(s)
+}
+
+// see https://datatracker.ietf.org/doc/html/rfc3339#appendix-A
+fn check_duration(s: &str) -> Result<(), Box<dyn Error>> {
+  // must start with 'P'
+  let Some(s) = s.strip_prefix('P') else {
+    Err("must start with P")?
+  };
+  if s.is_empty() {
+    Err("nothing after P")?
+  }
+
+  // dur-week
+  if let Some(s) = s.strip_suffix('W') {
+    if s.is_empty() {
+      Err("no number in week")?
+    }
+    if !s.chars().all(|c| c.is_ascii_digit()) {
+      Err("invalid week")?
+    }
+    return Ok(());
+  }
+
+  static UNITS: [&str; 2] = ["YMD", "HMS"];
+  for (i, s) in s.split('T').enumerate() {
+    let mut s = s;
+    if i != 0 && s.is_empty() {
+      Err("no time elements")?
+    }
+    let Some(mut units) = UNITS.get(i).cloned() else {
+      Err("more than one T")?
+    };
+    while !s.is_empty() {
+      let digit_count = s.chars().take_while(char::is_ascii_digit).count();
+      if digit_count == 0 {
+        Err("missing number")?
+      }
+      s = &s[digit_count..];
+      let Some(unit) = s.chars().next() else {
+        Err("missing unit")?
+      };
+      let Some(j) = units.find(unit) else {
+        if UNITS[i].contains(unit) {
+          Err(format!("unit {unit} out of order"))?
+        }
+        Err(format!("invalid unit {unit}"))?
+      };
+      units = &units[j + 1..];
+      s = &s[1..];
+    }
+  }
+
+  Ok(())
+}
+
+// see https://datatracker.ietf.org/doc/html/rfc3339#appendix-A
+fn validate_period(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+
+  let Some(slash) = s.find('/') else {
+    Err("missing slash")?
+  };
+
+  let (start, end) = (&s[..slash], &s[slash + 1..]);
+  if start.starts_with('P') {
+    if let Err(e) = check_duration(start) {
+      Err(format!("invalid start duration: {e}"))?
+    }
+    if let Err(e) = check_date_time(end) {
+      Err(format!("invalid end date-time: {e}"))?
+    }
+  } else {
+    if let Err(e) = check_date_time(start) {
+      Err(format!("invalid start date-time: {e}"))?
+    }
+    if end.starts_with('P') {
+      if let Err(e) = check_duration(end) {
+        Err(format!("invalid end duration: {e}"))?;
+      }
+    } else if let Err(e) = check_date_time(end) {
+      Err(format!("invalid end date-time: {e}"))?;
+    }
+  }
+  Ok(())
+}
+
+fn validate_hostname(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_hostname(s)
+}
+
+// see https://en.wikipedia.org/wiki/Hostname#Restrictions_on_valid_host_names
+fn check_hostname(mut s: &str) -> Result<(), Box<dyn Error>> {
+  // entire hostname (including the delimiting dots but not a trailing dot) has a maximum of 253 ASCII characters
+  s = s.strip_suffix('.').unwrap_or(s);
+  if s.len() > 253 {
+    Err("more than 253 characters long")?
+  }
+
+  // Hostnames are composed of series of labels concatenated with dots, as are all domain names
+  for label in s.split('.') {
+    // Each label must be from 1 to 63 characters long
+    if !matches!(label.len(), 1..=63) {
+      Err("label must be 1 to 63 characters long")?;
+    }
+
+    // labels must not start or end with a hyphen
+    if label.starts_with('-') {
+      Err("label starts with hyphen")?;
+    }
+
+    if label.ends_with('-') {
+      Err("label ends with hyphen")?;
+    }
+
+    // labels may contain only the ASCII letters 'a' through 'z' (in a case-insensitive manner),
+    // the digits '0' through '9', and the hyphen ('-')
+    if let Some(ch) = label
+      .chars()
+      .find(|c| !matches!(c, 'a'..='z' | 'A'..='Z' | '0'..='9' | '-'))
+    {
+      Err(format!("invalid character {ch:?}"))?;
+    }
+  }
+
+  Ok(())
+}
+
+fn validate_idn_hostname(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_idn_hostname(s)
+}
+
+fn check_idn_hostname(s: &str) -> Result<(), Box<dyn Error>> {
+  let s = idna::domain_to_ascii_strict(s)?;
+  let unicode = idna::domain_to_unicode(&s).0;
+
+  // see https://www.rfc-editor.org/rfc/rfc5892#section-2.6
+  {
+    static DISALLOWED: [char; 10] = [
+      '\u{0640}', // ARABIC TATWEEL
+      '\u{07FA}', // NKO LAJANYALAN
+      '\u{302E}', // HANGUL SINGLE DOT TONE MARK
+      '\u{302F}', // HANGUL DOUBLE DOT TONE MARK
+      '\u{3031}', // VERTICAL KANA REPEAT MARK
+      '\u{3032}', // VERTICAL KANA REPEAT WITH VOICED SOUND MARK
+      '\u{3033}', // VERTICAL KANA REPEAT MARK UPPER HALF
+      '\u{3034}', // VERTICAL KANA REPEAT WITH VOICED SOUND MARK UPPER HA
+      '\u{3035}', // VERTICAL KANA REPEAT MARK LOWER HALF
+      '\u{303B}', // VERTICAL IDEOGRAPHIC ITERATION MARK
+    ];
+    if unicode.contains(DISALLOWED) {
+      Err("contains disallowed character")?;
+    }
+  }
+
+  // unicode string must not contain "--" in 3rd and 4th position
+  // and must not start and end with a '-'
+  // see https://www.rfc-editor.org/rfc/rfc5891#section-4.2.3.1
+  {
+    let count: usize = unicode
+      .chars()
+      .skip(2)
+      .take(2)
+      .map(|c| if c == '-' { 1 } else { 0 })
+      .sum();
+    if count == 2 {
+      Err("unicode string must not contain '--' in 3rd and 4th position")?;
+    }
+  }
+
+  // MIDDLE DOT is allowed between 'l' characters only
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.3
+  {
+    let middle_dot = '\u{00b7}';
+    let mut s = unicode.as_str();
+    while let Some(i) = s.find(middle_dot) {
+      let prefix = &s[..i];
+      let suffix = &s[i + middle_dot.len_utf8()..];
+      if !prefix.ends_with('l') || !suffix.ends_with('l') {
+        Err("MIDDLE DOT is allowed between 'l' characters only")?;
+      }
+      s = suffix;
+    }
+  }
+
+  // Greek KERAIA must be followed by Greek character
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.4
+  {
+    let keralia = '\u{0375}';
+    let greek = '\u{0370}'..='\u{03FF}';
+    let mut s = unicode.as_str();
+    while let Some(i) = s.find(keralia) {
+      let suffix = &s[i + keralia.len_utf8()..];
+      if !suffix.starts_with(|c| greek.contains(&c)) {
+        Err("Greek KERAIA must be followed by Greek character")?;
+      }
+      s = suffix;
+    }
+  }
+
+  // Hebrew GERESH must be preceded by Hebrew character
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.5
+  //
+  // Hebrew GERSHAYIM must be preceded by Hebrew character
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.6
+  {
+    let geresh = '\u{05F3}';
+    let gereshayim = '\u{05F4}';
+    let hebrew = '\u{0590}'..='\u{05FF}';
+    for ch in [geresh, gereshayim] {
+      let mut s = unicode.as_str();
+      while let Some(i) = s.find(ch) {
+        let prefix = &s[..i];
+        let suffix = &s[i + ch.len_utf8()..];
+        if !prefix.ends_with(|c| hebrew.contains(&c)) {
+          if i == 0 {
+            Err("Hebrew GERESH must be preceded by Hebrew character")?;
+          } else {
+            Err("Hebrew GERESHYIM must be preceded by Hebrew character")?;
+          }
+        }
+        s = suffix;
+      }
+    }
+  }
+
+  // KATAKANA MIDDLE DOT must be with Hiragana, Katakana, or Han
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.7
+  {
+    let katakana_middle_dot = '\u{30FB}';
+    let hiragana = '\u{3040}'..='\u{309F}';
+    let katakana = '\u{30A0}'..='\u{30FF}';
+    let han = '\u{4E00}'..='\u{9FFF}'; // https://en.wikipedia.org/wiki/CJK_Unified_Ideographs_(Unicode_block): is this range correct??
+    if unicode.contains(katakana_middle_dot) {
+      if unicode.contains(|c| hiragana.contains(&c))
+        || unicode.contains(|c| c != katakana_middle_dot && katakana.contains(&c))
+        || unicode.contains(|c| han.contains(&c))
+      {
+        // ok
+      } else {
+        Err("KATAKANA MIDDLE DOT must be with Hiragana, Katakana, or Han")?;
+      }
+    }
+  }
+
+  // ARABIC-INDIC DIGITS and Extended Arabic-Indic Digits cannot be mixed
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.8
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.9
+  {
+    let arabic_indic_digits = '\u{0660}'..='\u{0669}';
+    let extended_arabic_indic_digits = '\u{06F0}'..='\u{06F9}';
+    if unicode.contains(|c| arabic_indic_digits.contains(&c))
+      && unicode.contains(|c| extended_arabic_indic_digits.contains(&c))
+    {
+      Err("ARABIC-INDIC DIGITS and Extended Arabic-Indic Digits cannot be mixed")?;
+    }
+  }
+
+  // ZERO WIDTH JOINER must be preceded by Virama
+  // see https://www.rfc-editor.org/rfc/rfc5892#appendix-A.2
+  {
+    let zero_width_jointer = '\u{200D}';
+    static VIRAMA: [char; 61] = [
+      '\u{094D}',
+      '\u{09CD}',
+      '\u{0A4D}',
+      '\u{0ACD}',
+      '\u{0B4D}',
+      '\u{0BCD}',
+      '\u{0C4D}',
+      '\u{0CCD}',
+      '\u{0D3B}',
+      '\u{0D3C}',
+      '\u{0D4D}',
+      '\u{0DCA}',
+      '\u{0E3A}',
+      '\u{0EBA}',
+      '\u{0F84}',
+      '\u{1039}',
+      '\u{103A}',
+      '\u{1714}',
+      '\u{1734}',
+      '\u{17D2}',
+      '\u{1A60}',
+      '\u{1B44}',
+      '\u{1BAA}',
+      '\u{1BAB}',
+      '\u{1BF2}',
+      '\u{1BF3}',
+      '\u{2D7F}',
+      '\u{A806}',
+      '\u{A82C}',
+      '\u{A8C4}',
+      '\u{A953}',
+      '\u{A9C0}',
+      '\u{AAF6}',
+      '\u{ABED}',
+      '\u{10A3F}',
+      '\u{11046}',
+      '\u{1107F}',
+      '\u{110B9}',
+      '\u{11133}',
+      '\u{11134}',
+      '\u{111C0}',
+      '\u{11235}',
+      '\u{112EA}',
+      '\u{1134D}',
+      '\u{11442}',
+      '\u{114C2}',
+      '\u{115BF}',
+      '\u{1163F}',
+      '\u{116B6}',
+      '\u{1172B}',
+      '\u{11839}',
+      '\u{1193D}',
+      '\u{1193E}',
+      '\u{119E0}',
+      '\u{11A34}',
+      '\u{11A47}',
+      '\u{11A99}',
+      '\u{11C3F}',
+      '\u{11D44}',
+      '\u{11D45}',
+      '\u{11D97}',
+    ]; // https://www.compart.com/en/unicode/combining/9
+    let mut s = unicode.as_str();
+    while let Some(i) = s.find(zero_width_jointer) {
+      let prefix = &s[..i];
+      let suffix = &s[i + zero_width_jointer.len_utf8()..];
+      if !prefix.ends_with(VIRAMA) {
+        Err("ZERO WIDTH JOINER must be preceded by Virama")?;
+      }
+      s = suffix;
+    }
+  }
+
+  check_hostname(&s)
+}
+
+fn validate_email(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_email(s)
+}
+
+// see https://en.wikipedia.org/wiki/Email_address
+fn check_email(s: &str) -> Result<(), Box<dyn Error>> {
+  // entire email address to be no more than 254 characters long
+  if s.len() > 254 {
+    Err("more than 254 characters long")?
+  }
+
+  // email address is generally recognized as having two parts joined with an at-sign
+  let Some(at) = s.rfind('@') else {
+    Err("missing @")?
+  };
+  let (local, domain) = (&s[..at], &s[at + 1..]);
+
+  // local part may be up to 64 characters long
+  if local.len() > 64 {
+    Err("local part more than 64 characters long")?
+  }
+
+  if local.len() > 1 && local.starts_with('"') && local.ends_with('"') {
+    // quoted
+    let local = &local[1..local.len() - 1];
+    if local.contains(['\\', '"']) {
+      Err("backslash and quote not allowed within quoted local part")?
+    }
+  } else {
+    // unquoted
+
+    if local.starts_with('.') {
+      Err("starts with dot")?
+    }
+    if local.ends_with('.') {
+      Err("ends with dot")?
+    }
+
+    // consecutive dots not allowed
+    if local.contains("..") {
+      Err("consecutive dots")?
+    }
+
+    // check allowd chars
+    if let Some(ch) = local
+      .chars()
+      .find(|c| !(c.is_ascii_alphanumeric() || ".!#$%&'*+-/=?^_`{|}~".contains(*c)))
+    {
+      Err(format!("invalid character {ch:?}"))?
+    }
+  }
+
+  // domain if enclosed in brackets, must match an IP address
+  if domain.starts_with('[') && domain.ends_with(']') {
+    let s = &domain[1..domain.len() - 1];
+    if let Some(s) = s.strip_prefix("IPv6:") {
+      if let Err(e) = s.parse::<Ipv6Addr>() {
+        Err(format!("invalid ipv6 address: {e}"))?
+      }
+      return Ok(());
+    }
+    if let Err(e) = s.parse::<Ipv4Addr>() {
+      Err(format!("invalid ipv4 address: {e}"))?
+    }
+    return Ok(());
+  }
+
+  // domain must match the requirements for a hostname
+  if let Err(e) = check_hostname(domain) {
+    Err(format!("invalid domain: {e}"))?
+  }
+
+  Ok(())
+}
+
+fn validate_idn_email(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+
+  let Some(at) = s.rfind('@') else {
+    Err("missing @")?
+  };
+  let (local, domain) = (&s[..at], &s[at + 1..]);
+
+  let local = idna::domain_to_ascii_strict(local)?;
+  let domain = idna::domain_to_ascii_strict(domain)?;
+  if let Err(e) = check_idn_hostname(&domain) {
+    Err(format!("invalid domain: {e}"))?
+  }
+  check_email(&format!("{local}@{domain}"))
+}
+
+fn validate_json_pointer(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  check_json_pointer(s)
+}
+
+// see https://www.rfc-editor.org/rfc/rfc6901#section-3
+fn check_json_pointer(s: &str) -> Result<(), Box<dyn Error>> {
+  if s.is_empty() {
+    return Ok(());
+  }
+  if !s.starts_with('/') {
+    Err("not starting with slash")?;
+  }
+  for token in s.split('/').skip(1) {
+    let mut chars = token.chars();
+    while let Some(ch) = chars.next() {
+      if ch == '~' {
+        if !matches!(chars.next(), Some('0' | '1')) {
+          Err("~ must be followed by 0 or 1")?;
+        }
+      } else if !matches!(ch, '\x00'..='\x2E' | '\x30'..='\x7D' | '\x7F'..='\u{10FFFF}') {
+        Err("contains disallowed character")?;
+      }
+    }
+  }
+  Ok(())
+}
+
+// see https://tools.ietf.org/html/draft-handrews-relative-json-pointer-01#section-3
+fn validate_relative_json_pointer(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+
+  // start with non-negative-integer
+  let num_digits = s.chars().take_while(char::is_ascii_digit).count();
+  if num_digits == 0 {
+    Err("must start with non-negative integer")?;
+  }
+  if num_digits > 1 && s.starts_with('0') {
+    Err("starts with zero")?;
+  }
+  let s = &s[num_digits..];
+
+  // followed by either json-pointer or '#'
+  if s == "#" {
+    return Ok(());
+  }
+  if let Err(e) = check_json_pointer(s) {
+    Err(format!("invalid json-pointer element: {e}"))?;
+  }
+  Ok(())
+}
+
+// see https://datatracker.ietf.org/doc/html/rfc4122#page-4
+fn validate_uuid(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+
+  static HEX_GROUPS: [usize; 5] = [8, 4, 4, 4, 12];
+  let mut i = 0;
+  for group in s.split('-') {
+    if i >= HEX_GROUPS.len() {
+      Err("more than 5 elements")?;
+    }
+    if group.len() != HEX_GROUPS[i] {
+      Err(format!(
+        "element {} must be {} characters long",
+        i + 1,
+        HEX_GROUPS[i]
+      ))?;
+    }
+    if let Some(ch) = group.chars().find(|c| !c.is_ascii_hexdigit()) {
+      Err(format!("non-hex character {ch:?}"))?;
+    }
+    i += 1;
+  }
+  if i != HEX_GROUPS.len() {
+    Err("must have 5 elements")?;
+  }
+  Ok(())
+}
+
+fn validate_uri(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  if fluent_uri::UriRef::parse(s.as_str())?.scheme().is_none() {
+    Err("relative url")?;
+  };
+  Ok(())
+}
+
+fn validate_iri(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  match Url::parse(s) {
+    Ok(_) => Ok(()),
+    Err(url::ParseError::RelativeUrlWithoutBase) => Err("relative url")?,
+    Err(e) => Err(e)?,
+  }
+}
+
+static TEMP_URL: Lazy<Url> = Lazy::new(|| Url::parse("http://temp.com").unwrap());
+
+fn parse_uri_reference(s: &str) -> Result<Url, Box<dyn Error>> {
+  if s.contains('\\') {
+    Err("contains \\\\")?;
+  }
+  Ok(TEMP_URL.join(s)?)
+}
+
+fn validate_uri_reference(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  fluent_uri::UriRef::parse(s.as_str())?;
+  Ok(())
+}
+
+fn validate_iri_reference(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+  parse_uri_reference(s)?;
+  Ok(())
+}
+
+fn validate_uri_template(v: &Value) -> Result<(), Box<dyn Error>> {
+  let Value::String(s) = v else {
+    return Ok(());
+  };
+
+  let url = parse_uri_reference(s)?;
+
+  let path = url.path();
+  // path we got has curly bases percent encoded
+  let path = percent_decode_str(path).decode_utf8()?;
+
+  // ensure curly brackets are not nested and balanced
+  for part in path.as_ref().split('/') {
+    let mut want = true;
+    for got in part
+      .chars()
+      .filter(|c| matches!(c, '{' | '}'))
+      .map(|c| c == '{')
+    {
+      if got != want {
+        Err("nested curly braces")?;
+      }
+      want = !want;
+    }
+    if !want {
+      Err("no matching closing brace")?
+    }
+  }
+  Ok(())
+}

validator/src/lib.rs

@@ -0,0 +1,724 @@
+/*! This crate supports JsonSchema validation for drafts `2020-12`, `2019-09`, `7`, `6` and `4`.
+
+```rust,no_run
+# use std::fs::File;
+# use std::error::Error;
+# use boon::*;
+# use serde_json::Value;
+# fn main() -> Result<(), Box<dyn Error>>{
+let mut schemas = Schemas::new(); // container for compiled schemas
+let mut compiler = Compiler::new();
+let sch_index = compiler.compile("schema.json", &mut schemas)?;
+let instance: Value = serde_json::from_reader(File::open("instance.json")?)?;
+let valid = schemas.validate(&instance, sch_index, None).is_ok();
+# Ok(())
+# }
+```
+
+If schema file has no `$schema`, it assumes latest draft.
+You can override this:
+```rust,no_run
+# use boon::*;
+# let mut compiler = Compiler::new();
+compiler.set_default_draft(Draft::V7);
+```
+
+The use of this option is HIGHLY encouraged to ensure continued
+correct operation of your schema. The current default value will
+not stay the same over time.
+
+# Examples
+
+- [example_from_strings]: loading schemas from Strings
+- [example_from_https]: loading schemas from `http(s)`
+- [example_custom_format]: registering custom format
+- [example_custom_content_encoding]: registering custom contentEncoding
+- [example_custom_content_media_type]: registering custom contentMediaType
+
+# Compile Errors
+
+```no_compile
+println!("{compile_error}");
+println!("{compile_error:#}"); // prints cause if any
+```
+
+Using alterate form in display will print cause if any.
+This will be useful in cases like [`CompileError::LoadUrlError`],
+as it would be useful to know whether the url does not exist or
+the resource at url is not a valid json document.
+
+# Validation Errors
+
+[`ValidationError`] may have multiple `causes` resulting
+in tree of errors.
+
+`println!("{validation_error}")` prints:
+```no_compile
+jsonschema validation failed with file:///tmp/customer.json#
+ at '': missing properties 'age'
+ at '/billing_address': missing properties 'street_address', 'city', 'state'
+```
+
+
+The alternate form `println!("{validation_error:#}")` prints:
+```no_compile
+jsonschema validation failed with file:///tmp/customer.json#
+ [I#] [S#/required] missing properties 'age'
+ [I#/billing_address] [S#/properties/billing_address/$ref] validation failed with file:///tmp/address.json#
+  [I#/billing_address] [S#/required] missing properties 'street_address', 'city', 'state'
+```
+here `I` refers to the instance document and `S` refers to last schema document.
+
+for example:
+- after line 1: `S` refers to `file:///tmp/customer.json`
+- after line 3: `S` refers to `file://tmp/address.json`
+
+
+# Output Formats
+
+[`ValidationError`] can be converted into following output formats:
+- [flag] `validation_error.flag_output()`
+- [basic] `validation_error.basic_output()`
+- [detailed] `validation_error.detailed_output()`
+
+The output object implements `serde::Serialize`.
+
+It also implement `Display` to print json:
+
+```no_compile
+println!("{output}"); // prints unformatted json
+println!("{output:#}"); // prints indented json
+```
+
+[example_from_strings]: https://github.com/santhosh-tekuri/boon/blob/d466730e5e5c7c663bd6739e74e39d1e2f7baae4/tests/examples.rs#L22
+[example_from_https]: https://github.com/santhosh-tekuri/boon/blob/d466730e5e5c7c663bd6739e74e39d1e2f7baae4/tests/examples.rs#L62
+[example_from_yaml_files]: https://github.com/santhosh-tekuri/boon/blob/d466730e5e5c7c663bd6739e74e39d1e2f7baae4/tests/examples.rs#L86
+[example_custom_format]: https://github.com/santhosh-tekuri/boon/blob/d466730e5e5c7c663bd6739e74e39d1e2f7baae4/tests/examples.rs#L119
+[example_custom_content_encoding]: https://github.com/santhosh-tekuri/boon/blob/d466730e5e5c7c663bd6739e74e39d1e2f7baae4/tests/examples.rs#L153
+[example_custom_content_media_type]: https://github.com/santhosh-tekuri/boon/blob/d466730e5e5c7c663bd6739e74e39d1e2f7baae4/tests/examples.rs#L198
+[flag]: https://json-schema.org/draft/2020-12/json-schema-core.html#name-flag
+[basic]: https://json-schema.org/draft/2020-12/json-schema-core.html#name-basic
+[detailed]: https://json-schema.org/draft/2020-12/json-schema-core.html#name-detailed
+
+*/
+
+mod compiler;
+mod content;
+mod draft;
+mod ecma;
+mod formats;
+mod loader;
+mod output;
+mod root;
+mod roots;
+mod util;
+mod validator;
+
+#[cfg(not(target_arch = "wasm32"))]
+pub use loader::FileLoader;
+pub use {
+  compiler::{CompileError, Compiler, Draft},
+  content::{Decoder, MediaType},
+  formats::Format,
+  loader::{SchemeUrlLoader, UrlLoader},
+  output::{
+    AbsoluteKeywordLocation, FlagOutput, KeywordPath, OutputError, OutputUnit, SchemaToken,
+  },
+  validator::{InstanceLocation, InstanceToken},
+};
+
+use std::{borrow::Cow, collections::HashMap, error::Error, fmt::Display};
+
+use ahash::AHashMap;
+use regex::Regex;
+use serde_json::{Number, Value};
+use util::*;
+
+/// Options for validation process
+#[derive(Default, Debug, Clone, Copy)]
+pub struct ValidationOptions {
+  /// treat unevaluated properties as an error
+  pub be_strict: bool,
+}
+
+/// Identifier to compiled schema.
+#[derive(Default, Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct SchemaIndex(usize);
+
+/// Collection of compiled schemas.
+#[derive(Default)]
+pub struct Schemas {
+  list: Vec<Schema>,
+  map: HashMap<UrlPtr, usize>, // loc => schema-index
+}
+
+impl Schemas {
+  pub fn new() -> Self {
+    Self::default()
+  }
+
+  fn insert(&mut self, locs: Vec<UrlPtr>, compiled: Vec<Schema>) {
+    for (up, sch) in locs.into_iter().zip(compiled.into_iter()) {
+      let i = self.list.len();
+      self.list.push(sch);
+      self.map.insert(up, i);
+    }
+  }
+
+  fn get(&self, idx: SchemaIndex) -> &Schema {
+    &self.list[idx.0] // todo: return bug
+  }
+
+  fn get_by_loc(&self, up: &UrlPtr) -> Option<&Schema> {
+    self.map.get(up).and_then(|&i| self.list.get(i))
+  }
+
+  /// Returns true if `sch_index` is generated for this instance.
+  pub fn contains(&self, sch_index: SchemaIndex) -> bool {
+    self.list.get(sch_index.0).is_some()
+  }
+
+  pub fn size(&self) -> usize {
+    self.list.len()
+  }
+
+  /**
+  Validates `v` with schema identified by `sch_index`
+
+  # Panics
+
+  Panics if `sch_index` is not generated for this instance.
+  [`Schemas::contains`] can be used too ensure that it does not panic.
+  */
+  pub fn validate<'s, 'v>(
+    &'s self,
+    v: &'v Value,
+    sch_index: SchemaIndex,
+    options: Option<&'s ValidationOptions>,
+  ) -> Result<(), ValidationError<'s, 'v>> {
+    let Some(sch) = self.list.get(sch_index.0) else {
+      panic!("Schemas::validate: schema index out of bounds");
+    };
+    validator::validate(v, sch, self, options)
+  }
+}
+
+#[derive(Default)]
+struct Schema {
+  draft_version: usize,
+  idx: SchemaIndex,
+  loc: String,
+  resource: SchemaIndex,
+  dynamic_anchors: HashMap<String, SchemaIndex>,
+  all_props_evaluated: bool,
+  all_items_evaluated: bool,
+  num_items_evaluated: usize,
+
+  // type agnostic --
+  boolean: Option<bool>, // boolean schema
+  ref_: Option<SchemaIndex>,
+  recursive_ref: Option<SchemaIndex>,
+  recursive_anchor: bool,
+  dynamic_ref: Option<DynamicRef>,
+  dynamic_anchor: Option<String>,
+  types: Types,
+  enum_: Option<Enum>,
+  constant: Option<Value>,
+  not: Option<SchemaIndex>,
+  all_of: Vec<SchemaIndex>,
+  any_of: Vec<SchemaIndex>,
+  one_of: Vec<SchemaIndex>,
+  if_: Option<SchemaIndex>,
+  then: Option<SchemaIndex>,
+  else_: Option<SchemaIndex>,
+  format: Option<Format>,
+
+  // object --
+  min_properties: Option<usize>,
+  max_properties: Option<usize>,
+  required: Vec<String>,
+  properties: AHashMap<String, SchemaIndex>,
+  pattern_properties: Vec<(Regex, SchemaIndex)>,
+  property_names: Option<SchemaIndex>,
+  additional_properties: Option<Additional>,
+  dependent_required: Vec<(String, Vec<String>)>,
+  dependent_schemas: Vec<(String, SchemaIndex)>,
+  dependencies: Vec<(String, Dependency)>,
+  unevaluated_properties: Option<SchemaIndex>,
+
+  // array --
+  min_items: Option<usize>,
+  max_items: Option<usize>,
+  unique_items: bool,
+  min_contains: Option<usize>,
+  max_contains: Option<usize>,
+  contains: Option<SchemaIndex>,
+  items: Option<Items>,
+  additional_items: Option<Additional>,
+  prefix_items: Vec<SchemaIndex>,
+  items2020: Option<SchemaIndex>,
+  unevaluated_items: Option<SchemaIndex>,
+
+  // string --
+  min_length: Option<usize>,
+  max_length: Option<usize>,
+  pattern: Option<Regex>,
+  content_encoding: Option<Decoder>,
+  content_media_type: Option<MediaType>,
+  content_schema: Option<SchemaIndex>,
+
+  // number --
+  minimum: Option<Number>,
+  maximum: Option<Number>,
+  exclusive_minimum: Option<Number>,
+  exclusive_maximum: Option<Number>,
+  multiple_of: Option<Number>,
+}
+
+#[derive(Debug)]
+struct Enum {
+  /// types that occur in enum
+  types: Types,
+  /// values in enum
+  values: Vec<Value>,
+}
+
+#[derive(Debug)]
+enum Items {
+  SchemaRef(SchemaIndex),
+  SchemaRefs(Vec<SchemaIndex>),
+}
+
+#[derive(Debug)]
+enum Additional {
+  Bool(bool),
+  SchemaRef(SchemaIndex),
+}
+
+#[derive(Debug)]
+enum Dependency {
+  Props(Vec<String>),
+  SchemaRef(SchemaIndex),
+}
+
+struct DynamicRef {
+  sch: SchemaIndex,
+  anchor: Option<String>,
+}
+
+impl Schema {
+  fn new(loc: String) -> Self {
+    Self {
+      loc,
+      ..Default::default()
+    }
+  }
+}
+
+/// JSON data types for JSONSchema
+#[derive(Debug, PartialEq, Clone, Copy)]
+pub enum Type {
+  Null = 1,
+  Boolean = 2,
+  Number = 4,
+  Integer = 8,
+  String = 16,
+  Array = 32,
+  Object = 64,
+}
+
+impl Type {
+  fn of(v: &Value) -> Self {
+    match v {
+      Value::Null => Type::Null,
+      Value::Bool(_) => Type::Boolean,
+      Value::Number(_) => Type::Number,
+      Value::String(_) => Type::String,
+      Value::Array(_) => Type::Array,
+      Value::Object(_) => Type::Object,
+    }
+  }
+
+  fn from_str(value: &str) -> Option<Self> {
+    match value {
+      "null" => Some(Self::Null),
+      "boolean" => Some(Self::Boolean),
+      "number" => Some(Self::Number),
+      "integer" => Some(Self::Integer),
+      "string" => Some(Self::String),
+      "array" => Some(Self::Array),
+      "object" => Some(Self::Object),
+      _ => None,
+    }
+  }
+
+  fn primitive(v: &Value) -> bool {
+    !matches!(Self::of(v), Self::Array | Self::Object)
+  }
+}
+
+impl Display for Type {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    match self {
+      Type::Null => write!(f, "null"),
+      Type::Boolean => write!(f, "boolean"),
+      Type::Number => write!(f, "number"),
+      Type::Integer => write!(f, "integer"),
+      Type::String => write!(f, "string"),
+      Type::Array => write!(f, "array"),
+      Type::Object => write!(f, "object"),
+    }
+  }
+}
+
+/// Set of [`Type`]s
+#[derive(Debug, Default, Clone, Copy)]
+pub struct Types(u8);
+
+impl Types {
+  fn is_empty(self) -> bool {
+    self.0 == 0
+  }
+
+  fn add(&mut self, t: Type) {
+    self.0 |= t as u8;
+  }
+
+  /// Returns `true` if this set contains given type.
+  pub fn contains(&self, t: Type) -> bool {
+    self.0 & t as u8 != 0
+  }
+
+  /// Returns an iterator over types.
+  pub fn iter(&self) -> impl Iterator<Item = Type> + '_ {
+    static TYPES: [Type; 7] = [
+      Type::Null,
+      Type::Boolean,
+      Type::Number,
+      Type::Integer,
+      Type::String,
+      Type::Array,
+      Type::Object,
+    ];
+    TYPES.iter().cloned().filter(|t| self.contains(*t))
+  }
+}
+
+impl FromIterator<Type> for Types {
+  fn from_iter<T: IntoIterator<Item = Type>>(iter: T) -> Self {
+    let mut types = Types::default();
+    for t in iter {
+      types.add(t);
+    }
+    types
+  }
+}
+
+/// Error type for validation failures.
+#[derive(Debug)]
+pub struct ValidationError<'s, 'v> {
+  /// The absolute, dereferenced schema location.
+  pub schema_url: &'s str,
+  /// The location of the JSON value within the instance being validated
+  pub instance_location: InstanceLocation<'v>,
+  /// kind of error
+  pub kind: ErrorKind<'s, 'v>,
+  /// Holds nested errors
+  pub causes: Vec<ValidationError<'s, 'v>>,
+}
+
+impl Error for ValidationError<'_, '_> {}
+
+/// A list specifying general categories of validation errors.
+#[derive(Debug)]
+pub enum ErrorKind<'s, 'v> {
+  Group,
+  Schema {
+    url: &'s str,
+  },
+  ContentSchema,
+  PropertyName {
+    prop: String,
+  },
+  Reference {
+    kw: &'static str,
+    url: &'s str,
+  },
+  RefCycle {
+    url: &'s str,
+    kw_loc1: String,
+    kw_loc2: String,
+  },
+  FalseSchema,
+  Type {
+    got: Type,
+    want: Types,
+  },
+  Enum {
+    want: &'s Vec<Value>,
+  },
+  Const {
+    want: &'s Value,
+  },
+  Format {
+    got: Cow<'v, Value>,
+    want: &'static str,
+    err: Box<dyn Error>,
+  },
+  MinProperties {
+    got: usize,
+    want: usize,
+  },
+  MaxProperties {
+    got: usize,
+    want: usize,
+  },
+  AdditionalProperties {
+    got: Vec<Cow<'v, str>>,
+  },
+  Required {
+    want: Vec<&'s str>,
+  },
+  Dependency {
+    /// dependency of prop that failed.
+    prop: &'s str,
+    /// missing props.
+    missing: Vec<&'s str>,
+  },
+  DependentRequired {
+    /// dependency of prop that failed.
+    prop: &'s str,
+    /// missing props.
+    missing: Vec<&'s str>,
+  },
+  MinItems {
+    got: usize,
+    want: usize,
+  },
+  MaxItems {
+    got: usize,
+    want: usize,
+  },
+  Contains,
+  MinContains {
+    got: Vec<usize>,
+    want: usize,
+  },
+  MaxContains {
+    got: Vec<usize>,
+    want: usize,
+  },
+  UniqueItems {
+    got: [usize; 2],
+  },
+  AdditionalItems {
+    got: usize,
+  },
+  MinLength {
+    got: usize,
+    want: usize,
+  },
+  MaxLength {
+    got: usize,
+    want: usize,
+  },
+  Pattern {
+    got: Cow<'v, str>,
+    want: &'s str,
+  },
+  ContentEncoding {
+    want: &'static str,
+    err: Box<dyn Error>,
+  },
+  ContentMediaType {
+    got: Vec<u8>,
+    want: &'static str,
+    err: Box<dyn Error>,
+  },
+  Minimum {
+    got: Cow<'v, Number>,
+    want: &'s Number,
+  },
+  Maximum {
+    got: Cow<'v, Number>,
+    want: &'s Number,
+  },
+  ExclusiveMinimum {
+    got: Cow<'v, Number>,
+    want: &'s Number,
+  },
+  ExclusiveMaximum {
+    got: Cow<'v, Number>,
+    want: &'s Number,
+  },
+  MultipleOf {
+    got: Cow<'v, Number>,
+    want: &'s Number,
+  },
+  Not,
+  /// none of the subschemas matched
+  AllOf,
+  /// none of the subschemas matched.
+  AnyOf,
+  /// - `None`: none of the schemas matched.
+  /// - Some(i, j): subschemas at i, j matched
+  OneOf(Option<(usize, usize)>),
+}
+
+impl Display for ErrorKind<'_, '_> {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    match self {
+      Self::Group => write!(f, "validation failed"),
+      Self::Schema { url } => write!(f, "validation failed with {url}"),
+      Self::ContentSchema => write!(f, "contentSchema failed"),
+      Self::PropertyName { prop } => write!(f, "invalid property {}", quote(prop)),
+      Self::Reference { .. } => {
+        write!(f, "validation failed")
+      }
+      Self::RefCycle {
+        url,
+        kw_loc1,
+        kw_loc2,
+      } => write!(
+        f,
+        "both {} and {} resolve to {url} causing reference cycle",
+        quote(&kw_loc1.to_string()),
+        quote(&kw_loc2.to_string())
+      ),
+      Self::FalseSchema => write!(f, "false schema"),
+      Self::Type { got, want } => {
+        // todo: why join not working for Type struct ??
+        let want = join_iter(want.iter(), " or ");
+        write!(f, "want {want}, but got {got}",)
+      }
+      Self::Enum { want } => {
+        if want.iter().all(Type::primitive) {
+          if want.len() == 1 {
+            write!(f, "value must be ")?;
+            display(f, &want[0])
+          } else {
+            let want = join_iter(want.iter().map(string), ", ");
+            write!(f, "value must be one of {want}")
+          }
+        } else {
+          write!(f, "enum failed")
+        }
+      }
+      Self::Const { want } => {
+        if Type::primitive(want) {
+          write!(f, "value must be ")?;
+          display(f, want)
+        } else {
+          write!(f, "const failed")
+        }
+      }
+      Self::Format { got, want, err } => {
+        display(f, got)?;
+        write!(f, " is not valid {want}: {err}")
+      }
+      Self::MinProperties { got, want } => write!(
+        f,
+        "minimum {want} properties required, but got {got} properties"
+      ),
+      Self::MaxProperties { got, want } => write!(
+        f,
+        "maximum {want} properties required, but got {got} properties"
+      ),
+      Self::AdditionalProperties { got } => {
+        write!(
+          f,
+          "additionalProperties {} not allowed",
+          join_iter(got.iter().map(quote), ", ")
+        )
+      }
+      Self::Required { want } => write!(
+        f,
+        "missing properties {}",
+        join_iter(want.iter().map(quote), ", ")
+      ),
+      Self::Dependency { prop, missing } => {
+        write!(
+          f,
+          "properties {} required, if {} property exists",
+          join_iter(missing.iter().map(quote), ", "),
+          quote(prop)
+        )
+      }
+      Self::DependentRequired { prop, missing } => write!(
+        f,
+        "properties {} required, if {} property exists",
+        join_iter(missing.iter().map(quote), ", "),
+        quote(prop)
+      ),
+      Self::MinItems { got, want } => {
+        write!(f, "minimum {want} items required, but got {got} items")
+      }
+      Self::MaxItems { got, want } => {
+        write!(f, "maximum {want} items required, but got {got} items")
+      }
+      Self::MinContains { got, want } => {
+        if got.is_empty() {
+          write!(
+            f,
+            "minimum {want} items required to match contains schema, but found none",
+          )
+        } else {
+          write!(
+            f,
+            "minimum {want} items required to match contains schema, but found {} items at {}",
+            got.len(),
+            join_iter(got, ", ")
+          )
+        }
+      }
+      Self::Contains => write!(f, "no items match contains schema"),
+      Self::MaxContains { got, want } => {
+        write!(
+            f,
+            "maximum {want} items required to match contains schema, but found {} items at {}",
+            got.len(),
+            join_iter(got, ", ")
+          )
+      }
+      Self::UniqueItems { got: [i, j] } => write!(f, "items at {i} and {j} are equal"),
+      Self::AdditionalItems { got } => write!(f, "last {got} additionalItems not allowed"),
+      Self::MinLength { got, want } => write!(f, "length must be >={want}, but got {got}"),
+      Self::MaxLength { got, want } => write!(f, "length must be <={want}, but got {got}"),
+      Self::Pattern { got, want } => {
+        write!(f, "{} does not match pattern {}", quote(got), quote(want))
+      }
+      Self::ContentEncoding { want, err } => {
+        write!(f, "value is not {} encoded: {err}", quote(want))
+      }
+      Self::ContentMediaType { want, err, .. } => {
+        write!(f, "value is not of mediatype {}: {err}", quote(want))
+      }
+      Self::Minimum { got, want } => write!(f, "must be >={want}, but got {got}"),
+      Self::Maximum { got, want } => write!(f, "must be <={want}, but got {got}"),
+      Self::ExclusiveMinimum { got, want } => write!(f, "must be > {want} but got {got}"),
+      Self::ExclusiveMaximum { got, want } => write!(f, "must be < {want} but got {got}"),
+      Self::MultipleOf { got, want } => write!(f, "{got} is not multipleOf {want}"),
+      Self::Not => write!(f, "not failed"),
+      Self::AllOf => write!(f, "allOf failed",),
+      Self::AnyOf => write!(f, "anyOf failed"),
+      Self::OneOf(None) => write!(f, "oneOf failed, none matched"),
+      Self::OneOf(Some((i, j))) => write!(f, "oneOf failed, subschemas {i}, {j} matched"),
+    }
+  }
+}
+
+fn display(f: &mut std::fmt::Formatter, v: &Value) -> std::fmt::Result {
+  match v {
+    Value::String(s) => write!(f, "{}", quote(s)),
+    Value::Array(_) | Value::Object(_) => write!(f, "value"),
+    _ => write!(f, "{v}"),
+  }
+}
+
+fn string(primitive: &Value) -> String {
+  if let Value::String(s) = primitive {
+    quote(s)
+  } else {
+    format!("{primitive}")
+  }
+}

validator/src/loader.rs

@@ -0,0 +1,243 @@
+use std::{
+  cell::RefCell,
+  collections::{HashMap, HashSet},
+  error::Error,
+};
+
+#[cfg(not(target_arch = "wasm32"))]
+use std::fs::File;
+
+use appendlist::AppendList;
+use once_cell::sync::Lazy;
+use serde_json::Value;
+use url::Url;
+
+use crate::{
+  compiler::CompileError,
+  draft::{latest, Draft},
+  util::split,
+  UrlPtr,
+};
+
+/// A trait for loading json from given `url`
+pub trait UrlLoader {
+  /// Loads json from given absolute `url`.
+  fn load(&self, url: &str) -> Result<Value, Box<dyn Error>>;
+}
+
+// --
+
+#[cfg(not(target_arch = "wasm32"))]
+pub struct FileLoader;
+
+#[cfg(not(target_arch = "wasm32"))]
+impl UrlLoader for FileLoader {
+  fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+    let url = Url::parse(url)?;
+    let path = url.to_file_path().map_err(|_| "invalid file path")?;
+    let file = File::open(path)?;
+    Ok(serde_json::from_reader(file)?)
+  }
+}
+
+// --
+
+#[derive(Default)]
+pub struct SchemeUrlLoader {
+  loaders: HashMap<&'static str, Box<dyn UrlLoader>>,
+}
+
+impl SchemeUrlLoader {
+  pub fn new() -> Self {
+    Self::default()
+  }
+
+  /// Registers [`UrlLoader`] for given url `scheme`
+  pub fn register(&mut self, scheme: &'static str, url_loader: Box<dyn UrlLoader>) {
+    self.loaders.insert(scheme, url_loader);
+  }
+}
+
+impl UrlLoader for SchemeUrlLoader {
+  fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+    let url = Url::parse(url)?;
+    let Some(loader) = self.loaders.get(url.scheme()) else {
+      return Err(CompileError::UnsupportedUrlScheme {
+        url: url.as_str().to_owned(),
+      }
+      .into());
+    };
+    loader.load(url.as_str())
+  }
+}
+
+// --
+
+pub(crate) struct DefaultUrlLoader {
+  doc_map: RefCell<HashMap<Url, usize>>,
+  doc_list: AppendList<Value>,
+  loader: Box<dyn UrlLoader>,
+}
+
+impl DefaultUrlLoader {
+  #[cfg_attr(target_arch = "wasm32", allow(unused_mut))]
+  pub fn new() -> Self {
+    let mut loader = SchemeUrlLoader::new();
+    #[cfg(not(target_arch = "wasm32"))]
+    loader.register("file", Box::new(FileLoader));
+    Self {
+      doc_map: Default::default(),
+      doc_list: AppendList::new(),
+      loader: Box::new(loader),
+    }
+  }
+
+  pub fn get_doc(&self, url: &Url) -> Option<&Value> {
+    self.doc_map
+      .borrow()
+      .get(url)
+      .and_then(|i| self.doc_list.get(*i))
+  }
+
+  pub fn add_doc(&self, url: Url, json: Value) {
+    if self.get_doc(&url).is_some() {
+      return;
+    }
+    self.doc_list.push(json);
+    self.doc_map
+      .borrow_mut()
+      .insert(url, self.doc_list.len() - 1);
+  }
+
+  pub fn use_loader(&mut self, loader: Box<dyn UrlLoader>) {
+    self.loader = loader;
+  }
+
+  pub(crate) fn load(&self, url: &Url) -> Result<&Value, CompileError> {
+    if let Some(doc) = self.get_doc(url) {
+      return Ok(doc);
+    }
+
+    // check in STD_METAFILES
+    let doc = if let Some(content) = load_std_meta(url.as_str()) {
+      serde_json::from_str::<Value>(content).map_err(|e| CompileError::LoadUrlError {
+        url: url.to_string(),
+        src: e.into(),
+      })?
+    } else {
+      self.loader
+        .load(url.as_str())
+        .map_err(|src| CompileError::LoadUrlError {
+          url: url.as_str().to_owned(),
+          src,
+        })?
+    };
+    self.add_doc(url.clone(), doc);
+    self.get_doc(url)
+      .ok_or(CompileError::Bug("doc must exist".into()))
+  }
+
+  pub(crate) fn get_draft(
+    &self,
+    up: &UrlPtr,
+    doc: &Value,
+    default_draft: &'static Draft,
+    mut cycle: HashSet<Url>,
+  ) -> Result<&'static Draft, CompileError> {
+    let Value::Object(obj) = &doc else {
+      return Ok(default_draft);
+    };
+    let Some(Value::String(sch)) = obj.get("$schema") else {
+      return Ok(default_draft);
+    };
+    if let Some(draft) = Draft::from_url(sch) {
+      return Ok(draft);
+    }
+    let (sch, _) = split(sch);
+    let sch = Url::parse(sch).map_err(|e| CompileError::InvalidMetaSchemaUrl {
+      url: up.to_string(),
+      src: e.into(),
+    })?;
+    if up.ptr.is_empty() && sch == up.url {
+      return Err(CompileError::UnsupportedDraft { url: sch.into() });
+    }
+    if !cycle.insert(sch.clone()) {
+      return Err(CompileError::MetaSchemaCycle { url: sch.into() });
+    }
+
+    let doc = self.load(&sch)?;
+    let up = UrlPtr {
+      url: sch,
+      ptr: "".into(),
+    };
+    self.get_draft(&up, doc, default_draft, cycle)
+  }
+
+  pub(crate) fn get_meta_vocabs(
+    &self,
+    doc: &Value,
+    draft: &'static Draft,
+  ) -> Result<Option<Vec<String>>, CompileError> {
+    let Value::Object(obj) = &doc else {
+      return Ok(None);
+    };
+    let Some(Value::String(sch)) = obj.get("$schema") else {
+      return Ok(None);
+    };
+    if Draft::from_url(sch).is_some() {
+      return Ok(None);
+    }
+    let (sch, _) = split(sch);
+    let sch = Url::parse(sch).map_err(|e| CompileError::ParseUrlError {
+      url: sch.to_string(),
+      src: e.into(),
+    })?;
+    let doc = self.load(&sch)?;
+    draft.get_vocabs(&sch, doc)
+  }
+}
+
+pub(crate) static STD_METAFILES: Lazy<HashMap<String, &str>> = Lazy::new(|| {
+  let mut files = HashMap::new();
+  macro_rules! add {
+    ($path:expr) => {
+      files.insert(
+        $path["metaschemas/".len()..].to_owned(),
+        include_str!($path),
+      );
+    };
+  }
+  add!("metaschemas/draft-04/schema");
+  add!("metaschemas/draft-06/schema");
+  add!("metaschemas/draft-07/schema");
+  add!("metaschemas/draft/2019-09/schema");
+  add!("metaschemas/draft/2019-09/meta/core");
+  add!("metaschemas/draft/2019-09/meta/applicator");
+  add!("metaschemas/draft/2019-09/meta/validation");
+  add!("metaschemas/draft/2019-09/meta/meta-data");
+  add!("metaschemas/draft/2019-09/meta/format");
+  add!("metaschemas/draft/2019-09/meta/content");
+  add!("metaschemas/draft/2020-12/schema");
+  add!("metaschemas/draft/2020-12/meta/core");
+  add!("metaschemas/draft/2020-12/meta/applicator");
+  add!("metaschemas/draft/2020-12/meta/unevaluated");
+  add!("metaschemas/draft/2020-12/meta/validation");
+  add!("metaschemas/draft/2020-12/meta/meta-data");
+  add!("metaschemas/draft/2020-12/meta/content");
+  add!("metaschemas/draft/2020-12/meta/format-annotation");
+  add!("metaschemas/draft/2020-12/meta/format-assertion");
+  files
+});
+
+fn load_std_meta(url: &str) -> Option<&'static str> {
+  let meta = url
+    .strip_prefix("http://json-schema.org/")
+    .or_else(|| url.strip_prefix("https://json-schema.org/"));
+  if let Some(meta) = meta {
+    if meta == "schema" {
+      return load_std_meta(latest().url);
+    }
+    return STD_METAFILES.get(meta).cloned();
+  }
+  None
+}

validator/src/metaschemas/draft-04/schema

@@ -0,0 +1,151 @@
+{
+	"$schema": "http://json-schema.org/draft-04/schema#",
+	"description": "Core schema meta-schema",
+	"definitions": {
+		"schemaArray": {
+			"type": "array",
+			"minItems": 1,
+			"items": { "$ref": "#" }
+		},
+		"positiveInteger": {
+			"type": "integer",
+			"minimum": 0
+		},
+		"positiveIntegerDefault0": {
+			"allOf": [ { "$ref": "#/definitions/positiveInteger" }, { "default": 0 } ]
+		},
+		"simpleTypes": {
+			"enum": [ "array", "boolean", "integer", "null", "number", "object", "string" ]
+		},
+		"stringArray": {
+			"type": "array",
+			"items": { "type": "string" },
+			"minItems": 1,
+			"uniqueItems": true
+		}
+	},
+	"type": "object",
+	"properties": {
+		"id": {
+			"type": "string",
+			"format": "uriref"
+		},
+		"$schema": {
+			"type": "string",
+			"format": "uri"
+		},
+		"title": {
+			"type": "string"
+		},
+		"description": {
+			"type": "string"
+		},
+		"default": {},
+		"multipleOf": {
+			"type": "number",
+			"minimum": 0,
+			"exclusiveMinimum": true
+		},
+		"maximum": {
+			"type": "number"
+		},
+		"exclusiveMaximum": {
+			"type": "boolean",
+			"default": false
+		},
+		"minimum": {
+			"type": "number"
+		},
+		"exclusiveMinimum": {
+			"type": "boolean",
+			"default": false
+		},
+		"maxLength": { "$ref": "#/definitions/positiveInteger" },
+		"minLength": { "$ref": "#/definitions/positiveIntegerDefault0" },
+		"pattern": {
+			"type": "string",
+			"format": "regex"
+		},
+		"additionalItems": {
+			"anyOf": [
+				{ "type": "boolean" },
+				{ "$ref": "#" }
+			],
+			"default": {}
+		},
+		"items": {
+			"anyOf": [
+				{ "$ref": "#" },
+				{ "$ref": "#/definitions/schemaArray" }
+			],
+			"default": {}
+		},
+		"maxItems": { "$ref": "#/definitions/positiveInteger" },
+		"minItems": { "$ref": "#/definitions/positiveIntegerDefault0" },
+		"uniqueItems": {
+			"type": "boolean",
+			"default": false
+		},
+		"maxProperties": { "$ref": "#/definitions/positiveInteger" },
+		"minProperties": { "$ref": "#/definitions/positiveIntegerDefault0" },
+		"required": { "$ref": "#/definitions/stringArray" },
+		"additionalProperties": {
+			"anyOf": [
+				{ "type": "boolean" },
+				{ "$ref": "#" }
+			],
+			"default": {}
+		},
+		"definitions": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"properties": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"patternProperties": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"dependencies": {
+			"type": "object",
+			"additionalProperties": {
+				"anyOf": [
+					{ "$ref": "#" },
+					{ "$ref": "#/definitions/stringArray" }
+				]
+			}
+		},
+		"enum": {
+			"type": "array",
+			"minItems": 1,
+			"uniqueItems": true
+		},
+		"type": {
+			"anyOf": [
+				{ "$ref": "#/definitions/simpleTypes" },
+				{
+					"type": "array",
+					"items": { "$ref": "#/definitions/simpleTypes" },
+					"minItems": 1,
+					"uniqueItems": true
+				}
+			]
+		},
+		"allOf": { "$ref": "#/definitions/schemaArray" },
+		"anyOf": { "$ref": "#/definitions/schemaArray" },
+		"oneOf": { "$ref": "#/definitions/schemaArray" },
+		"not": { "$ref": "#" },
+		"format": { "type": "string" },
+		"$ref": { "type": "string" }
+	},
+	"dependencies": {
+		"exclusiveMaximum": [ "maximum" ],
+		"exclusiveMinimum": [ "minimum" ]
+	},
+	"default": {}
+}

validator/src/metaschemas/draft-06/schema

@@ -0,0 +1,151 @@
+{
+	"$schema": "http://json-schema.org/draft-06/schema#",
+	"$id": "http://json-schema.org/draft-06/schema#",
+	"title": "Core schema meta-schema",
+	"definitions": {
+		"schemaArray": {
+			"type": "array",
+			"minItems": 1,
+			"items": { "$ref": "#" }
+		},
+		"nonNegativeInteger": {
+			"type": "integer",
+			"minimum": 0
+		},
+		"nonNegativeIntegerDefault0": {
+			"allOf": [
+				{ "$ref": "#/definitions/nonNegativeInteger" },
+				{ "default": 0 }
+			]
+		},
+		"simpleTypes": {
+			"enum": [
+				"array",
+				"boolean",
+				"integer",
+				"null",
+				"number",
+				"object",
+				"string"
+			]
+		},
+		"stringArray": {
+			"type": "array",
+			"items": { "type": "string" },
+			"uniqueItems": true,
+			"default": []
+		}
+	},
+	"type": ["object", "boolean"],
+	"properties": {
+		"$id": {
+			"type": "string",
+			"format": "uri-reference"
+		},
+		"$schema": {
+			"type": "string",
+			"format": "uri"
+		},
+		"$ref": {
+			"type": "string",
+			"format": "uri-reference"
+		},
+		"title": {
+			"type": "string"
+		},
+		"description": {
+			"type": "string"
+		},
+		"default": {},
+		"multipleOf": {
+			"type": "number",
+			"exclusiveMinimum": 0
+		},
+		"maximum": {
+			"type": "number"
+		},
+		"exclusiveMaximum": {
+			"type": "number"
+		},
+		"minimum": {
+			"type": "number"
+		},
+		"exclusiveMinimum": {
+			"type": "number"
+		},
+		"maxLength": { "$ref": "#/definitions/nonNegativeInteger" },
+		"minLength": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+		"pattern": {
+			"type": "string",
+			"format": "regex"
+		},
+		"additionalItems": { "$ref": "#" },
+		"items": {
+			"anyOf": [
+				{ "$ref": "#" },
+				{ "$ref": "#/definitions/schemaArray" }
+			],
+			"default": {}
+		},
+		"maxItems": { "$ref": "#/definitions/nonNegativeInteger" },
+		"minItems": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+		"uniqueItems": {
+			"type": "boolean",
+			"default": false
+		},
+		"contains": { "$ref": "#" },
+		"maxProperties": { "$ref": "#/definitions/nonNegativeInteger" },
+		"minProperties": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+		"required": { "$ref": "#/definitions/stringArray" },
+		"additionalProperties": { "$ref": "#" },
+		"definitions": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"properties": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"patternProperties": {
+			"type": "object",
+			"regexProperties": true,
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"dependencies": {
+			"type": "object",
+			"additionalProperties": {
+				"anyOf": [
+					{ "$ref": "#" },
+					{ "$ref": "#/definitions/stringArray" }
+				]
+			}
+		},
+		"propertyNames": { "$ref": "#" },
+		"const": {},
+		"enum": {
+			"type": "array",
+			"minItems": 1,
+			"uniqueItems": true
+		},
+		"type": {
+			"anyOf": [
+				{ "$ref": "#/definitions/simpleTypes" },
+				{
+					"type": "array",
+					"items": { "$ref": "#/definitions/simpleTypes" },
+					"minItems": 1,
+					"uniqueItems": true
+				}
+			]
+		},
+		"format": { "type": "string" },
+		"allOf": { "$ref": "#/definitions/schemaArray" },
+		"anyOf": { "$ref": "#/definitions/schemaArray" },
+		"oneOf": { "$ref": "#/definitions/schemaArray" },
+		"not": { "$ref": "#" }
+	},
+	"default": {}
+}

validator/src/metaschemas/draft-07/schema

@@ -0,0 +1,172 @@
+{
+	"$schema": "http://json-schema.org/draft-07/schema#",
+	"$id": "http://json-schema.org/draft-07/schema#",
+	"title": "Core schema meta-schema",
+	"definitions": {
+		"schemaArray": {
+			"type": "array",
+			"minItems": 1,
+			"items": { "$ref": "#" }
+		},
+		"nonNegativeInteger": {
+			"type": "integer",
+			"minimum": 0
+		},
+		"nonNegativeIntegerDefault0": {
+			"allOf": [
+				{ "$ref": "#/definitions/nonNegativeInteger" },
+				{ "default": 0 }
+			]
+		},
+		"simpleTypes": {
+			"enum": [
+				"array",
+				"boolean",
+				"integer",
+				"null",
+				"number",
+				"object",
+				"string"
+			]
+		},
+		"stringArray": {
+			"type": "array",
+			"items": { "type": "string" },
+			"uniqueItems": true,
+			"default": []
+		}
+	},
+	"type": ["object", "boolean"],
+	"properties": {
+		"$id": {
+			"type": "string",
+			"format": "uri-reference"
+		},
+		"$schema": {
+			"type": "string",
+			"format": "uri"
+		},
+		"$ref": {
+			"type": "string",
+			"format": "uri-reference"
+		},
+		"$comment": {
+			"type": "string"
+		},
+		"title": {
+			"type": "string"
+		},
+		"description": {
+			"type": "string"
+		},
+		"default": true,
+		"readOnly": {
+			"type": "boolean",
+			"default": false
+		},
+		"writeOnly": {
+			"type": "boolean",
+			"default": false
+		},
+		"examples": {
+			"type": "array",
+			"items": true
+		},
+		"multipleOf": {
+			"type": "number",
+			"exclusiveMinimum": 0
+		},
+		"maximum": {
+			"type": "number"
+		},
+		"exclusiveMaximum": {
+			"type": "number"
+		},
+		"minimum": {
+			"type": "number"
+		},
+		"exclusiveMinimum": {
+			"type": "number"
+		},
+		"maxLength": { "$ref": "#/definitions/nonNegativeInteger" },
+		"minLength": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+		"pattern": {
+			"type": "string",
+			"format": "regex"
+		},
+		"additionalItems": { "$ref": "#" },
+		"items": {
+			"anyOf": [
+				{ "$ref": "#" },
+				{ "$ref": "#/definitions/schemaArray" }
+			],
+			"default": true
+		},
+		"maxItems": { "$ref": "#/definitions/nonNegativeInteger" },
+		"minItems": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+		"uniqueItems": {
+			"type": "boolean",
+			"default": false
+		},
+		"contains": { "$ref": "#" },
+		"maxProperties": { "$ref": "#/definitions/nonNegativeInteger" },
+		"minProperties": { "$ref": "#/definitions/nonNegativeIntegerDefault0" },
+		"required": { "$ref": "#/definitions/stringArray" },
+		"additionalProperties": { "$ref": "#" },
+		"definitions": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"properties": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"default": {}
+		},
+		"patternProperties": {
+			"type": "object",
+			"additionalProperties": { "$ref": "#" },
+			"propertyNames": { "format": "regex" },
+			"default": {}
+		},
+		"dependencies": {
+			"type": "object",
+			"additionalProperties": {
+				"anyOf": [
+					{ "$ref": "#" },
+					{ "$ref": "#/definitions/stringArray" }
+				]
+			}
+		},
+		"propertyNames": { "$ref": "#" },
+		"const": true,
+		"enum": {
+			"type": "array",
+			"items": true,
+			"minItems": 1,
+			"uniqueItems": true
+		},
+		"type": {
+			"anyOf": [
+				{ "$ref": "#/definitions/simpleTypes" },
+				{
+					"type": "array",
+					"items": { "$ref": "#/definitions/simpleTypes" },
+					"minItems": 1,
+					"uniqueItems": true
+				}
+			]
+		},
+		"format": { "type": "string" },
+		"contentMediaType": { "type": "string" },
+		"contentEncoding": { "type": "string" },
+		"if": { "$ref": "#" },
+		"then": { "$ref": "#" },
+		"else": { "$ref": "#" },
+		"allOf": { "$ref": "#/definitions/schemaArray" },
+		"anyOf": { "$ref": "#/definitions/schemaArray" },
+		"oneOf": { "$ref": "#/definitions/schemaArray" },
+		"not": { "$ref": "#" }
+	},
+	"default": true
+}

validator/src/metaschemas/draft/2019-09/meta/applicator

@@ -0,0 +1,55 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/meta/applicator",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/applicator": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Applicator vocabulary meta-schema",
+	"type": ["object", "boolean"],
+	"properties": {
+		"additionalItems": { "$recursiveRef": "#" },
+		"unevaluatedItems": { "$recursiveRef": "#" },
+		"items": {
+			"anyOf": [
+				{ "$recursiveRef": "#" },
+				{ "$ref": "#/$defs/schemaArray" }
+			]
+		},
+		"contains": { "$recursiveRef": "#" },
+		"additionalProperties": { "$recursiveRef": "#" },
+		"unevaluatedProperties": { "$recursiveRef": "#" },
+		"properties": {
+			"type": "object",
+			"additionalProperties": { "$recursiveRef": "#" },
+			"default": {}
+		},
+		"patternProperties": {
+			"type": "object",
+			"additionalProperties": { "$recursiveRef": "#" },
+			"propertyNames": { "format": "regex" },
+			"default": {}
+		},
+		"dependentSchemas": {
+			"type": "object",
+			"additionalProperties": {
+				"$recursiveRef": "#"
+			}
+		},
+		"propertyNames": { "$recursiveRef": "#" },
+		"if": { "$recursiveRef": "#" },
+		"then": { "$recursiveRef": "#" },
+		"else": { "$recursiveRef": "#" },
+		"allOf": { "$ref": "#/$defs/schemaArray" },
+		"anyOf": { "$ref": "#/$defs/schemaArray" },
+		"oneOf": { "$ref": "#/$defs/schemaArray" },
+		"not": { "$recursiveRef": "#" }
+	},
+	"$defs": {
+		"schemaArray": {
+			"type": "array",
+			"minItems": 1,
+			"items": { "$recursiveRef": "#" }
+		}
+	}
+}

validator/src/metaschemas/draft/2019-09/meta/content

@@ -0,0 +1,15 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/meta/content",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/content": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Content vocabulary meta-schema",
+	"type": ["object", "boolean"],
+	"properties": {
+		"contentMediaType": { "type": "string" },
+		"contentEncoding": { "type": "string" },
+		"contentSchema": { "$recursiveRef": "#" }
+	}
+}

validator/src/metaschemas/draft/2019-09/meta/core

@@ -0,0 +1,56 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/meta/core",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/core": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Core vocabulary meta-schema",
+	"type": ["object", "boolean"],
+	"properties": {
+		"$id": {
+			"type": "string",
+			"format": "uri-reference",
+			"$comment": "Non-empty fragments not allowed.",
+			"pattern": "^[^#]*#?$"
+		},
+		"$schema": {
+			"type": "string",
+			"format": "uri"
+		},
+		"$anchor": {
+			"type": "string",
+			"pattern": "^[A-Za-z][-A-Za-z0-9.:_]*$"
+		},
+		"$ref": {
+			"type": "string",
+			"format": "uri-reference"
+		},
+		"$recursiveRef": {
+			"type": "string",
+			"format": "uri-reference"
+		},
+		"$recursiveAnchor": {
+			"type": "boolean",
+			"default": false
+		},
+		"$vocabulary": {
+			"type": "object",
+			"propertyNames": {
+				"type": "string",
+				"format": "uri"
+			},
+			"additionalProperties": {
+				"type": "boolean"
+			}
+		},
+		"$comment": {
+			"type": "string"
+		},
+		"$defs": {
+			"type": "object",
+			"additionalProperties": { "$recursiveRef": "#" },
+			"default": {}
+		}
+	}
+}

validator/src/metaschemas/draft/2019-09/meta/format

@@ -0,0 +1,13 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/meta/format",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/format": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Format vocabulary meta-schema",
+	"type": ["object", "boolean"],
+	"properties": {
+		"format": { "type": "string" }
+	}
+}

validator/src/metaschemas/draft/2019-09/meta/meta-data

@@ -0,0 +1,35 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/meta/meta-data",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/meta-data": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Meta-data vocabulary meta-schema",
+	"type": ["object", "boolean"],
+	"properties": {
+		"title": {
+			"type": "string"
+		},
+		"description": {
+			"type": "string"
+		},
+		"default": true,
+		"deprecated": {
+			"type": "boolean",
+			"default": false
+		},
+		"readOnly": {
+			"type": "boolean",
+			"default": false
+		},
+		"writeOnly": {
+			"type": "boolean",
+			"default": false
+		},
+		"examples": {
+			"type": "array",
+			"items": true
+		}
+	}
+}

validator/src/metaschemas/draft/2019-09/meta/validation

@@ -0,0 +1,97 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/meta/validation",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/validation": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Validation vocabulary meta-schema",
+	"type": ["object", "boolean"],
+	"properties": {
+		"multipleOf": {
+			"type": "number",
+			"exclusiveMinimum": 0
+		},
+		"maximum": {
+			"type": "number"
+		},
+		"exclusiveMaximum": {
+			"type": "number"
+		},
+		"minimum": {
+			"type": "number"
+		},
+		"exclusiveMinimum": {
+			"type": "number"
+		},
+		"maxLength": { "$ref": "#/$defs/nonNegativeInteger" },
+		"minLength": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+		"pattern": {
+			"type": "string",
+			"format": "regex"
+		},
+		"maxItems": { "$ref": "#/$defs/nonNegativeInteger" },
+		"minItems": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+		"uniqueItems": {
+			"type": "boolean",
+			"default": false
+		},
+		"maxContains": { "$ref": "#/$defs/nonNegativeInteger" },
+		"minContains": {
+			"$ref": "#/$defs/nonNegativeInteger",
+			"default": 1
+		},
+		"maxProperties": { "$ref": "#/$defs/nonNegativeInteger" },
+		"minProperties": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+		"required": { "$ref": "#/$defs/stringArray" },
+		"dependentRequired": {
+			"type": "object",
+			"additionalProperties": {
+				"$ref": "#/$defs/stringArray"
+			}
+		},
+		"const": true,
+		"enum": {
+			"type": "array",
+			"items": true
+		},
+		"type": {
+			"anyOf": [
+				{ "$ref": "#/$defs/simpleTypes" },
+				{
+					"type": "array",
+					"items": { "$ref": "#/$defs/simpleTypes" },
+					"minItems": 1,
+					"uniqueItems": true
+				}
+			]
+		}
+	},
+	"$defs": {
+		"nonNegativeInteger": {
+			"type": "integer",
+			"minimum": 0
+		},
+		"nonNegativeIntegerDefault0": {
+			"$ref": "#/$defs/nonNegativeInteger",
+			"default": 0
+		},
+		"simpleTypes": {
+			"enum": [
+				"array",
+				"boolean",
+				"integer",
+				"null",
+				"number",
+				"object",
+				"string"
+			]
+		},
+		"stringArray": {
+			"type": "array",
+			"items": { "type": "string" },
+			"uniqueItems": true,
+			"default": []
+		}
+	}
+}

validator/src/metaschemas/draft/2019-09/schema

@@ -0,0 +1,41 @@
+{
+	"$schema": "https://json-schema.org/draft/2019-09/schema",
+	"$id": "https://json-schema.org/draft/2019-09/schema",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2019-09/vocab/core": true,
+		"https://json-schema.org/draft/2019-09/vocab/applicator": true,
+		"https://json-schema.org/draft/2019-09/vocab/validation": true,
+		"https://json-schema.org/draft/2019-09/vocab/meta-data": true,
+		"https://json-schema.org/draft/2019-09/vocab/format": false,
+		"https://json-schema.org/draft/2019-09/vocab/content": true
+	},
+	"$recursiveAnchor": true,
+	"title": "Core and Validation specifications meta-schema",
+	"allOf": [
+		{"$ref": "meta/core"},
+		{"$ref": "meta/applicator"},
+		{"$ref": "meta/validation"},
+		{"$ref": "meta/meta-data"},
+		{"$ref": "meta/format"},
+		{"$ref": "meta/content"}
+	],
+	"type": ["object", "boolean"],
+	"properties": {
+		"definitions": {
+			"$comment": "While no longer an official keyword as it is replaced by $defs, this keyword is retained in the meta-schema to prevent incompatible extensions as it remains in common use.",
+			"type": "object",
+			"additionalProperties": { "$recursiveRef": "#" },
+			"default": {}
+		},
+		"dependencies": {
+			"$comment": "\"dependencies\" is no longer a keyword, but schema authors should avoid redefining it to facilitate a smooth transition to \"dependentSchemas\" and \"dependentRequired\"",
+			"type": "object",
+			"additionalProperties": {
+				"anyOf": [
+					{ "$recursiveRef": "#" },
+					{ "$ref": "meta/validation#/$defs/stringArray" }
+				]
+			}
+		}
+	}
+}

validator/src/metaschemas/draft/2020-12/meta/applicator

@@ -0,0 +1,47 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/applicator",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/applicator": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Applicator vocabulary meta-schema",
+		"type": ["object", "boolean"],
+		"properties": {
+			"prefixItems": { "$ref": "#/$defs/schemaArray" },
+			"items": { "$dynamicRef": "#meta" },
+			"contains": { "$dynamicRef": "#meta" },
+			"additionalProperties": { "$dynamicRef": "#meta" },
+			"properties": {
+				"type": "object",
+				"additionalProperties": { "$dynamicRef": "#meta" },
+				"default": {}
+			},
+			"patternProperties": {
+				"type": "object",
+				"additionalProperties": { "$dynamicRef": "#meta" },
+				"propertyNames": { "format": "regex" },
+				"default": {}
+			},
+			"dependentSchemas": {
+				"type": "object",
+				"additionalProperties": { "$dynamicRef": "#meta" },
+				"default": {}
+			},
+			"propertyNames": { "$dynamicRef": "#meta" },
+			"if": { "$dynamicRef": "#meta" },
+			"then": { "$dynamicRef": "#meta" },
+			"else": { "$dynamicRef": "#meta" },
+			"allOf": { "$ref": "#/$defs/schemaArray" },
+			"anyOf": { "$ref": "#/$defs/schemaArray" },
+			"oneOf": { "$ref": "#/$defs/schemaArray" },
+			"not": { "$dynamicRef": "#meta" }
+		},
+		"$defs": {
+			"schemaArray": {
+				"type": "array",
+				"minItems": 1,
+				"items": { "$dynamicRef": "#meta" }
+			}
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/content

@@ -0,0 +1,15 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/content",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/content": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Content vocabulary meta-schema",
+		"type": ["object", "boolean"],
+		"properties": {
+			"contentEncoding": { "type": "string" },
+			"contentMediaType": { "type": "string" },
+			"contentSchema": { "$dynamicRef": "#meta" }
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/core

@@ -0,0 +1,50 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/core",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/core": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Core vocabulary meta-schema",
+		"type": ["object", "boolean"],
+		"properties": {
+			"$id": {
+				"$ref": "#/$defs/uriReferenceString",
+				"$comment": "Non-empty fragments not allowed.",
+				"pattern": "^[^#]*#?$"
+			},
+			"$schema": { "$ref": "#/$defs/uriString" },
+			"$ref": { "$ref": "#/$defs/uriReferenceString" },
+			"$anchor": { "$ref": "#/$defs/anchorString" },
+			"$dynamicRef": { "$ref": "#/$defs/uriReferenceString" },
+			"$dynamicAnchor": { "$ref": "#/$defs/anchorString" },
+			"$vocabulary": {
+				"type": "object",
+				"propertyNames": { "$ref": "#/$defs/uriString" },
+				"additionalProperties": {
+					"type": "boolean"
+				}
+			},
+			"$comment": {
+				"type": "string"
+			},
+			"$defs": {
+				"type": "object",
+				"additionalProperties": { "$dynamicRef": "#meta" }
+			}
+		},
+		"$defs": {
+			"anchorString": {
+				"type": "string",
+				"pattern": "^[A-Za-z_][-A-Za-z0-9._]*$"
+			},
+			"uriString": {
+				"type": "string",
+				"format": "uri"
+			},
+			"uriReferenceString": {
+				"type": "string",
+				"format": "uri-reference"
+			}
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/format-annotation

@@ -0,0 +1,13 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/format-annotation",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/format-annotation": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Format vocabulary meta-schema for annotation results",
+		"type": ["object", "boolean"],
+		"properties": {
+			"format": { "type": "string" }
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/format-assertion

@@ -0,0 +1,13 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/format-assertion",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/format-assertion": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Format vocabulary meta-schema for assertion results",
+		"type": ["object", "boolean"],
+		"properties": {
+			"format": { "type": "string" }
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/meta-data

@@ -0,0 +1,35 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/meta-data",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/meta-data": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Meta-data vocabulary meta-schema",
+		"type": ["object", "boolean"],
+		"properties": {
+			"title": {
+				"type": "string"
+			},
+			"description": {
+				"type": "string"
+			},
+			"default": true,
+			"deprecated": {
+				"type": "boolean",
+				"default": false
+			},
+			"readOnly": {
+				"type": "boolean",
+				"default": false
+			},
+			"writeOnly": {
+				"type": "boolean",
+				"default": false
+			},
+			"examples": {
+				"type": "array",
+				"items": true
+			}
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/unevaluated

@@ -0,0 +1,14 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/unevaluated",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/unevaluated": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Unevaluated applicator vocabulary meta-schema",
+		"type": ["object", "boolean"],
+		"properties": {
+			"unevaluatedItems": { "$dynamicRef": "#meta" },
+			"unevaluatedProperties": { "$dynamicRef": "#meta" }
+		}
+}

validator/src/metaschemas/draft/2020-12/meta/validation

@@ -0,0 +1,97 @@
+{
+		"$schema": "https://json-schema.org/draft/2020-12/schema",
+		"$id": "https://json-schema.org/draft/2020-12/meta/validation",
+		"$vocabulary": {
+			"https://json-schema.org/draft/2020-12/vocab/validation": true
+		},
+		"$dynamicAnchor": "meta",
+		"title": "Validation vocabulary meta-schema",
+		"type": ["object", "boolean"],
+		"properties": {
+			"type": {
+				"anyOf": [
+					{ "$ref": "#/$defs/simpleTypes" },
+					{
+						"type": "array",
+						"items": { "$ref": "#/$defs/simpleTypes" },
+						"minItems": 1,
+						"uniqueItems": true
+					}
+				]
+			},
+			"const": true,
+			"enum": {
+				"type": "array",
+				"items": true
+			},
+			"multipleOf": {
+				"type": "number",
+				"exclusiveMinimum": 0
+			},
+			"maximum": {
+				"type": "number"
+			},
+			"exclusiveMaximum": {
+				"type": "number"
+			},
+			"minimum": {
+				"type": "number"
+			},
+			"exclusiveMinimum": {
+				"type": "number"
+			},
+			"maxLength": { "$ref": "#/$defs/nonNegativeInteger" },
+			"minLength": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+			"pattern": {
+				"type": "string",
+				"format": "regex"
+			},
+			"maxItems": { "$ref": "#/$defs/nonNegativeInteger" },
+			"minItems": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+			"uniqueItems": {
+				"type": "boolean",
+				"default": false
+			},
+			"maxContains": { "$ref": "#/$defs/nonNegativeInteger" },
+			"minContains": {
+				"$ref": "#/$defs/nonNegativeInteger",
+				"default": 1
+			},
+			"maxProperties": { "$ref": "#/$defs/nonNegativeInteger" },
+			"minProperties": { "$ref": "#/$defs/nonNegativeIntegerDefault0" },
+			"required": { "$ref": "#/$defs/stringArray" },
+			"dependentRequired": {
+				"type": "object",
+				"additionalProperties": {
+					"$ref": "#/$defs/stringArray"
+				}
+			}
+		},
+		"$defs": {
+			"nonNegativeInteger": {
+				"type": "integer",
+				"minimum": 0
+			},
+			"nonNegativeIntegerDefault0": {
+				"$ref": "#/$defs/nonNegativeInteger",
+				"default": 0
+			},
+			"simpleTypes": {
+				"enum": [
+					"array",
+					"boolean",
+					"integer",
+					"null",
+					"number",
+					"object",
+					"string"
+				]
+			},
+			"stringArray": {
+				"type": "array",
+				"items": { "type": "string" },
+				"uniqueItems": true,
+				"default": []
+			}
+		}
+}

validator/src/metaschemas/draft/2020-12/schema

@@ -0,0 +1,57 @@
+{
+	"$schema": "https://json-schema.org/draft/2020-12/schema",
+	"$id": "https://json-schema.org/draft/2020-12/schema",
+	"$vocabulary": {
+		"https://json-schema.org/draft/2020-12/vocab/core": true,
+		"https://json-schema.org/draft/2020-12/vocab/applicator": true,
+		"https://json-schema.org/draft/2020-12/vocab/unevaluated": true,
+		"https://json-schema.org/draft/2020-12/vocab/validation": true,
+		"https://json-schema.org/draft/2020-12/vocab/meta-data": true,
+		"https://json-schema.org/draft/2020-12/vocab/format-annotation": true,
+		"https://json-schema.org/draft/2020-12/vocab/content": true
+	},
+	"$dynamicAnchor": "meta",
+	"title": "Core and Validation specifications meta-schema",
+	"allOf": [
+		{"$ref": "meta/core"},
+		{"$ref": "meta/applicator"},
+		{"$ref": "meta/unevaluated"},
+		{"$ref": "meta/validation"},
+		{"$ref": "meta/meta-data"},
+		{"$ref": "meta/format-annotation"},
+		{"$ref": "meta/content"}
+	],
+	"type": ["object", "boolean"],
+	"$comment": "This meta-schema also defines keywords that have appeared in previous drafts in order to prevent incompatible extensions as they remain in common use.",
+	"properties": {
+		"definitions": {
+			"$comment": "\"definitions\" has been replaced by \"$defs\".",
+			"type": "object",
+			"additionalProperties": { "$dynamicRef": "#meta" },
+			"deprecated": true,
+			"default": {}
+		},
+		"dependencies": {
+			"$comment": "\"dependencies\" has been split and replaced by \"dependentSchemas\" and \"dependentRequired\" in order to serve their differing semantics.",
+			"type": "object",
+			"additionalProperties": {
+				"anyOf": [
+					{ "$dynamicRef": "#meta" },
+					{ "$ref": "meta/validation#/$defs/stringArray" }
+				]
+			},
+			"deprecated": true,
+			"default": {}
+		},
+		"$recursiveAnchor": {
+			"$comment": "\"$recursiveAnchor\" has been replaced by \"$dynamicAnchor\".",
+			"$ref": "meta/core#/$defs/anchorString",
+			"deprecated": true
+		},
+		"$recursiveRef": {
+			"$comment": "\"$recursiveRef\" has been replaced by \"$dynamicRef\".",
+			"$ref": "meta/core#/$defs/uriReferenceString",
+			"deprecated": true
+		}
+	}
+}

validator/src/output.rs

@@ -0,0 +1,622 @@
+use std::{
+  borrow::Cow,
+  fmt::{Display, Formatter, Write},
+};
+
+use serde::{
+  ser::{SerializeMap, SerializeSeq},
+  Serialize,
+};
+
+use crate::{util::*, ErrorKind, InstanceLocation, ValidationError};
+
+impl<'s> ValidationError<'s, '_> {
+  fn absolute_keyword_location(&self) -> AbsoluteKeywordLocation<'s> {
+    if let ErrorKind::Reference { url, .. } = &self.kind {
+      AbsoluteKeywordLocation {
+        schema_url: url,
+        keyword_path: None,
+      }
+    } else {
+      AbsoluteKeywordLocation {
+        schema_url: self.schema_url,
+        keyword_path: self.kind.keyword_path(),
+      }
+    }
+  }
+
+  fn skip(&self) -> bool {
+    self.causes.len() == 1 && matches!(self.kind, ErrorKind::Reference { .. })
+  }
+
+  /// The `Flag` output format, merely the boolean result.
+  pub fn flag_output(&self) -> FlagOutput {
+    FlagOutput { valid: false }
+  }
+
+  /// The `Basic` structure, a flat list of output units.
+  pub fn basic_output(&self) -> OutputUnit<'_, '_, '_> {
+    let mut outputs = vec![];
+
+    let mut in_ref = InRef::default();
+    let mut kw_loc = KeywordLocation::default();
+    for node in DfsIterator::new(self) {
+      match node {
+        DfsItem::Pre(e) => {
+          in_ref.pre(e);
+          kw_loc.pre(e);
+          if e.skip() || matches!(e.kind, ErrorKind::Schema { .. }) {
+            continue;
+          }
+          let absolute_keyword_location = if in_ref.get() {
+            Some(e.absolute_keyword_location())
+          } else {
+            None
+          };
+          outputs.push(OutputUnit {
+            valid: false,
+            keyword_location: kw_loc.get(e),
+            absolute_keyword_location,
+            instance_location: &e.instance_location,
+            error: OutputError::Leaf(&e.kind),
+          });
+        }
+        DfsItem::Post(e) => {
+          in_ref.post();
+          kw_loc.post();
+          if e.skip() || matches!(e.kind, ErrorKind::Schema { .. }) {
+            continue;
+          }
+        }
+      }
+    }
+
+    let error = if outputs.is_empty() {
+      OutputError::Leaf(&self.kind)
+    } else {
+      OutputError::Branch(outputs)
+    };
+    OutputUnit {
+      valid: false,
+      keyword_location: String::new(),
+      absolute_keyword_location: None,
+      instance_location: &self.instance_location,
+      error,
+    }
+  }
+
+  /// The `Detailed` structure, based on the schema.
+  pub fn detailed_output(&self) -> OutputUnit<'_, '_, '_> {
+    let mut root = None;
+    let mut stack: Vec<OutputUnit> = vec![];
+
+    let mut in_ref = InRef::default();
+    let mut kw_loc = KeywordLocation::default();
+    for node in DfsIterator::new(self) {
+      match node {
+        DfsItem::Pre(e) => {
+          in_ref.pre(e);
+          kw_loc.pre(e);
+          if e.skip() {
+            continue;
+          }
+          let absolute_keyword_location = if in_ref.get() {
+            Some(e.absolute_keyword_location())
+          } else {
+            None
+          };
+          stack.push(OutputUnit {
+            valid: false,
+            keyword_location: kw_loc.get(e),
+            absolute_keyword_location,
+            instance_location: &e.instance_location,
+            error: OutputError::Leaf(&e.kind),
+          });
+        }
+        DfsItem::Post(e) => {
+          in_ref.post();
+          kw_loc.post();
+          if e.skip() {
+            continue;
+          }
+          let output = stack.pop().unwrap();
+          if let Some(parent) = stack.last_mut() {
+            match &mut parent.error {
+              OutputError::Leaf(_) => {
+                parent.error = OutputError::Branch(vec![output]);
+              }
+              OutputError::Branch(v) => v.push(output),
+            }
+          } else {
+            root.replace(output);
+          }
+        }
+      }
+    }
+    root.unwrap()
+  }
+}
+
+// DfsIterator --
+
+impl Display for ValidationError<'_, '_> {
+  /// Formats error hierarchy. Use `#` to show the schema location.
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    let mut indent = Indent::default();
+    let mut sloc = SchemaLocation::default();
+    // let mut kw_loc = KeywordLocation::default();
+    for node in DfsIterator::new(self) {
+      match node {
+        DfsItem::Pre(e) => {
+          // kw_loc.pre(e);
+          if e.skip() {
+            continue;
+          }
+          indent.pre(f)?;
+          if f.alternate() {
+            sloc.pre(e);
+          }
+          if let ErrorKind::Schema { .. } = &e.kind {
+            write!(f, "jsonschema {}", e.kind)?;
+          } else {
+            write!(f, "at {}", quote(&e.instance_location.to_string()))?;
+            if f.alternate() {
+              write!(f, " [{}]", sloc)?;
+              // write!(f, " [{}]", kw_loc.get(e))?;
+              // write!(f, " [{}]", e.absolute_keyword_location())?;
+            }
+            write!(f, ": {}", e.kind)?;
+          }
+        }
+        DfsItem::Post(e) => {
+          // kw_loc.post();
+          if e.skip() {
+            continue;
+          }
+          indent.post();
+          sloc.post();
+        }
+      }
+    }
+    Ok(())
+  }
+}
+
+struct DfsIterator<'a, 'v, 's> {
+  root: Option<&'a ValidationError<'v, 's>>,
+  stack: Vec<Frame<'a, 'v, 's>>,
+}
+
+impl<'a, 'v, 's> DfsIterator<'a, 'v, 's> {
+  fn new(err: &'a ValidationError<'v, 's>) -> Self {
+    DfsIterator {
+      root: Some(err),
+      stack: vec![],
+    }
+  }
+}
+
+impl<'a, 'v, 's> Iterator for DfsIterator<'a, 'v, 's> {
+  type Item = DfsItem<&'a ValidationError<'v, 's>>;
+
+  fn next(&mut self) -> Option<Self::Item> {
+    let Some(mut frame) = self.stack.pop() else {
+      if let Some(err) = self.root.take() {
+        self.stack.push(Frame::from(err));
+        return Some(DfsItem::Pre(err));
+      } else {
+        return None;
+      }
+    };
+
+    if frame.causes.is_empty() {
+      return Some(DfsItem::Post(frame.err));
+    }
+
+    let err = &frame.causes[0];
+    frame.causes = &frame.causes[1..];
+    self.stack.push(frame);
+    self.stack.push(Frame::from(err));
+    Some(DfsItem::Pre(err))
+  }
+}
+
+struct Frame<'a, 'v, 's> {
+  err: &'a ValidationError<'v, 's>,
+  causes: &'a [ValidationError<'v, 's>],
+}
+
+impl<'a, 'v, 's> Frame<'a, 'v, 's> {
+  fn from(err: &'a ValidationError<'v, 's>) -> Self {
+    Self {
+      err,
+      causes: &err.causes,
+    }
+  }
+}
+
+enum DfsItem<T> {
+  Pre(T),
+  Post(T),
+}
+
+// Indent --
+
+#[derive(Default)]
+struct Indent {
+  n: usize,
+}
+
+impl Indent {
+  fn pre(&mut self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+    if self.n > 0 {
+      writeln!(f)?;
+      for _ in 0..self.n - 1 {
+        write!(f, " ")?;
+      }
+      write!(f, "- ")?;
+    }
+    self.n += 1;
+    Ok(())
+  }
+
+  fn post(&mut self) {
+    self.n -= 1;
+  }
+}
+
+// SchemaLocation
+
+#[derive(Default)]
+struct SchemaLocation<'a, 's, 'v> {
+  stack: Vec<&'a ValidationError<'s, 'v>>,
+}
+
+impl<'a, 's, 'v> SchemaLocation<'a, 's, 'v> {
+  fn pre(&mut self, e: &'a ValidationError<'s, 'v>) {
+    self.stack.push(e);
+  }
+
+  fn post(&mut self) {
+    self.stack.pop();
+  }
+}
+
+impl Display for SchemaLocation<'_, '_, '_> {
+  fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+    let mut iter = self.stack.iter().cloned();
+    let cur = iter.next_back().unwrap();
+    let cur: Cow<str> = match &cur.kind {
+      ErrorKind::Schema { url } => Cow::Borrowed(url),
+      ErrorKind::Reference { url, .. } => Cow::Borrowed(url),
+      _ => Cow::Owned(cur.absolute_keyword_location().to_string()),
+    };
+
+    let Some(prev) = iter.next_back() else {
+      return write!(f, "{cur}");
+    };
+
+    let p = match &prev.kind {
+      ErrorKind::Schema { url } => {
+        let (p, _) = split(url);
+        p
+      }
+      ErrorKind::Reference { url, .. } => {
+        let (p, _) = split(url);
+        p
+      }
+      _ => {
+        let (p, _) = split(prev.schema_url);
+        p
+      }
+    };
+    let (c, frag) = split(cur.as_ref());
+    if c == p {
+      write!(f, "S#{frag}")
+    } else {
+      write!(f, "{cur}")
+    }
+  }
+}
+
+// KeywordLocation --
+
+#[derive(Default)]
+struct KeywordLocation<'a> {
+  loc: String,
+  stack: Vec<(&'a str, usize)>, // (schema_url, len)
+}
+
+impl<'a> KeywordLocation<'a> {
+  fn pre(&mut self, e: &'a ValidationError) {
+    let cur = match &e.kind {
+      ErrorKind::Schema { url } => url,
+      ErrorKind::Reference { url, .. } => url,
+      _ => e.schema_url,
+    };
+
+    if let Some((prev, _)) = self.stack.last() {
+      self.loc.push_str(&e.schema_url[prev.len()..]); // todo: url-decode
+      if let ErrorKind::Reference { kw, .. } = &e.kind {
+        self.loc.push('/');
+        self.loc.push_str(kw);
+      }
+    }
+    self.stack.push((cur, self.loc.len()));
+  }
+
+  fn post(&mut self) {
+    self.stack.pop();
+    if let Some((_, len)) = self.stack.last() {
+      self.loc.truncate(*len);
+    }
+  }
+
+  fn get(&mut self, cur: &'a ValidationError) -> String {
+    if let ErrorKind::Reference { .. } = &cur.kind {
+      self.loc.clone()
+    } else if let Some(kw_path) = &cur.kind.keyword_path() {
+      let len = self.loc.len();
+      self.loc.push('/');
+      write!(self.loc, "{}", kw_path).expect("write kw_path to String should not fail");
+      let loc = self.loc.clone();
+      self.loc.truncate(len);
+      loc
+    } else {
+      self.loc.clone()
+    }
+  }
+}
+
+#[derive(Default)]
+struct InRef {
+  stack: Vec<bool>,
+}
+
+impl InRef {
+  fn pre(&mut self, e: &ValidationError) {
+    let in_ref: bool = self.get() || matches!(e.kind, ErrorKind::Reference { .. });
+    self.stack.push(in_ref);
+  }
+
+  fn post(&mut self) {
+    self.stack.pop();
+  }
+
+  fn get(&self) -> bool {
+    self.stack.last().cloned().unwrap_or_default()
+  }
+}
+
+// output formats --
+
+/// Simplest output format, merely the boolean result.
+pub struct FlagOutput {
+  pub valid: bool,
+}
+
+impl Serialize for FlagOutput {
+  fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+  where
+    S: serde::Serializer,
+  {
+    let mut map = serializer.serialize_map(Some(1))?;
+    map.serialize_entry("valid", &self.valid)?;
+    map.end()
+  }
+}
+
+impl Display for FlagOutput {
+  fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+    write_json_to_fmt(f, self)
+  }
+}
+
+/// Single OutputUnit used in Basic/Detailed output formats.
+pub struct OutputUnit<'e, 's, 'v> {
+  pub valid: bool,
+  pub keyword_location: String,
+  /// The absolute, dereferenced location of the validating keyword
+  pub absolute_keyword_location: Option<AbsoluteKeywordLocation<'s>>,
+  /// The location of the JSON value within the instance being validated
+  pub instance_location: &'e InstanceLocation<'v>,
+  pub error: OutputError<'e, 's, 'v>,
+}
+
+impl Serialize for OutputUnit<'_, '_, '_> {
+  fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+  where
+    S: serde::Serializer,
+  {
+    let n = 4 + self.absolute_keyword_location.as_ref().map_or(0, |_| 1);
+    let mut map = serializer.serialize_map(Some(n))?;
+    map.serialize_entry("valid", &self.valid)?;
+    map.serialize_entry("keywordLocation", &self.keyword_location.to_string())?;
+    if let Some(s) = &self.absolute_keyword_location {
+      map.serialize_entry("absoluteKeywordLocation", &s.to_string())?;
+    }
+    map.serialize_entry("instanceLocation", &self.instance_location.to_string())?;
+    let pname = match self.error {
+      OutputError::Leaf(_) => "error",
+      OutputError::Branch(_) => "errors",
+    };
+    map.serialize_entry(pname, &self.error)?;
+    map.end()
+  }
+}
+
+impl Display for OutputUnit<'_, '_, '_> {
+  fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+    write_json_to_fmt(f, self)
+  }
+}
+
+/// Error of [`OutputUnit`].
+pub enum OutputError<'e, 's, 'v> {
+  /// Single.
+  Leaf(&'e ErrorKind<'s, 'v>),
+  /// Nested.
+  Branch(Vec<OutputUnit<'e, 's, 'v>>),
+}
+
+impl Serialize for OutputError<'_, '_, '_> {
+  fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+  where
+    S: serde::Serializer,
+  {
+    match self {
+      OutputError::Leaf(kind) => serializer.serialize_str(&kind.to_string()),
+      OutputError::Branch(units) => {
+        let mut seq = serializer.serialize_seq(Some(units.len()))?;
+        for unit in units {
+          seq.serialize_element(unit)?;
+        }
+        seq.end()
+      }
+    }
+  }
+}
+
+// AbsoluteKeywordLocation --
+
+impl<'s> ErrorKind<'s, '_> {
+  pub fn keyword_path(&self) -> Option<KeywordPath<'s>> {
+    #[inline(always)]
+    fn kw(kw: &'static str) -> Option<KeywordPath<'static>> {
+      Some(KeywordPath {
+        keyword: kw,
+        token: None,
+      })
+    }
+
+    #[inline(always)]
+    fn kw_prop<'s>(kw: &'static str, prop: &'s str) -> Option<KeywordPath<'s>> {
+      Some(KeywordPath {
+        keyword: kw,
+        token: Some(SchemaToken::Prop(prop)),
+      })
+    }
+
+    use ErrorKind::*;
+    match self {
+      Group => None,
+      Schema { .. } => None,
+      ContentSchema => kw("contentSchema"),
+      PropertyName { .. } => kw("propertyNames"),
+      Reference { kw: kword, .. } => kw(kword),
+      RefCycle { .. } => None,
+      FalseSchema => None,
+      Type { .. } => kw("type"),
+      Enum { .. } => kw("enum"),
+      Const { .. } => kw("const"),
+      Format { .. } => kw("format"),
+      MinProperties { .. } => kw("minProperties"),
+      MaxProperties { .. } => kw("maxProperties"),
+      AdditionalProperties { .. } => kw("additionalProperty"),
+      Required { .. } => kw("required"),
+      Dependency { prop, .. } => kw_prop("dependencies", prop),
+      DependentRequired { prop, .. } => kw_prop("dependentRequired", prop),
+      MinItems { .. } => kw("minItems"),
+      MaxItems { .. } => kw("maxItems"),
+      Contains => kw("contains"),
+      MinContains { .. } => kw("minContains"),
+      MaxContains { .. } => kw("maxContains"),
+      UniqueItems { .. } => kw("uniqueItems"),
+      AdditionalItems { .. } => kw("additionalItems"),
+      MinLength { .. } => kw("minLength"),
+      MaxLength { .. } => kw("maxLength"),
+      Pattern { .. } => kw("pattern"),
+      ContentEncoding { .. } => kw("contentEncoding"),
+      ContentMediaType { .. } => kw("contentMediaType"),
+      Minimum { .. } => kw("minimum"),
+      Maximum { .. } => kw("maximum"),
+      ExclusiveMinimum { .. } => kw("exclusiveMinimum"),
+      ExclusiveMaximum { .. } => kw("exclusiveMaximum"),
+      MultipleOf { .. } => kw("multipleOf"),
+      Not => kw("not"),
+      AllOf => kw("allOf"),
+      AnyOf => kw("anyOf"),
+      OneOf(_) => kw("oneOf"),
+    }
+  }
+}
+
+/// The absolute, dereferenced location of the validating keyword
+#[derive(Debug, Clone)]
+pub struct AbsoluteKeywordLocation<'s> {
+  /// The absolute, dereferenced schema location.
+  pub schema_url: &'s str,
+  /// Location within the `schema_url`.
+  pub keyword_path: Option<KeywordPath<'s>>,
+}
+
+impl Display for AbsoluteKeywordLocation<'_> {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    self.schema_url.fmt(f)?;
+    if let Some(path) = &self.keyword_path {
+      f.write_str("/")?;
+      path.keyword.fmt(f)?;
+      if let Some(token) = &path.token {
+        f.write_str("/")?;
+        match token {
+          SchemaToken::Prop(p) => write!(f, "{}", escape(p))?, // todo: url-encode
+          SchemaToken::Item(i) => write!(f, "{i}")?,
+        }
+      }
+    }
+    Ok(())
+  }
+}
+
+#[derive(Debug, Clone)]
+/// JsonPointer in schema.
+pub struct KeywordPath<'s> {
+  /// The first token.
+  pub keyword: &'static str,
+  /// Optinal token within keyword.
+  pub token: Option<SchemaToken<'s>>,
+}
+
+impl Display for KeywordPath<'_> {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    self.keyword.fmt(f)?;
+    if let Some(token) = &self.token {
+      f.write_str("/")?;
+      token.fmt(f)?;
+    }
+    Ok(())
+  }
+}
+
+/// Token for schema.
+#[derive(Debug, Clone)]
+pub enum SchemaToken<'s> {
+  /// Token for property.
+  Prop(&'s str),
+  /// Token for array item.
+  Item(usize),
+}
+
+impl Display for SchemaToken<'_> {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    match self {
+      SchemaToken::Prop(p) => write!(f, "{}", escape(p)),
+      SchemaToken::Item(i) => write!(f, "{i}"),
+    }
+  }
+}
+
+// helpers --
+
+fn write_json_to_fmt<T>(f: &mut std::fmt::Formatter, value: &T) -> Result<(), std::fmt::Error>
+where
+  T: ?Sized + Serialize,
+{
+  let s = if f.alternate() {
+    serde_json::to_string_pretty(value)
+  } else {
+    serde_json::to_string(value)
+  };
+  let s = s.map_err(|_| std::fmt::Error)?;
+  f.write_str(&s)
+}

validator/src/root.rs

@@ -0,0 +1,128 @@
+use std::collections::{HashMap, HashSet};
+
+use crate::{compiler::CompileError, draft::*, util::*};
+
+use serde_json::Value;
+use url::Url;
+
+pub(crate) struct Root {
+  pub(crate) draft: &'static Draft,
+  pub(crate) resources: HashMap<JsonPointer, Resource>, // ptr => _
+  pub(crate) url: Url,
+  pub(crate) meta_vocabs: Option<Vec<String>>,
+}
+
+impl Root {
+  pub(crate) fn has_vocab(&self, name: &str) -> bool {
+    if self.draft.version < 2019 || name == "core" {
+      return true;
+    }
+    if let Some(vocabs) = &self.meta_vocabs {
+      return vocabs.iter().any(|s| s == name);
+    }
+    self.draft.default_vocabs.contains(&name)
+  }
+
+  fn resolve_fragment_in(&self, frag: &Fragment, res: &Resource) -> Result<UrlPtr, CompileError> {
+    let ptr = match frag {
+      Fragment::Anchor(anchor) => {
+        let Some(ptr) = res.anchors.get(anchor) else {
+          return Err(CompileError::AnchorNotFound {
+            url: self.url.to_string(),
+            reference: UrlFrag::format(&res.id, frag.as_str()),
+          });
+        };
+        ptr.clone()
+      }
+      Fragment::JsonPointer(ptr) => res.ptr.concat(ptr),
+    };
+    Ok(UrlPtr {
+      url: self.url.clone(),
+      ptr,
+    })
+  }
+
+  pub(crate) fn resolve_fragment(&self, frag: &Fragment) -> Result<UrlPtr, CompileError> {
+    let res = self.resources.get("").ok_or(CompileError::Bug(
+      format!("no root resource found for {}", self.url).into(),
+    ))?;
+    self.resolve_fragment_in(frag, res)
+  }
+
+  // resolves `UrlFrag` to `UrlPtr` from root.
+  // returns `None` if it is external.
+  pub(crate) fn resolve(&self, uf: &UrlFrag) -> Result<Option<UrlPtr>, CompileError> {
+    let res = {
+      if uf.url == self.url {
+        self.resources.get("").ok_or(CompileError::Bug(
+          format!("no root resource found for {}", self.url).into(),
+        ))?
+      } else {
+        // look for resource with id==uf.url
+        let Some(res) = self.resources.values().find(|res| res.id == uf.url) else {
+          return Ok(None); // external url
+        };
+        res
+      }
+    };
+
+    self.resolve_fragment_in(&uf.frag, res).map(Some)
+  }
+
+  pub(crate) fn resource(&self, ptr: &JsonPointer) -> &Resource {
+    let mut ptr = ptr.as_str();
+    loop {
+      if let Some(res) = self.resources.get(ptr) {
+        return res;
+      }
+      let Some((prefix, _)) = ptr.rsplit_once('/') else {
+        break;
+      };
+      ptr = prefix;
+    }
+    self.resources.get("").expect("root resource should exist")
+  }
+
+  pub(crate) fn base_url(&self, ptr: &JsonPointer) -> &Url {
+    &self.resource(ptr).id
+  }
+
+  pub(crate) fn add_subschema(
+    &mut self,
+    doc: &Value,
+    ptr: &JsonPointer,
+  ) -> Result<(), CompileError> {
+    let v = ptr.lookup(doc, &self.url)?;
+    let base_url = self.base_url(ptr).clone();
+    self.draft
+      .collect_resources(v, &base_url, ptr.clone(), &self.url, &mut self.resources)?;
+
+    // collect anchors
+    if !self.resources.contains_key(ptr) {
+      let res = self.resource(ptr);
+      if let Some(res) = self.resources.get_mut(&res.ptr.clone()) {
+        self.draft.collect_anchors(v, ptr, res, &self.url)?;
+      }
+    }
+    Ok(())
+  }
+}
+
+#[derive(Debug)]
+pub(crate) struct Resource {
+  pub(crate) ptr: JsonPointer, // from root
+  pub(crate) id: Url,
+  pub(crate) anchors: HashMap<Anchor, JsonPointer>, // anchor => ptr
+  pub(crate) dynamic_anchors: HashSet<Anchor>,
+}
+
+impl Resource {
+  pub(crate) fn new(ptr: JsonPointer, id: Url) -> Self {
+    Self {
+      ptr,
+      id,
+      anchors: HashMap::new(),
+      dynamic_anchors: HashSet::new(),
+    }
+  }
+}

validator/src/roots.rs

@@ -0,0 +1,107 @@
+use std::collections::{HashMap, HashSet};
+
+use crate::{compiler::CompileError, draft::*, loader::DefaultUrlLoader, root::Root, util::*};
+
+use serde_json::Value;
+use url::Url;
+
+// --
+
+pub(crate) struct Roots {
+  pub(crate) default_draft: &'static Draft,
+  map: HashMap<Url, Root>,
+  pub(crate) loader: DefaultUrlLoader,
+}
+
+impl Roots {
+  fn new() -> Self {
+    Self {
+      default_draft: latest(),
+      map: Default::default(),
+      loader: DefaultUrlLoader::new(),
+    }
+  }
+}
+
+impl Default for Roots {
+  fn default() -> Self {
+    Self::new()
+  }
+}
+
+impl Roots {
+  pub(crate) fn get(&self, url: &Url) -> Option<&Root> {
+    self.map.get(url)
+  }
+
+  pub(crate) fn resolve_fragment(&mut self, uf: UrlFrag) -> Result<UrlPtr, CompileError> {
+    self.or_load(uf.url.clone())?;
+    let Some(root) = self.map.get(&uf.url) else {
+      return Err(CompileError::Bug("or_load didn't add".into()));
+    };
+    root.resolve_fragment(&uf.frag)
+  }
+
+  pub(crate) fn ensure_subschema(&mut self, up: &UrlPtr) -> Result<(), CompileError> {
+    self.or_load(up.url.clone())?;
+    let Some(root) = self.map.get_mut(&up.url) else {
+      return Err(CompileError::Bug("or_load didn't add".into()));
+    };
+    if !root.draft.is_subschema(up.ptr.as_str()) {
+      let doc = self.loader.load(&root.url)?;
+      let v = up.ptr.lookup(doc, &up.url)?;
+      root.draft.validate(up, v)?;
+      root.add_subschema(doc, &up.ptr)?;
+    }
+    Ok(())
+  }
+
+  pub(crate) fn or_load(&mut self, url: Url) -> Result<(), CompileError> {
+    debug_assert!(url.fragment().is_none(), "trying to add root with fragment");
+    if self.map.contains_key(&url) {
+      return Ok(());
+    }
+    let doc = self.loader.load(&url)?;
+    let r = self.create_root(url.clone(), doc)?;
+    self.map.insert(url, r);
+    Ok(())
+  }
+
+  pub(crate) fn create_root(&self, url: Url, doc: &Value) -> Result<Root, CompileError> {
+    let draft = {
+      let up = UrlPtr {
+        url: url.clone(),
+        ptr: "".into(),
+      };
+      self.loader
+        .get_draft(&up, doc, self.default_draft, HashSet::new())?
+    };
+    let vocabs = self.loader.get_meta_vocabs(doc, draft)?;
+    let resources = {
+      let mut m = HashMap::default();
+      draft.collect_resources(doc, &url, "".into(), &url, &mut m)?;
+      m
+    };
+
+    if !matches!(url.host_str(), Some("json-schema.org")) {
+      draft.validate(
+        &UrlPtr {
+          url: url.clone(),
+          ptr: "".into(),
+        },
+        doc,
+      )?;
+    }
+
+    Ok(Root {
+      draft,
+      resources,
+      url: url.clone(),
+      meta_vocabs: vocabs,
+    })
+  }
+
+  pub(crate) fn insert(&mut self, roots: &mut HashMap<Url, Root>) {
+    self.map.extend(roots.drain());
+  }
+}

validator/src/util.rs

@@ -0,0 +1,545 @@
+use std::{
+  borrow::{Borrow, Cow},
+  fmt::Display,
+  hash::{Hash, Hasher},
+  str::FromStr,
+};
+
+use ahash::{AHashMap, AHasher};
+use percent_encoding::{percent_decode_str, AsciiSet, CONTROLS};
+use serde_json::Value;
+use url::Url;
+
+use crate::CompileError;
+
+// --
+
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub(crate) struct JsonPointer(pub(crate) String);
+
+impl JsonPointer {
+pub(crate) fn escape(token: &str) -> Cow<'_, str> {
+    const SPECIAL: [char; 2] = ['~', '/'];
+    if token.contains(SPECIAL) {
+      token.replace('~', "~0").replace('/', "~1").into()
+    } else {
+      token.into()
+    }
+  }
+
+  pub(crate) fn unescape(mut tok: &str) -> Result<Cow<'_, str>, ()> {
+    let Some(mut tilde) = tok.find('~') else {
+      return Ok(Cow::Borrowed(tok));
+    };
+    let mut s = String::with_capacity(tok.len());
+    loop {
+      s.push_str(&tok[..tilde]);
+      tok = &tok[tilde + 1..];
+      match tok.chars().next() {
+        Some('1') => s.push('/'),
+        Some('0') => s.push('~'),
+        _ => return Err(()),
+      }
+      tok = &tok[1..];
+      let Some(i) = tok.find('~') else {
+        s.push_str(tok);
+        break;
+      };
+      tilde = i;
+    }
+    Ok(Cow::Owned(s))
+  }
+
+  pub(crate) fn lookup<'a>(
+    &self,
+    mut v: &'a Value,
+    v_url: &Url,
+  ) -> Result<&'a Value, CompileError> {
+    for tok in self.0.split('/').skip(1) {
+      let Ok(tok) = Self::unescape(tok) else {
+        let loc = UrlFrag::format(v_url, self.as_str());
+        return Err(CompileError::InvalidJsonPointer(loc));
+      };
+      match v {
+        Value::Object(obj) => {
+          if let Some(pvalue) = obj.get(tok.as_ref()) {
+            v = pvalue;
+            continue;
+          }
+        }
+        Value::Array(arr) => {
+          if let Ok(i) = usize::from_str(tok.as_ref()) {
+            if let Some(item) = arr.get(i) {
+              v = item;
+              continue;
+            }
+          };
+        }
+        _ => {}
+      }
+      let loc = UrlFrag::format(v_url, self.as_str());
+      return Err(CompileError::JsonPointerNotFound(loc));
+    }
+    Ok(v)
+  }
+
+  pub(crate) fn as_str(&self) -> &str {
+    &self.0
+  }
+
+  pub(crate) fn is_empty(&self) -> bool {
+    self.0.is_empty()
+  }
+
+  pub(crate) fn concat(&self, next: &Self) -> Self {
+    JsonPointer(format!("{}{}", self.0, next.0))
+  }
+
+  pub(crate) fn append(&self, tok: &str) -> Self {
+    Self(format!("{}/{}", self, Self::escape(tok)))
+  }
+
+  pub(crate) fn append2(&self, tok1: &str, tok2: &str) -> Self {
+    Self(format!(
+      "{}/{}/{}",
+      self,
+      Self::escape(tok1),
+      Self::escape(tok2)
+    ))
+  }
+}
+
+impl Display for JsonPointer {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    self.0.fmt(f)
+  }
+}
+
+impl Borrow<str> for JsonPointer {
+  fn borrow(&self) -> &str {
+    &self.0
+  }
+}
+
+impl From<&str> for JsonPointer {
+  fn from(value: &str) -> Self {
+    Self(value.into())
+  }
+}
+
+// --
+
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub(crate) struct Anchor(pub(crate) String);
+
+impl Display for Anchor {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    self.0.fmt(f)
+  }
+}
+
+impl Borrow<str> for Anchor {
+  fn borrow(&self) -> &str {
+    &self.0
+  }
+}
+
+impl From<&str> for Anchor {
+  fn from(value: &str) -> Self {
+    Self(value.into())
+  }
+}
+
+// --
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub(crate) enum Fragment {
+  Anchor(Anchor),
+  JsonPointer(JsonPointer),
+}
+
+impl Fragment {
+  pub(crate) fn split(s: &str) -> Result<(&str, Fragment), CompileError> {
+    let (u, frag) = split(s);
+    let frag = percent_decode_str(frag)
+      .decode_utf8()
+      .map_err(|src| CompileError::ParseUrlError {
+        url: s.to_string(),
+        src: src.into(),
+      })?
+      .to_string();
+    let frag = if frag.is_empty() || frag.starts_with('/') {
+      Fragment::JsonPointer(JsonPointer(frag))
+    } else {
+      Fragment::Anchor(Anchor(frag))
+    };
+    Ok((u, frag))
+  }
+
+  pub(crate) fn encode(frag: &str) -> String {
+    // https://url.spec.whatwg.org/#fragment-percent-encode-set
+    const FRAGMENT: &AsciiSet = &CONTROLS
+      .add(b'%')
+      .add(b' ')
+      .add(b'"')
+      .add(b'<')
+      .add(b'>')
+      .add(b'`');
+    percent_encoding::utf8_percent_encode(frag, FRAGMENT).to_string()
+  }
+
+  pub(crate) fn as_str(&self) -> &str {
+    match self {
+      Fragment::Anchor(s) => &s.0,
+      Fragment::JsonPointer(s) => &s.0,
+    }
+  }
+}
+
+// --
+
+#[derive(Clone)]
+pub(crate) struct UrlFrag {
+  pub(crate) url: Url,
+  pub(crate) frag: Fragment,
+}
+
+impl UrlFrag {
+  pub(crate) fn absolute(input: &str) -> Result<UrlFrag, CompileError> {
+    let (u, frag) = Fragment::split(input)?;
+
+    // note: windows drive letter is treated as url scheme by url parser
+    #[cfg(not(target_arch = "wasm32"))]
+    if std::env::consts::OS == "windows" && starts_with_windows_drive(u) {
+      let url = Url::from_file_path(u)
+        .map_err(|_| CompileError::Bug(format!("failed to convert {u} into url").into()))?;
+      return Ok(UrlFrag { url, frag });
+    }
+
+    match Url::parse(u) {
+      Ok(url) => Ok(UrlFrag { url, frag }),
+      #[cfg(not(target_arch = "wasm32"))]
+      Err(url::ParseError::RelativeUrlWithoutBase) => {
+        let p = std::path::absolute(u).map_err(|e| CompileError::ParseUrlError {
+          url: u.to_owned(),
+          src: e.into(),
+        })?;
+        let url = Url::from_file_path(p).map_err(|_| {
+          CompileError::Bug(format!("failed to convert {u} into url").into())
+        })?;
+        Ok(UrlFrag { url, frag })
+      }
+      Err(e) => Err(CompileError::ParseUrlError {
+        url: u.to_owned(),
+        src: e.into(),
+      }),
+    }
+  }
+
+  pub(crate) fn join(url: &Url, input: &str) -> Result<UrlFrag, CompileError> {
+    let (input, frag) = Fragment::split(input)?;
+    if input.is_empty() {
+      return Ok(UrlFrag {
+        url: url.clone(),
+        frag,
+      });
+    }
+    let url = url.join(input).map_err(|e| CompileError::ParseUrlError {
+      url: input.to_string(),
+      src: e.into(),
+    })?;
+
+    Ok(UrlFrag { url, frag })
+  }
+
+  pub(crate) fn format(url: &Url, frag: &str) -> String {
+    if frag.is_empty() {
+      url.to_string()
+    } else {
+      format!("{}#{}", url, Fragment::encode(frag))
+    }
+  }
+}
+
+impl Display for UrlFrag {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    write!(f, "{}#{}", self.url, Fragment::encode(self.frag.as_str()))
+  }
+}
+
+// --
+
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub(crate) struct UrlPtr {
+  pub(crate) url: Url,
+  pub(crate) ptr: JsonPointer,
+}
+
+impl UrlPtr {
+  pub(crate) fn lookup<'a>(&self, doc: &'a Value) -> Result<&'a Value, CompileError> {
+    self.ptr.lookup(doc, &self.url)
+  }
+
+  pub(crate) fn format(&self, tok: &str) -> String {
+    format!(
+      "{}#{}/{}",
+      self.url,
+      Fragment::encode(self.ptr.as_str()),
+      Fragment::encode(JsonPointer::escape(tok).as_ref()),
+    )
+  }
+}
+
+impl Display for UrlPtr {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    write!(f, "{}#{}", self.url, Fragment::encode(self.ptr.as_str()))
+  }
+}
+
+// --
+
+pub(crate) fn is_integer(v: &Value) -> bool {
+  match v {
+    Value::Number(n) => {
+      n.is_i64() || n.is_u64() || n.as_f64().filter(|n| n.fract() == 0.0).is_some()
+    }
+    _ => false,
+  }
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+fn starts_with_windows_drive(p: &str) -> bool {
+  p.chars().next().filter(char::is_ascii_uppercase).is_some() && p[1..].starts_with(":\\")
+}
+
+/// returns single-quoted string
+pub(crate) fn quote<T>(s: &T) -> String
+where
+  T: AsRef<str> + std::fmt::Debug + ?Sized,
+{
+  let s = format!("{s:?}").replace(r#"\""#, "\"").replace('\'', r"\'");
+  format!("'{}'", &s[1..s.len() - 1])
+}
+
+pub(crate) fn join_iter<T>(iterable: T, sep: &str) -> String
+where
+  T: IntoIterator,
+  T::Item: Display,
+{
+  iterable
+    .into_iter()
+    .map(|e| e.to_string())
+    .collect::<Vec<_>>()
+    .join(sep)
+}
+
+pub(crate) fn escape(token: &str) -> Cow<'_, str> {
+  JsonPointer::escape(token)
+}
+
+pub(crate) fn split(url: &str) -> (&str, &str) {
+  if let Some(i) = url.find('#') {
+    (&url[..i], &url[i + 1..])
+  } else {
+    (url, "")
+  }
+}
+
+/// serde_json treats 0 and 0.0 not equal. so we cannot simply use v1==v2
+pub(crate) fn equals(v1: &Value, v2: &Value) -> bool {
+  match (v1, v2) {
+    (Value::Null, Value::Null) => true,
+    (Value::Bool(b1), Value::Bool(b2)) => b1 == b2,
+    (Value::Number(n1), Value::Number(n2)) => {
+      if let (Some(n1), Some(n2)) = (n1.as_u64(), n2.as_u64()) {
+        return n1 == n2;
+      }
+      if let (Some(n1), Some(n2)) = (n1.as_i64(), n2.as_i64()) {
+        return n1 == n2;
+      }
+      if let (Some(n1), Some(n2)) = (n1.as_f64(), n2.as_f64()) {
+        return n1 == n2;
+      }
+      false
+    }
+    (Value::String(s1), Value::String(s2)) => s1 == s2,
+    (Value::Array(arr1), Value::Array(arr2)) => {
+      if arr1.len() != arr2.len() {
+        return false;
+      }
+      arr1.iter().zip(arr2).all(|(e1, e2)| equals(e1, e2))
+    }
+    (Value::Object(obj1), Value::Object(obj2)) => {
+      if obj1.len() != obj2.len() {
+        return false;
+      }
+      for (k1, v1) in obj1 {
+        if let Some(v2) = obj2.get(k1) {
+          if !equals(v1, v2) {
+            return false;
+          }
+        } else {
+          return false;
+        }
+      }
+      true
+    }
+    _ => false,
+  }
+}
+
+pub(crate) fn duplicates(arr: &Vec<Value>) -> Option<(usize, usize)> {
+  match arr.as_slice() {
+    [e0, e1] => {
+      if equals(e0, e1) {
+        return Some((0, 1));
+      }
+    }
+    [e0, e1, e2] => {
+      if equals(e0, e1) {
+        return Some((0, 1));
+      } else if equals(e0, e2) {
+        return Some((0, 2));
+      } else if equals(e1, e2) {
+        return Some((1, 2));
+      }
+    }
+    _ => {
+      let len = arr.len();
+      if len <= 20 {
+        for i in 0..len - 1 {
+          for j in i + 1..len {
+            if equals(&arr[i], &arr[j]) {
+              return Some((i, j));
+            }
+          }
+        }
+      } else {
+        let mut seen = AHashMap::with_capacity(len);
+        for (i, item) in arr.iter().enumerate() {
+          if let Some(j) = seen.insert(HashedValue(item), i) {
+            return Some((j, i));
+          }
+        }
+      }
+    }
+  }
+  None
+}
+
+// HashedValue --
+
+// Based on implementation proposed by Sven Marnach:
+// https://stackoverflow.com/questions/60882381/what-is-the-fastest-correct-way-to-detect-that-there-are-no-duplicates-in-a-json
+pub(crate) struct HashedValue<'a>(pub(crate) &'a Value);
+
+impl PartialEq for HashedValue<'_> {
+  fn eq(&self, other: &Self) -> bool {
+    equals(self.0, other.0)
+  }
+}
+
+impl Eq for HashedValue<'_> {}
+
+impl Hash for HashedValue<'_> {
+  fn hash<H: Hasher>(&self, state: &mut H) {
+    match self.0 {
+      Value::Null => state.write_u32(3_221_225_473), // chosen randomly
+      Value::Bool(ref b) => b.hash(state),
+      Value::Number(ref num) => {
+        if let Some(num) = num.as_f64() {
+          num.to_bits().hash(state);
+        } else if let Some(num) = num.as_u64() {
+          num.hash(state);
+        } else if let Some(num) = num.as_i64() {
+          num.hash(state);
+        }
+      }
+      Value::String(ref str) => str.hash(state),
+      Value::Array(ref arr) => {
+        for item in arr {
+          HashedValue(item).hash(state);
+        }
+      }
+      Value::Object(ref obj) => {
+        let mut hash = 0;
+        for (pname, pvalue) in obj {
+          // We have no way of building a new hasher of type `H`, so we
+          // hardcode using the default hasher of a hash map.
+          let mut hasher = AHasher::default();
+          pname.hash(&mut hasher);
+          HashedValue(pvalue).hash(&mut hasher);
+          hash ^= hasher.finish();
+        }
+        state.write_u64(hash);
+      }
+    }
+  }
+}
+
+#[cfg(test)]
+mod tests {
+
+  use ahash::AHashMap;
+  use serde_json::json;
+
+  use super::*;
+
+  #[test]
+  fn test_quote() {
+    assert_eq!(quote(r#"abc"def'ghi"#), r#"'abc"def\'ghi'"#);
+  }
+
+  #[test]
+  fn test_fragment_split() {
+    let tests = [
+      ("#", Fragment::JsonPointer("".into())),
+      ("#/a/b", Fragment::JsonPointer("/a/b".into())),
+      ("#abcd", Fragment::Anchor("abcd".into())),
+      ("#%61%62%63%64", Fragment::Anchor("abcd".into())),
+      (
+        "#%2F%61%62%63%64%2fef",
+        Fragment::JsonPointer("/abcd/ef".into()),
+      ), // '/' is encoded
+      ("#abcd+ef", Fragment::Anchor("abcd+ef".into())), // '+' should not traslate to space
+    ];
+    for test in tests {
+      let (_, got) = Fragment::split(test.0).unwrap();
+      assert_eq!(got, test.1, "Fragment::split({:?})", test.0);
+    }
+  }
+
+  #[test]
+  fn test_unescape() {
+    let tests = [
+      ("bar~0", Some("bar~")),
+      ("bar~1", Some("bar/")),
+      ("bar~01", Some("bar~1")),
+      ("bar~", None),
+      ("bar~~", None),
+    ];
+    for (tok, want) in tests {
+      let res = JsonPointer::unescape(tok).ok();
+      let got = res.as_ref().map(|c| c.as_ref());
+      assert_eq!(got, want, "unescape({:?})", tok)
+    }
+  }
+
+  #[test]
+  fn test_equals() {
+    let tests = [["1.0", "1"], ["-1.0", "-1"]];
+    for [a, b] in tests {
+      let a = serde_json::from_str(a).unwrap();
+      let b = serde_json::from_str(b).unwrap();
+      assert!(equals(&a, &b));
+    }
+  }
+
+  #[test]
+  fn test_hashed_value() {
+    let mut seen = AHashMap::with_capacity(10);
+    let (v1, v2) = (json!(2), json!(2.0));
+    assert!(equals(&v1, &v2));
+    assert!(seen.insert(HashedValue(&v1), 1).is_none());
+    assert!(seen.insert(HashedValue(&v2), 1).is_some());
+  }
+}

validator/tests/Extra-Test-Suite/tests/draft2020-12/const.json

@@ -0,0 +1,21 @@
+[
+    {
+        "description": "zero fraction",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "const": 2
+        },
+        "tests": [
+            {
+                "description": "with fraction",
+                "data": 2.0,
+                "valid": true
+            },
+            {
+                "description": "without fraction",
+                "data": 2,
+                "valid": true
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/infinite-loop-detection.json

@@ -0,0 +1,26 @@
+[
+    {
+        "description": "guard against infinite recursion",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "alice": {
+                    "$anchor": "alice",
+                    "allOf": [{"$ref": "#bob"}]
+                },
+                "bob": {
+                    "$anchor": "bob",
+                    "allOf": [{"$ref": "#alice"}]
+                }
+            },
+            "$ref": "#alice"
+        },
+        "tests": [
+            {
+                "description": "infinite recursion detected",
+                "data": {},
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/optional/contentSchema.json

@@ -0,0 +1,143 @@
+[
+    {
+        "description": "validation of binary-encoded media type documents with schema",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "contentMediaType": "application/json",
+            "contentEncoding": "base64",
+            "contentSchema": { "required": ["foo"], "properties": { "foo": { "type": "string" } } }
+        },
+        "tests": [
+            {
+                "description": "a valid base64-encoded JSON document",
+                "data": "eyJmb28iOiAiYmFyIn0K",
+                "valid": true
+            },
+            {
+                "description": "another valid base64-encoded JSON document",
+                "data": "eyJib28iOiAyMCwgImZvbyI6ICJiYXoifQ==",
+                "valid": true
+            },
+            {
+                "description": "an invalid base64-encoded JSON document; validates false",
+                "data": "eyJib28iOiAyMH0=",
+                "valid": false
+            },
+            {
+                "description": "an empty object as a base64-encoded JSON document; validates false",
+                "data": "e30=",
+                "valid": false
+            },
+            {
+                "description": "an empty array as a base64-encoded JSON document",
+                "data": "W10=",
+                "valid": true
+            },
+            {
+                "description": "a validly-encoded invalid JSON document; validates false",
+                "data": "ezp9Cg==",
+                "valid": false
+            },
+            {
+                "description": "an invalid base64 string that is valid JSON; validates false",
+                "data": "{}",
+                "valid": false
+            },
+            {
+                "description": "ignores non-strings",
+                "data": 100,
+                "valid": true
+            }
+        ]
+    },
+    {
+        "description": "contentSchema without contentMediaType",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "contentEncoding": "base64",
+            "contentSchema": { "required": ["foo"], "properties": { "foo": { "type": "string" } } }
+        },
+        "tests": [
+            {
+                "description": "a valid base64-encoded JSON document",
+                "data": "eyJmb28iOiAiYmFyIn0K",
+                "valid": true
+            },
+            {
+                "description": "another valid base64-encoded JSON document",
+                "data": "eyJib28iOiAyMCwgImZvbyI6ICJiYXoifQ==",
+                "valid": true
+            },
+            {
+                "description": "an invalid base64-encoded JSON document; validates true",
+                "data": "eyJib28iOiAyMH0=",
+                "valid": true
+            },
+            {
+                "description": "an empty object as a base64-encoded JSON document; validates true",
+                "data": "e30=",
+                "valid": true
+            },
+            {
+                "description": "an empty array as a base64-encoded JSON document",
+                "data": "W10=",
+                "valid": true
+            },
+            {
+                "description": "a validly-encoded invalid JSON document; validates true",
+                "data": "ezp9Cg==",
+                "valid": true
+            },
+            {
+                "description": "an invalid base64 string that is valid JSON; validates false",
+                "data": "{}",
+                "valid": false
+            },
+            {
+                "description": "ignores non-strings",
+                "data": 100,
+                "valid": true
+            }
+        ]
+    },
+    {
+        "description": "contentSchema without contentEncoding",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "contentMediaType": "application/json",
+            "contentSchema": { "required": ["foo"], "properties": { "foo": { "type": "string" } } }
+        },
+        "tests": [
+            {
+                "description": "a valid JSON document",
+                "data": "{\"foo\": \"bar\"}",
+                "valid": true
+            },
+            {
+                "description": "another valid base64-encoded JSON document",
+                "data": "{\"boo\": 20, \"foo\": \"baz\"}",
+                "valid": true
+            },
+            {
+                "description": "an empty object; validates false",
+                "data": "{}",
+                "valid": false
+            },
+            {
+                "description": "an empty array; validates false",
+                "data": "[]",
+                "valid": true
+            },
+            {
+                "description": "invalid JSON document; validates false",
+                "data": "[}",
+                "valid": false
+            },
+            {
+                "description": "ignores non-strings",
+                "data": 100,
+                "valid": true
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/optional/format/date.json

@@ -0,0 +1,16 @@
+[
+    {
+        "description": "validation of date strings",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "format": "date"
+        },
+        "tests": [
+            {
+                "description": "contains alphabets",
+                "data": "yyyy-mm-dd",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/optional/format/duration.json

@@ -0,0 +1,16 @@
+[
+    {
+        "description": "validation of duration strings",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "format": "duration"
+        },
+        "tests": [
+            {
+                "description": "more than one T",
+                "data": "PT1MT1S",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/optional/format/email.json

@@ -0,0 +1,31 @@
+[
+    {
+        "description": "validation of duration strings",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "format": "email"
+        },
+        "tests": [
+            {
+                "description": "non printable character",
+                "data": "a\tb@gmail.com",
+                "valid": false
+            },
+            {
+                "description": "tab ok if quoted",
+                "data": "\"a\tb\"@gmail.com",
+                "valid": true
+            },
+            {
+                "description": "quote inside quoted",
+                "data": "\"a\"b\"@gmail.com",
+                "valid": false
+            },
+            {
+                "description": "backslash inside quoted",
+                "data": "\"a\\b\"@gmail.com",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/optional/format/time.json

@@ -0,0 +1,23 @@
+[
+    {
+        "description": "validation of time strings",
+        "schema": { "format": "time" },
+        "tests": [
+            {
+                "description": "contains alphabets",
+                "data": "ab:cd:efZ",
+                "valid": false
+            },
+            {
+                "description": "no digit in second fraction",
+                "data": "23:20:50.Z",
+                "valid": false
+            },
+            {
+                "description": "alphabets in offset",
+                "data": "08:30:06+ab:cd",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/properties.json

@@ -0,0 +1,26 @@
+[
+    {
+        "description": "special characters",
+        "schema": {
+            "properties": {
+                "a%20b/c": { "type": "number" }
+            }
+        },
+        "tests": [
+            {
+                "description": "valid",
+                "data": {
+                    "a%20b/c": 1
+                },
+                "valid": true
+            },
+            {
+                "description": "invalid",
+                "data": {
+                    "a%20b/c": "hello"
+                },
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/ref.json

@@ -0,0 +1,74 @@
+[
+    {
+        "description": "percent-encoded json-pointer",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "a b": {"type": "number"}
+            },
+            "$ref": "#/$defs/a%20b"
+        },
+        "tests": [
+            {
+                "description": "match",
+                "data": 1,
+                "valid": true
+            },
+            {
+                "description": "mismatch",
+                "data": "foobar",
+                "valid": false
+            }
+        ]
+    },
+    {
+        "description": "precent in resource ptr",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "a%20b": {
+                    "$id": "http://temp.com/ab",
+                    "type": "number"
+                }
+            },
+            "$ref": "http://temp.com/ab"
+        },
+        "tests": [
+            {
+                "description": "match",
+                "data": 1,
+                "valid": true
+            },
+            {
+                "description": "mismatch",
+                "data": "foobar",
+                "valid": false
+            }
+        ]
+    },
+    {
+        "description": "precent in anchor ptr",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "a%20b": {
+                    "$anchor": "abcd",
+                    "type": "number"
+                }
+            },
+            "$ref": "#abcd"
+        },
+        "tests": [
+            {
+                "description": "match",
+                "data": 1,
+                "valid": true
+            },
+            {
+                "description": "mismatch",
+                "data": "foobar",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/unevaluatedProperties.json

@@ -0,0 +1,57 @@
+[
+  {
+    "description": "unevaluatedProperties with a failing $ref",
+    "schema": {
+      "$schema": "https://json-schema.org/draft/2020-12/schema",
+      "$defs": {
+        "child": {
+          "type": "object",
+          "properties": {
+            "prop2": { "type": "string" }
+          },
+          "unevaluatedProperties": false
+        }
+      },
+      "type": "object",
+      "properties": {
+        "prop1": { "type": "string" },
+        "child_schema": { "$ref": "#/$defs/child" }
+      },
+      "unevaluatedProperties": false
+    },
+    "tests": [
+      {
+        "description": "unevaluated property in child should fail validation",
+        "data": {
+          "prop1": "value1",
+          "child_schema": {
+            "prop2": "value2",
+            "extra_prop_in_child": "this should fail"
+          }
+        },
+        "valid": false
+      },
+      {
+        "description": "a valid instance should pass",
+        "data": {
+          "prop1": "value1",
+          "child_schema": {
+            "prop2": "value2"
+          }
+        },
+        "valid": true
+      },
+      {
+        "description": "unevaluated property in parent should fail",
+        "data": {
+          "prop1": "value1",
+          "child_schema": {
+            "prop2": "value2"
+          },
+          "extra_prop_in_parent": "this should fail"
+        },
+        "valid": false
+      }
+    ]
+  }
+]

validator/tests/Extra-Test-Suite/tests/draft2020-12/uniqueItems.json

@@ -0,0 +1,21 @@
+[
+    {
+        "description": "zero fraction",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "uniqueItems": true
+        },
+        "tests": [
+            {
+                "description": "with fraction",
+                "data": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, 2.0],
+                "valid": false 
+            },
+            {
+                "description": "without fraction",
+                "data": [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -1, -2, -3, -4, -5, -6, -7, -8, -9, -10, 2],
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft4/dependencies.json

@@ -0,0 +1,27 @@
+[
+    {
+        "description": "percent in dependencies",
+        "schema": {
+            "dependencies": {
+                "a%20b": { "required": ["x"] }
+            }
+        },
+        "tests": [
+            {
+                "description": "valid",
+                "data": {
+                    "a%20b": null,
+                    "x": 1
+                },
+                "valid": true
+            },
+            {
+                "description": "invalid",
+                "data": {
+                    "a%20b": null
+                },
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft7/if-then-else.json

@@ -0,0 +1,50 @@
+[
+    {
+        "description": "skip then when if is false",
+        "schema": {
+            "if": false,
+            "then": {
+                "$ref": "blah/blah.json"
+            },
+            "else": {
+                "type": "number"
+            }
+        },
+        "tests": [
+            {
+                "description": "number is valid",
+                "data": 0,
+                "valid": true
+            },
+            {
+                "description": "string is invalid",
+                "data": "hello",
+                "valid": false
+            }
+        ]
+    },
+    {
+        "description": "skip else when if is true",
+        "schema": {
+            "if": true,
+            "then": {
+                "type": "number"
+            },
+            "else": {
+                "$ref": "blah/blah.json"
+            }
+        },
+        "tests": [
+            {
+                "description": "number is valid",
+                "data": 0,
+                "valid": true
+            },
+            {
+                "description": "string is invalid",
+                "data": "hello",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/Extra-Test-Suite/tests/draft7/optional/format/period.json

@@ -0,0 +1,98 @@
+[
+    {
+        "description": "validation of period",
+        "schema": { "format": "period" },
+        "tests": [
+            {
+                "description": "all string formats ignore integers",
+                "data": 12,
+                "valid": true
+            },
+            {
+                "description": "all string formats ignore floats",
+                "data": 13.7,
+                "valid": true
+            },
+            {
+                "description": "all string formats ignore objects",
+                "data": {},
+                "valid": true
+            },
+            {
+                "description": "all string formats ignore arrays",
+                "data": [],
+                "valid": true
+            },
+            {
+                "description": "all string formats ignore booleans",
+                "data": false,
+                "valid": true
+            },
+            {
+                "description": "all string formats ignore nulls",
+                "data": null,
+                "valid": true
+            },
+            {
+                "description": "both-explicit",
+                "data": "1963-06-19T08:30:06Z/1963-06-19T08:30:07Z",
+                "valid": true
+            },
+            {
+                "description": "start-explicit",
+                "data": "1963-06-19T08:30:06Z/P4DT12H30M5S",
+                "valid": true
+            },
+            {
+                "description": "end-explicit",
+                "data": "P4DT12H30M5S/1963-06-19T08:30:06Z",
+                "valid": true
+            },
+            {
+                "description": "none-explicit",
+                "data": "P4DT12H30M5S/P4DT12H30M5S",
+                "valid": false
+            },
+            {
+                "description": "just date",
+                "data": "1963-06-19T08:30:06Z",
+                "valid": false
+            },
+            {
+                "description": "just duration",
+                "data": "P4DT12H30M5S",
+                "valid": false
+            },
+            {
+                "description": "more than two",
+                "data": "1963-06-19T08:30:06Z/1963-06-19T08:30:07Z/1963-06-19T08:30:07Z",
+                "valid": false
+            },
+            {
+                "description": "separated by space",
+                "data": "1963-06-19T08:30:06Z 1963-06-19T08:30:07Z",
+                "valid": false
+            },
+            {
+                "description": "separated by hyphen",
+                "data": "1963-06-19T08:30:06Z-1963-06-19T08:30:07Z",
+                "valid": false
+            },
+            {
+                "description": "invalid components",
+                "data": "foo/bar",
+                "valid": false
+            },
+            {
+                "description": "emtpy components",
+                "data": "/",
+                "valid": false
+            },
+            {
+                "description": "empty string",
+                "data": "",
+                "valid": false
+            }
+        ]
+    }
+]

validator/tests/compiler.rs

@@ -0,0 +1,87 @@
+use std::error::Error;
+
+use boon::{Compiler, Schemas};
+use serde_json::json;
+
+#[test]
+fn test_metaschema_resource() -> Result<(), Box<dyn Error>> {
+  let main_schema = json!({
+    "$schema": "http://tmp.com/meta.json",
+    "type": "number"
+  });
+  let meta_schema = json!({
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "$vocabulary": {
+      "https://json-schema.org/draft/2020-12/vocab/applicator": true,
+      "https://json-schema.org/draft/2020-12/vocab/core": true
+    },
+    "allOf": [
+      { "$ref": "https://json-schema.org/draft/2020-12/meta/applicator" },
+      { "$ref": "https://json-schema.org/draft/2020-12/meta/core" }
+    ]
+  });
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.add_resource("schema.json", main_schema)?;
+  compiler.add_resource("http://tmp.com/meta.json", meta_schema)?;
+  compiler.compile("schema.json", &mut schemas)?;
+
+  Ok(())
+}
+
+#[test]
+fn test_compile_anchor() -> Result<(), Box<dyn Error>> {
+  let schema = json!({
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "$defs": {
+      "x": {
+        "$anchor": "a1",
+        "type": "number"
+      }
+    }
+  });
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.add_resource("schema.json", schema)?;
+  let sch_index1 = compiler.compile("schema.json#a1", &mut schemas)?;
+  let sch_index2 = compiler.compile("schema.json#/$defs/x", &mut schemas)?;
+  assert_eq!(sch_index1, sch_index2);
+
+  Ok(())
+}
+
+#[test]
+fn test_compile_nonstd() -> Result<(), Box<dyn Error>> {
+  let schema = json!({
+    "components": {
+      "schemas": {
+        "foo" : {
+          "$schema": "https://json-schema.org/draft/2020-12/schema",
+          "$defs": {
+            "x": {
+              "$anchor": "a",
+              "type": "number"
+            },
+            "y": {
+              "$id": "http://temp.com/y",
+              "type": "string"
+            }
+          },
+          "oneOf": [
+            { "$ref": "#a" },
+            { "$ref": "http://temp.com/y" }
+          ]
+        }
+      }
+    }
+  });
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.add_resource("schema.json", schema)?;
+  compiler.compile("schema.json#/components/schemas/foo", &mut schemas)?;
+
+  Ok(())
+}

validator/tests/debug.json

@@ -0,0 +1,33 @@
+{
+    "remotes": {
+        "http://localhost:1234/draft2020-12/locationIndependentIdentifier.json": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "refToInteger": {
+                    "$ref": "#foo"
+                },
+                "A": {
+                    "$anchor": "foo",
+                    "type": "integer"
+                }
+            }
+        }
+    },
+    "schema": {
+        "$schema": "https://json-schema.org/draft/2020-12/schema",
+        "type": "object",
+        "properties": {
+             "a": {
+                "$ref": "http://localhost:1234/draft2020-12/locationIndependentIdentifier.json#foo"
+              },
+              "b": {
+                "$ref": "http://localhost:1234/draft2020-12/locationIndependentIdentifier.json#foo"
+              } 
+        }
+    },
+    "data": {
+        "a": 1,
+        "b": "hello"
+    },
+    "valid": false
+}

validator/tests/debug.rs

@@ -0,0 +1,41 @@
+use std::{error::Error, fs::File};
+
+use boon::{Compiler, Schemas, UrlLoader};
+use serde_json::{Map, Value};
+
+#[test]
+fn test_debug() -> Result<(), Box<dyn Error>> {
+  let test: Value = serde_json::from_reader(File::open("tests/debug.json")?)?;
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.enable_format_assertions();
+  compiler.enable_content_assertions();
+  let remotes = Remotes(test["remotes"].as_object().unwrap().clone());
+  compiler.use_loader(Box::new(remotes));
+  let url = "http://debug.com/schema.json";
+  compiler.add_resource(url, test["schema"].clone())?;
+  let sch = compiler.compile(url, &mut schemas)?;
+  let result = schemas.validate(&test["data"], sch, None);
+  if let Err(e) = &result {
+    for line in format!("{e}").lines() {
+      println!("    {line}");
+    }
+    for line in format!("{e:#}").lines() {
+      println!("    {line}");
+    }
+    println!("{:#}", e.detailed_output());
+  }
+  assert_eq!(result.is_ok(), test["valid"].as_bool().unwrap());
+  Ok(())
+}
+
+struct Remotes(Map<String, Value>);
+
+impl UrlLoader for Remotes {
+  fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+    if let Some(v) = self.0.get(url) {
+      return Ok(v.clone());
+    }
+    Err("remote not found")?
+  }
+}

validator/tests/examples.rs

@@ -0,0 +1,230 @@
+use std::{error::Error, fs::File};
+
+use boon::{Compiler, Decoder, FileLoader, Format, MediaType, Schemas, SchemeUrlLoader, UrlLoader};
+use serde::de::IgnoredAny;
+use serde_json::{json, Value};
+use url::Url;
+
+#[test]
+fn example_from_files() -> Result<(), Box<dyn Error>> {
+  let schema_file = "tests/examples/schema.json";
+  let instance: Value = serde_json::from_reader(File::open("tests/examples/instance.json")?)?;
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  let sch_index = compiler.compile(schema_file, &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_ok());
+
+  Ok(())
+}
+
+/**
+This example shows how to load json schema from strings.
+
+The schema url used plays important role in resolving
+schema references.
+
+You can see that `cat.json` is resolved internally to
+another string schema where as dog.json is resolved
+to local file.
+*/
+#[test]
+fn example_from_strings() -> Result<(), Box<dyn Error>> {
+  let cat_schema: Value = json!({
+    "type": "object",
+    "properties": {
+      "speak": { "const": "meow" }
+    },
+    "required": ["speak"]
+  });
+  let pet_schema: Value = json!({
+    "oneOf": [
+      { "$ref": "dog.json" },
+      { "$ref": "cat.json" }
+    ]
+  });
+  let instance: Value = json!({"speak": "bow"});
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.add_resource("tests/examples/pet.json", pet_schema)?;
+  compiler.add_resource("tests/examples/cat.json", cat_schema)?;
+  let sch_index = compiler.compile("tests/examples/pet.json", &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_ok());
+
+  Ok(())
+}
+
+#[test]
+#[ignore]
+fn example_from_https() -> Result<(), Box<dyn Error>> {
+  let schema_url = "https://json-schema.org/learn/examples/geographical-location.schema.json";
+  let instance: Value = json!({"latitude": 48.858093, "longitude": 2.294694});
+
+  struct HttpUrlLoader;
+  impl UrlLoader for HttpUrlLoader {
+    fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+      let reader = ureq::get(url).call()?.into_reader();
+      Ok(serde_json::from_reader(reader)?)
+    }
+  }
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  let mut loader = SchemeUrlLoader::new();
+  loader.register("file", Box::new(FileLoader));
+  loader.register("http", Box::new(HttpUrlLoader));
+  loader.register("https", Box::new(HttpUrlLoader));
+  compiler.use_loader(Box::new(loader));
+  let sch_index = compiler.compile(schema_url, &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_ok());
+
+  Ok(())
+}
+
+#[test]
+fn example_from_yaml_files() -> Result<(), Box<dyn Error>> {
+  let schema_file = "tests/examples/schema.yml";
+  let instance: Value = serde_yaml::from_reader(File::open("tests/examples/instance.yml")?)?;
+
+  struct FileUrlLoader;
+  impl UrlLoader for FileUrlLoader {
+    fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+      let url = Url::parse(url)?;
+      let path = url.to_file_path().map_err(|_| "invalid file path")?;
+      let file = File::open(&path)?;
+      if path
+        .extension()
+        .filter(|&ext| ext == "yaml" || ext == "yml")
+        .is_some()
+      {
+        Ok(serde_yaml::from_reader(file)?)
+      } else {
+        Ok(serde_json::from_reader(file)?)
+      }
+    }
+  }
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  let mut loader = SchemeUrlLoader::new();
+  loader.register("file", Box::new(FileUrlLoader));
+  compiler.use_loader(Box::new(loader));
+  let sch_index = compiler.compile(schema_file, &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_ok());
+
+  Ok(())
+}
+
+#[test]
+fn example_custom_format() -> Result<(), Box<dyn Error>> {
+  let schema_url = "http://tmp/schema.json";
+  let schema: Value = json!({"type": "string", "format": "palindrome"});
+  let instance: Value = json!("step on no pets");
+
+  fn is_palindrome(v: &Value) -> Result<(), Box<dyn Error>> {
+    let Value::String(s) = v else {
+      return Ok(()); // applicable only on strings
+    };
+    let mut chars = s.chars();
+    while let (Some(c1), Some(c2)) = (chars.next(), chars.next_back()) {
+      if c1 != c2 {
+        Err("char mismatch")?;
+      }
+    }
+    Ok(())
+  }
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.enable_format_assertions(); // in draft2020-12 format assertions are not enabled by default
+  compiler.register_format(Format {
+    name: "palindrome",
+    func: is_palindrome,
+  });
+  compiler.add_resource(schema_url, schema)?;
+  let sch_index = compiler.compile(schema_url, &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_ok());
+
+  Ok(())
+}
+
+#[test]
+fn example_custom_content_encoding() -> Result<(), Box<dyn Error>> {
+  let schema_url = "http://tmp/schema.json";
+  let schema: Value = json!({"type": "string", "contentEncoding": "hex"});
+  let instance: Value = json!("aBcdxyz");
+
+  fn decode(b: u8) -> Result<u8, Box<dyn Error>> {
+    match b {
+      b'0'..=b'9' => Ok(b - b'0'),
+      b'a'..=b'f' => Ok(b - b'a' + 10),
+      b'A'..=b'F' => Ok(b - b'A' + 10),
+      _ => Err("decode_hex: non-hex char")?,
+    }
+  }
+  fn decode_hex(s: &str) -> Result<Vec<u8>, Box<dyn Error>> {
+    if s.len() % 2 != 0 {
+      Err("decode_hex: odd length")?;
+    }
+    let mut bytes = s.bytes();
+    let mut out = Vec::with_capacity(s.len() / 2);
+    for _ in 0..out.len() {
+      if let (Some(b1), Some(b2)) = (bytes.next(), bytes.next()) {
+        out.push(decode(b1)? << 4 | decode(b2)?);
+      } else {
+        Err("decode_hex: non-ascii char")?;
+      }
+    }
+    Ok(out)
+  }
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.enable_content_assertions(); // content assertions are not enabled by default
+  compiler.register_content_encoding(Decoder {
+    name: "hex",
+    func: decode_hex,
+  });
+  compiler.add_resource(schema_url, schema)?;
+  let sch_index = compiler.compile(schema_url, &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_err());
+
+  Ok(())
+}
+
+#[test]
+fn example_custom_content_media_type() -> Result<(), Box<dyn Error>> {
+  let schema_url = "http://tmp/schema.json";
+  let schema: Value = json!({"type": "string", "contentMediaType": "application/yaml"});
+  let instance: Value = json!("name:foobar");
+
+  fn check_yaml(bytes: &[u8], deserialize: bool) -> Result<Option<Value>, Box<dyn Error>> {
+    if deserialize {
+      return Ok(Some(serde_yaml::from_slice(bytes)?));
+    }
+    serde_yaml::from_slice::<IgnoredAny>(bytes)?;
+    Ok(None)
+  }
+
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.enable_content_assertions(); // content assertions are not enabled by default
+  compiler.register_content_media_type(MediaType {
+    name: "application/yaml",
+    json_compatible: true,
+    func: check_yaml,
+  });
+  compiler.add_resource(schema_url, schema)?;
+  let sch_index = compiler.compile(schema_url, &mut schemas)?;
+  let result = schemas.validate(&instance, sch_index, None);
+  assert!(result.is_ok());
+
+  Ok(())
+}

validator/tests/examples/dog.json

@@ -0,0 +1,7 @@
+{
+    "type": "object",
+    "properties": {
+        "speak": { "const": "bow" }
+    },
+    "required": ["speak"]
+}

validator/tests/examples/instance.json

@@ -0,0 +1,4 @@
+{
+    "firstName": "Santhosh Kumar",
+    "lastName": "Tekuri"
+}

validator/tests/examples/instance.yml

@@ -0,0 +1,2 @@
+firstName: Santhosh Kumar
+lastName: Tekuri

validator/tests/examples/sample schema.json

@@ -0,0 +1,12 @@
+{
+    "type": "object",
+    "properties": {
+        "firstName": {
+            "type": "string"
+        },
+        "lastName": {
+            "type": "string"
+        }
+    },
+    "required": ["firstName", "lastName"]
+}

validator/tests/examples/schema.json

@@ -0,0 +1,12 @@
+{
+    "type": "object",
+    "properties": {
+        "firstName": {
+            "type": "string"
+        },
+        "lastName": {
+            "type": "string"
+        }
+    },
+    "required": ["firstName", "lastName"]
+}

validator/tests/examples/schema.yml

@@ -0,0 +1,9 @@
+type: object
+properties:
+  firstName:
+    type: string
+  lastName:
+    type: string
+required:
+- firstName
+- lastName

validator/tests/filepaths.rs

@@ -0,0 +1,44 @@
+use std::fs;
+
+use boon::{CompileError, Compiler, Schemas};
+
+fn test(path: &str) -> Result<(), CompileError> {
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  compiler.compile(path, &mut schemas)?;
+  Ok(())
+}
+
+#[test]
+fn test_absolute() -> Result<(), CompileError> {
+  let path = fs::canonicalize("tests/examples/schema.json").unwrap();
+  test(path.to_string_lossy().as_ref())
+}
+
+#[test]
+fn test_relative_slash() -> Result<(), CompileError> {
+  test("tests/examples/schema.json")
+}
+
+#[test]
+#[cfg(windows)]
+fn test_relative_backslash() -> Result<(), CompileError> {
+  test("tests\\examples\\schema.json")
+}
+
+#[test]
+fn test_absolutei_space() -> Result<(), CompileError> {
+  let path = fs::canonicalize("tests/examples/sample schema.json").unwrap();
+  test(path.to_string_lossy().as_ref())
+}
+
+#[test]
+fn test_relative_slash_space() -> Result<(), CompileError> {
+  test("tests/examples/sample schema.json")
+}
+
+#[test]
+#[cfg(windows)]
+fn test_relative_backslash_space() -> Result<(), CompileError> {
+  test("tests\\examples\\sample schema.json")
+}

validator/tests/invalid-schemas.json

@@ -0,0 +1,244 @@
+[
+    {
+        "description": "InvalidJsonPointer",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$ref": "#/a~0b~~cd"
+        },
+        "errors": [
+            "InvalidJsonPointer(\"http://fake.com/schema.json#/a~0b~~cd\")"
+        ]
+    },
+    {
+        "description": "UnsupportedUrlScheme",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$ref": "ftp://mars.com/schema.json"
+        },
+        "errors": [
+            "UnsupportedUrlScheme { url: \"ftp://mars.com/schema.json\" }"
+        ]
+    },
+    {
+        "description": "ValidationError",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "patternProperties": {
+                "^(abc]": {
+                    "type": "string"
+                }
+            }
+        },
+        "errors": [
+            "ValidationError { url: \"http://fake.com/schema.json#\""
+        ]
+    },
+    {
+        "description": "ValidationError-nonsubschema",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "dummy": {
+                "type": 1
+            },
+            "$ref": "#/dummy"
+        },
+        "errors": [
+            "ValidationError { url: \"http://fake.com/schema.json#/dummy\""
+        ]
+    },
+    {
+        "description": "JsonPointerNotFound-obj",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$ref": "#/$defs/something"
+        },
+        "errors": [
+            "JsonPointerNotFound(\"http://fake.com/schema.json#/$defs/something\")"
+        ]
+    },
+    {
+        "description": "JsonPointerNotFound-arr-pos",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$ref": "#/dummy/0",
+            "dummy": []
+        },
+        "errors": [
+            "JsonPointerNotFound(\"http://fake.com/schema.json#/dummy/0\")"
+        ]
+    },
+    {
+        "description": "JsonPointerNotFound-arr-neg",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$ref": "#/dummy/-1",
+            "dummy": []
+        },
+        "errors": [
+            "JsonPointerNotFound(\"http://fake.com/schema.json#/dummy/-1\")"
+        ]
+    },
+    {
+        "description": "JsonPointerNotFound-primitive",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$ref": "#/$schema/something"
+        },
+        "errors": [
+            "JsonPointerNotFound(\"http://fake.com/schema.json#/$schema/something\")"
+        ]
+    },
+    {
+        "description": "InvalidRegex",
+        "schema": {
+            "$schema": "https://json-schema.org/draft-04/schema",
+            "patternProperties": {
+                "^(abc]": {
+                    "type": "string"
+                }
+            }
+        },
+        "errors": [
+            "InvalidRegex { url: \"http://fake.com/schema.json#/patternProperties\", regex: \"^(abc]\", "
+        ]
+    },
+    {
+        "description": "DuplicateId",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "a": {
+                    "$id": "http://a.com/b",
+                    "$defs": {
+                        "b": {
+                            "$id": "a.json"
+                        },
+                        "c": {
+                            "$id": "a.json"
+                        }
+                    }
+                }
+            }
+        },
+        "errors": [
+            "DuplicateId { url: \"http://fake.com/schema.json\", id: \"http://a.com/a.json\", ",
+            "\"/$defs/a/$defs/b\"",
+            "\"/$defs/a/$defs/c\""
+        ]
+    },
+    {
+        "description": "DuplicateAnchor",
+        "schema": {
+            "$schema": "https://json-schema.org/draft/2020-12/schema",
+            "$defs": {
+                "a": {
+                    "$id": "http://a.com/b",
+                    "$defs": {
+                        "b": {
+                            "$anchor": "a1"
+                        },
+                        "c": {
+                            "$anchor": "a1"
+                        }
+                    }
+                }
+            }
+        },
+        "errors": [
+            "DuplicateAnchor { anchor: \"a1\", url: \"http://fake.com/schema.json\", ",
+            "\"/$defs/a/$defs/b\"",
+            "\"/$defs/a/$defs/c\""
+        ]
+    },
+    {
+        "description": "UnsupportedDraft",
+        "remotes": {
+            "http://remotes/a.json": {
+                "$schema": "http://remotes/b.json"
+            },
+            "http://remotes/b.json": {
+                "$schema": "http://remotes/b.json"
+            }
+        },
+        "schema": {
+            "$schema": "http://remotes/a.json"
+        },
+        "errors": [
+            "UnsupportedDraft { url: \"http://remotes/b.json\" }"
+        ]
+    },
+    {
+        "description": "MetaSchemaCycle",
+        "remotes": {
+            "http://remotes/a.json": {
+                "$schema": "http://remotes/b.json"
+            },
+            "http://remotes/b.json": {
+                "$schema": "http://remotes/a.json"
+            }
+        },
+        "schema": {
+            "$schema": "http://remotes/a.json"
+        },
+        "errors": [
+            "MetaSchemaCycle { url: \"http://remotes/a.json\" }"
+        ]
+    },
+    {
+        "description": "AnchorNotFound-local",
+        "schema": {
+            "$ref": "sample.json#abcd",
+            "$defs": {
+                "a": {
+                    "$id": "sample.json"
+                }
+            }
+        },
+        "errors": [
+            "AnchorNotFound { url: \"http://fake.com/schema.json\", reference: \"http://fake.com/sample.json#abcd\" }"
+        ]
+    },
+    {
+        "description": "AnchorNotFound-remote",
+        "remotes": {
+            "http://remotes/a.json": {}
+        },
+        "schema": {
+            "$ref": "http://remotes/a.json#abcd"
+        },
+        "errors": [
+            "AnchorNotFound { url: \"http://remotes/a.json\", reference: \"http://remotes/a.json#abcd\" }"
+        ]
+    },
+    {
+        "description": "UnsupportedVocabulary-required",
+        "remotes": {
+            "http://remotes/a.json": {
+                "$schema": "https://json-schema.org/draft/2020-12/schema#",
+                "$vocabulary": {
+                    "https://json-schema.org/draft/2019-09/vocab/format": true
+                }
+            }
+        },
+        "schema": {
+            "$schema": "http://remotes/a.json"
+        },
+        "errors": [
+            "UnsupportedVocabulary { url: \"http://remotes/a.json\", vocabulary: \"https://json-schema.org/draft/2019-09/vocab/format\" }"
+        ]
+    },
+    {
+        "description": "UnsupportedVocabulary-optioanl",
+        "remotes": {
+            "http://remotes/a.json": {
+                "$schema": "https://json-schema.org/draft/2020-12/schema#",
+                "$vocabulary": {
+                    "https://json-schema.org/draft/2019-09/vocab/format": false
+                }
+            }
+        },
+        "schema": {
+            "$schema": "http://remotes/a.json"
+        }
+    }
+]

validator/tests/invalid-schemas.rs

@@ -0,0 +1,67 @@
+use std::{collections::HashMap, error::Error, fs::File};
+
+use boon::{CompileError, Compiler, Schemas, UrlLoader};
+use serde::Deserialize;
+use serde_json::Value;
+
+#[derive(Debug, Deserialize)]
+struct Test {
+  description: String,
+  remotes: Option<HashMap<String, Value>>,
+  schema: Value,
+  errors: Option<Vec<String>>,
+}
+
+#[test]
+fn test_invalid_schemas() -> Result<(), Box<dyn Error>> {
+  let file = File::open("tests/invalid-schemas.json")?;
+  let tests: Vec<Test> = serde_json::from_reader(file)?;
+  for test in tests {
+    println!("{}", test.description);
+    match compile(&test) {
+      Ok(_) => {
+        if test.errors.is_some() {
+          Err("want compilation to fail")?
+        }
+      }
+      Err(e) => {
+        println!("  {e}");
+        let error = format!("{e:?}");
+        let Some(errors) = &test.errors else {
+          Err("want compilation to succeed")?
+        };
+        for want in errors {
+          if !error.contains(want) {
+            println!("  got {error}");
+            println!("  want {want}");
+            panic!("error mismatch");
+          }
+        }
+      }
+    }
+  }
+  Ok(())
+}
+
+fn compile(test: &Test) -> Result<(), CompileError> {
+  let mut schemas = Schemas::new();
+  let mut compiler = Compiler::new();
+  let url = "http://fake.com/schema.json";
+  if let Some(remotes) = &test.remotes {
+    compiler.use_loader(Box::new(Remotes(remotes.clone())));
+  }
+  compiler.add_resource(url, test.schema.clone())?;
+  compiler.compile(url, &mut schemas)?;
+  Ok(())
+}
+
+struct Remotes(HashMap<String, Value>);
+
+impl UrlLoader for Remotes {
+  fn load(&self, url: &str) -> Result<Value, Box<dyn Error>> {
+    if let Some(v) = self.0.get(url) {
+      return Ok(v.clone());
+    }
+    Err("remote not found")?
+  }
+}

validator/tests/output.rs

@@ -0,0 +1,122 @@
+use std::{env, error::Error, fs::File, path::Path};
+
+use boon::{Compiler, Draft, Schemas};
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+
+#[test]
+fn test_suites() -> Result<(), Box<dyn Error>> {
+  if let Ok(suite) = env::var("TEST_SUITE") {
+    test_suite(&suite)?;
+  } else {
+    test_suite("tests/JSON-Schema-Test-Suite")?;
+    test_suite("tests/Extra-Suite")?;
+  }
+  Ok(())
+}
+
+fn test_suite(suite: &str) -> Result<(), Box<dyn Error>> {
+  test_folder(suite, "draft2019-09", Draft::V2019_09)?;
+  test_folder(suite, "draft2020-12", Draft::V2020_12)?;
+  Ok(())
+}
+
+fn test_folder(suite: &str, folder: &str, draft: Draft) -> Result<(), Box<dyn Error>> {
+  let output_schema_url = format!(
+    "https://json-schema.org/draft/{}/output/schema",
+    folder.strip_prefix("draft").unwrap()
+  );
+  let prefix = Path::new(suite).join("output-tests");
+  let folder = prefix.join(folder);
+  let content = folder.join("content");
+  if !content.is_dir() {
+    return Ok(());
+  }
+  let output_schema: Value =
+    serde_json::from_reader(File::open(folder.join("output-schema.json"))?)?;
+  for entry in content.read_dir()? {
+    let entry = entry?;
+    if !entry.file_type()?.is_file() {
+      continue;
+    };
+    let entry_path = entry.path();
+    println!("{}", entry_path.strip_prefix(&prefix)?.to_str().unwrap());
+    let groups: Vec<Group> = serde_json::from_reader(File::open(entry_path)?)?;
+    for group in groups {
+      println!("  {}", group.description);
+      let mut schemas = Schemas::new();
+      let mut compiler = Compiler::new();
+      compiler.set_default_draft(draft);
+      let schema_url = "http://output-tests/schema";
+      compiler.add_resource(schema_url, group.schema)?;
+      let sch = compiler.compile(schema_url, &mut schemas)?;
+      for test in group.tests {
+        println!("    {}", test.description);
+        match schemas.validate(&test.data, sch, None) {
+          Ok(_) => println!("      validation success"),
+          Err(e) => {
+            if let Some(sch) = test.output.basic {
+              let mut schemas = Schemas::new();
+              let mut compiler = Compiler::new();
+              compiler.set_default_draft(draft);
+              compiler.add_resource(&output_schema_url, output_schema.clone())?;
+              let schema_url = "http://output-tests/schema";
+              compiler.add_resource(schema_url, sch)?;
+              let sch = compiler.compile(schema_url, &mut schemas)?;
+              let basic: Value = serde_json::from_str(&e.basic_output().to_string())?;
+              let result = schemas.validate(&basic, sch, None);
+              if let Err(e) = result {
+                println!("{basic:#}\n");
+                for line in format!("{e}").lines() {
+                  println!("      {line}");
+                }
+                panic!("basic output did not match");
+              }
+            }
+            if let Some(sch) = test.output.detailed {
+              let mut schemas = Schemas::new();
+              let mut compiler = Compiler::new();
+              compiler.set_default_draft(draft);
+              compiler.add_resource(&output_schema_url, output_schema.clone())?;
+              let schema_url = "http://output-tests/schema";
+              compiler.add_resource(schema_url, sch)?;
+              let sch = compiler.compile(schema_url, &mut schemas)?;
+              let detailed: Value =
+                serde_json::from_str(&e.detailed_output().to_string())?;
+              let result = schemas.validate(&detailed, sch, None);
+              if let Err(e) = result {
+                println!("{detailed:#}\n");
+                for line in format!("{e}").lines() {
+                  println!("      {line}");
+                }
+                panic!("detailed output did not match");
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+
+  Ok(())
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Group {
+  description: String,
+  schema: Value,
+  tests: Vec<Test>,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Test {
+  description: String,
+  data: Value,
+  output: Output,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Output {
+  basic: Option<Value>,
+  detailed: Option<Value>,
+}

validator/tests/suite.rs

@@ -0,0 +1,120 @@
+use std::{env, error::Error, ffi::OsStr, fs::File, path::Path};
+
+use boon::{Compiler, Draft, Schemas, UrlLoader};
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+
+static SKIP: [&str; 2] = [
+  "zeroTerminatedFloats.json", // only draft4: this behavior is changed in later drafts
+  "float-overflow.json",
+];
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Group {
+  description: String,
+  schema: Value,
+  tests: Vec<Test>,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+struct Test {
+  description: String,
+  data: Value,
+  valid: bool,
+}
+
+#[test]
+fn test_suites() -> Result<(), Box<dyn Error>> {
+  if let Ok(suite) = env::var("TEST_SUITE") {
+    test_suite(&suite)?;
+  } else {
+    test_suite("tests/JSON-Schema-Test-Suite")?;
+    test_suite("tests/Extra-Test-Suite")?;
+  }
+  Ok(())
+}
+
+fn test_suite(suite: &str) -> Result<(), Box<dyn Error>> {
+  if !Path::new(suite).exists() {
+    Err(format!("test suite {suite} does not exist"))?;
+  }
+  test_dir(suite, "draft4", Draft::V4)?;
+  test_dir(suite, "draft6", Draft::V6)?;
+  test_dir(suite, "draft7", Draft::V7)?;
+  test_dir(suite, "draft2019-09", Draft::V2019_09)?;
+  test_dir(suite, "draft2020-12", Draft::V2020_12)?;
+  Ok(())
+}
+
+fn test_dir(suite: &str, path: &str, draft: Draft) -> Result<(), Box<dyn Error>> {
+  let prefix = Path::new(suite).join("tests");
+  let dir = prefix.join(path);
+  if !dir.is_dir() {
+    return Ok(());
+  }
+  for entry in dir.read_dir()? {
+    let entry = entry?;
+    let file_type = entry.file_type()?;
+    let tmp_entry_path = entry.path();
+    let entry_path = tmp_entry_path.strip_prefix(&prefix)?.to_str().unwrap();
+    if file_type.is_file() {
+      if !SKIP.iter().any(|n| OsStr::new(n) == entry.file_name()) {
+        test_file(suite, entry_path, draft)?;
+      }
+    } else if file_type.is_dir() {
+      test_dir(suite, entry_path, draft)?;
+    }
+  }
+  Ok(())
+}
+
+fn test_file(suite: &str, path: &str, draft: Draft) -> Result<(), Box<dyn Error>> {
+  println!("FILE: {path}");
+  let path = Path::new(suite).join("tests").join(path);
+  let optional = path.components().any(|comp| comp.as_os_str() == "optional");
+  let file = File::open(path)?;
+
+  let url = "http://testsuite.com/schema.json";
+  let groups: Vec<Group> = serde_json::from_reader(file)?;
+  for group in groups {
+    println!("{}", group.description);
+    let mut schemas = Schemas::default();
+    let mut compiler = Compiler::default();
+    compiler.set_default_draft(draft);
+    if optional {
+      compiler.enable_format_assertions();
+      compiler.enable_content_assertions();
+    }
+    compiler.use_loader(Box::new(RemotesLoader(suite.to_owned())));
+    compiler.add_resource(url, group.schema)?;
+    let sch_index = compiler.compile(url, &mut schemas)?;
+    for test in group.tests {
+      println!("  {}", test.description);
+      let result = schemas.validate(&test.data, sch_index, None);
+      if let Err(e) = &result {
+        for line in format!("{e}").lines() {
+          println!("    {line}");
+        }
+        for line in format!("{e:#}").lines() {
+          println!("    {line}");
+        }
+      }
+      assert_eq!(result.is_ok(), test.valid);
+    }
+  }
+  Ok(())
+}
+
+struct RemotesLoader(String);
+impl UrlLoader for RemotesLoader {
+  fn load(&self, url: &str) -> Result<Value, Box<dyn std::error::Error>> {
+    // remotes folder --
+    if let Some(path) = url.strip_prefix("http://localhost:1234/") {
+      let path = Path::new(&self.0).join("remotes").join(path);
+      let file = File::open(path)?;
+      let json: Value = serde_json::from_reader(file)?;
+      return Ok(json);
+    }
+    Err("no internet")?
+  }
+}

version

@@ -1 +1 @@
-1.0.18
+1.0.39