adobe · brenthosie · Jun 11, 2026
diff --git a/OpenJSFoundation/draft04/official-ajv-draft-04-meta-schema/README.md b/OpenJSFoundation/draft04/official-ajv-draft-04-meta-schema/README.md
@@ -0,0 +1,19 @@
+# official-ajv-draft-04-meta-schema
+
+## What this file is
+
+`official-ajv-draft-04-meta-schema.json` is the canonical JSON Schema draft-04 meta-schema — the schema that describes what a valid draft-04 JSON Schema looks like. It is sourced from the `ajv-draft-04` npm package (`node_modules/ajv-draft-04/dist/refs/json-schema-draft-04.json`), which itself mirrors the official specification document published by the JSON Schema organization.
+
+## Why it exists here
+
+`@adobe/reactor-validator` uses AJV v8 to validate Tags extension descriptors against the turbine platform schemas (`@adobe/reactor-turbine-schemas`). Those schemas declare `"$schema": "http://json-schema.org/draft-04/schema#"`, meaning they are draft-04 JSON Schemas.
+
+AJV v8 ships meta-schemas for draft-06, draft-07, draft 2019-09, and draft 2020-12 — but not draft-04. Previously, the `ajv-draft-04` package was used as a dependency to supply both the draft-04 vocabulary and this meta-schema. That package declares `ajv@^8` as an optional peer dependency, which causes a runtime resolution failure for downstream consumers: npm nests `ajv@8` under this package's own `node_modules`, while `ajv-draft-04` gets hoisted to the consumer's top-level `node_modules` and resolves `require('ajv/dist/core')` against whatever AJV version the consumer has installed — which may be v6.
+
+To eliminate that broken dependency chain, `ajv-draft-04` was removed and AJV v8 is now configured directly. This file provides the draft-04 meta-schema so AJV can validate that the turbine platform schemas are well-formed draft-04 schemas at compile time, preserving the same correctness guarantees as before.
+
+## Source
+
+- npm package: `ajv-draft-04` (any version)
+- path within package: `dist/refs/json-schema-draft-04.json`
+- upstream specification: http://json-schema.org/draft-04/schema
diff --git a/...undation/draft04/official-ajv-draft-04-meta-schema/official-ajv-draft-04-meta-schema.json b/...undation/draft04/official-ajv-draft-04-meta-schema/official-ajv-draft-04-meta-schema.json
@@ -0,0 +1,138 @@
+{
+  "id": "http://json-schema.org/draft-04/schema#",
+  "$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": "uri"
+    },
+    "$schema": {
+      "type": "string",
+      "format": "uri"
+    },
+    "title": {
+      "type": "string"
+    },
+    "description": {
+      "type": "string"
+    },
+    "default": {},
+    "multipleOf": {
+      "type": "number",
+      "minimum": 0,
+      "exclusiveMinimum": true
+    },
+    "maximum": {
+      "type": "number"
+    },
+    "exclusiveMaximum": {
+      "type": "boolean",
+      "default": false
+    },
+    "minimum": {
+      "type": "number"
+    },
+    "exclusiveMinimum": {
+      "type": "boolean",
+      "default": false
+    },
+    "maxLength": {"$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": "#"}
+  },
+  "dependencies": {
+    "exclusiveMaximum": ["maximum"],
+    "exclusiveMinimum": ["minimum"]
+  },
+  "default": {}
+}
diff --git a/lib/createDraft4Ajv.js b/lib/createDraft4Ajv.js
@@ -0,0 +1,133 @@
+/***************************************************************************************
+ * (c) 2017 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ ****************************************************************************************/
+
+// Factory that creates an AJV v8 instance configured for JSON Schema draft-04.
+//
+// AJV v8 speaks draft-07 natively and does not ship a draft-04 meta-schema. This module
+// replicates what the ajv-draft-04 package provided, using only ajv's own internal modules,
+// so downstream consumers are not exposed to ajv-draft-04's broken optional peer-dependency
+// chain (see: https://github.com/adobe/reactor-validator/issues/XX).
+
+'use strict';
+var _ajvCore = require('ajv/dist/core');
+var AjvCore = _ajvCore.default;
+var _ = _ajvCore._;
+var str = _ajvCore.str;
+var ops = require('ajv/dist/compile/codegen').operators;
+var addAJVFormats = require('ajv-formats');
+var draft4MetaSchema = require('../OpenJSFoundation/draft04/official-ajv-draft-04-meta-schema/official-ajv-draft-04-meta-schema.json');
+
+var DRAFT4_META_SCHEMA_ID = 'http://json-schema.org/draft-04/schema';
+
+// JSON Schema draft-04 and draft-07 express "exclusive" range limits differently:
+//
+//   draft-04: two keywords — a numeric "minimum" plus a boolean flag "exclusiveMinimum: true"
+//             e.g. { "minimum": 0, "exclusiveMinimum": true } means value must be > 0
+//
+//   draft-07: one keyword — "exclusiveMinimum" is itself the numeric limit
+//             e.g. { "exclusiveMinimum": 0 } means value must be > 0
+//
+// AJV v8 speaks draft-07 natively, so it expects exclusiveMinimum/exclusiveMaximum to always
+// be numbers. The draft-04 meta-schema we register (so AJV can validate that the turbine platform
+// schemas are well-formed draft-04) uses the boolean flag style internally. Without custom
+// handlers, AJV v8 throws "exclusiveMinimum value must be [number]" when it tries to compile
+// that meta-schema.
+//
+// limitNumberDraft4 replaces AJV v8's built-in limitNumber. It handles "minimum"/"maximum" as
+// numeric keywords but peeks at the parent schema for a boolean exclusiveMinimum/exclusiveMaximum
+// flag, switching between strict (>) and non-strict (>=) comparisons accordingly.
+//
+// limitNumberExclusiveDraft4 registers "exclusiveMinimum"/"exclusiveMaximum" as valid boolean
+// keywords so AJV does not reject them. It generates no data-validation code — the actual
+// comparison logic lives in limitNumberDraft4 above.
+var LIMIT_KWDS = {
+  maximum: {
+    exclusive: 'exclusiveMaximum',
+    ops: [
+      { okStr: '<=', ok: ops.LTE, fail: ops.GT },
+      { okStr: '<',  ok: ops.LT,  fail: ops.GTE },
+    ],
+  },
+  minimum: {
+    exclusive: 'exclusiveMinimum',
+    ops: [
+      { okStr: '>=', ok: ops.GTE, fail: ops.LT },
+      { okStr: '>',  ok: ops.GT,  fail: ops.LTE },
+    ],
+  },
+};
+
+function kwdOp(cxt) {
+  var kwd = LIMIT_KWDS[cxt.keyword];
+  var opsIdx = (cxt.parentSchema && cxt.parentSchema[kwd.exclusive]) ? 1 : 0;
+  return kwd.ops[opsIdx];
+}
+
+var limitNumberDraft4 = {
+  keyword: Object.keys(LIMIT_KWDS),
+  type: 'number',
+  schemaType: 'number',
+  $data: true,
+  error: {
+    message: function(cxt) { return str`must be ${kwdOp(cxt).okStr} ${cxt.schemaCode}`; },
+    params:  function(cxt) { return _`{comparison: ${kwdOp(cxt).okStr}, limit: ${cxt.schemaCode}}`; },
+  },
+  code: function(cxt) {
+    cxt.fail$data(_`${cxt.data} ${kwdOp(cxt).fail} ${cxt.schemaCode} || isNaN(${cxt.data})`);
+  },
+};
+
+var limitNumberExclusiveDraft4 = {
+  keyword: ['exclusiveMaximum', 'exclusiveMinimum'],
+  type: 'number',
+  schemaType: 'boolean',
+  code: function(cxt) {
+    var paired = { exclusiveMaximum: 'maximum', exclusiveMinimum: 'minimum' };
+    if (cxt.parentSchema[paired[cxt.keyword]] === undefined) {
+      throw new Error(cxt.keyword + ' can only be used with ' + paired[cxt.keyword]);
+    }
+  },
+};
+
+var draft4CoreVocab = [
+  '$schema', 'id', '$defs', '$comment', 'definitions',
+  require('ajv/dist/vocabularies/core/ref').default,
+];
+
+var draft4ValidationVocab = [
+  limitNumberDraft4,
+  limitNumberExclusiveDraft4,
+  require('ajv/dist/vocabularies/validation/multipleOf').default,
+  require('ajv/dist/vocabularies/validation/limitLength').default,
+  require('ajv/dist/vocabularies/validation/pattern').default,
+  require('ajv/dist/vocabularies/validation/limitProperties').default,
+  require('ajv/dist/vocabularies/validation/required').default,
+  require('ajv/dist/vocabularies/validation/limitItems').default,
+  require('ajv/dist/vocabularies/validation/uniqueItems').default,
+  { keyword: 'type', schemaType: ['string', 'array'] },
+  { keyword: 'nullable', schemaType: 'boolean' },
+  require('ajv/dist/vocabularies/validation/const').default,
+  require('ajv/dist/vocabularies/validation/enum').default,
+];
+
+module.exports = function createDraft4Ajv() {
+  var ajv = new AjvCore({ schemaId: 'id', strict: false, defaultMeta: DRAFT4_META_SCHEMA_ID });
+  ajv.addVocabulary(draft4CoreVocab);
+  ajv.addVocabulary(draft4ValidationVocab);
+  ajv.addVocabulary(require('ajv/dist/vocabularies/applicator').default());
+  ajv.addVocabulary(require('ajv/dist/vocabularies/format').default);
+  ajv.addVocabulary(['title', 'description', 'default']);
+  ajv.addMetaSchema(draft4MetaSchema, DRAFT4_META_SCHEMA_ID, false);
+  ajv.refs['http://json-schema.org/schema'] = DRAFT4_META_SCHEMA_ID;
+  addAJVFormats(ajv);
+  return ajv;
+};
diff --git a/lib/validateSchema.js b/lib/validateSchema.js
@@ -15,15 +15,16 @@
 // Returns undefined if valid, or an error string if not.
 
 'use strict';
-var Ajv = require("ajv-draft-04");
-var addAJVFormats = require("ajv-formats");
+var createDraft4Ajv = require('./createDraft4Ajv');
 
 var schemas = {
   web: require('@adobe/reactor-turbine-schemas/schemas/extension-package-web.json'),
   edge: require('@adobe/reactor-turbine-schemas/schemas/extension-package-edge.json'),
   mobile: require('@adobe/reactor-turbine-schemas/schemas/extension-package-mobile.json')
 };
 
+var ajv = createDraft4Ajv();
+
 var validateJsonStructure = function(extensionDescriptor) {
   var platform = extensionDescriptor.platform;
   if (!platform) {
@@ -33,8 +34,6 @@ var validateJsonStructure = function(extensionDescriptor) {
   if (!extensionDescriptorSchema) {
     return 'unknown platform "' + platform + '".';
   }
-  var ajv = new Ajv({ schemaId: 'auto', strict: false });
-  addAJVFormats(ajv);
   if (!ajv.validate(extensionDescriptorSchema, extensionDescriptor)) {
     return ajv.errorsText();
   }