Support draft-04 schemas

package.json

@@ -27,6 +27,7 @@
   },
   "dependencies": {
     "ajv": "^8.17.1",
+    "ajv-draft-04": "^1.0.0",
     "lodash": "4.17.21",
     "prettier": "^3.5.0",
     "request-light": "^0.5.7",

src/languageservice/services/yamlSchemaService.ts

@@ -28,9 +28,11 @@ import { JSONSchemaDescriptionExt } from '../../requestTypes';
 import { SchemaVersions } from '../yamlTypes';
 
 import Ajv, { DefinedError } from 'ajv';
+import Ajv4 from 'ajv-draft-04';
 import { getSchemaTitle } from '../utils/schemaUtils';
 
 const ajv = new Ajv();
+const ajv4 = new Ajv4();
 
 const localize = nls.loadMessageBundle();
 
@@ -39,6 +41,11 @@ const localize = nls.loadMessageBundle();
 const jsonSchema07 = require('ajv/dist/refs/json-schema-draft-07.json');
 const schema07Validator = ajv.compile(jsonSchema07);
 
+// eslint-disable-next-line @typescript-eslint/no-var-requires
+const jsonSchema04 = require('ajv-draft-04/dist/refs/json-schema-draft-04.json');
+const schema04Validator = ajv4.compile(jsonSchema04);
+const SCHEMA_04_URI_WITH_HTTPS = ajv4.defaultMeta().replace('http://', 'https://');
+
 export declare type CustomSchemaProvider = (uri: string) => Promise<string | string[]>;
 
 export enum MODIFICATION_ACTIONS {
@@ -164,9 +171,13 @@ export class YAMLSchemaService extends JSONSchemaService {
     let schema: JSONSchema = schemaToResolve.schema;
     const contextService = this.contextService;
 
-    if (!schema07Validator(schema)) {
+    const validator =
+      this.normalizeId(schema.$schema) === ajv4.defaultMeta() || this.normalizeId(schema.$schema) === SCHEMA_04_URI_WITH_HTTPS
+        ? schema04Validator
+        : schema07Validator;
+    if (!validator(schema)) {
       const errs: string[] = [];
-      for (const err of schema07Validator.errors as DefinedError[]) {
+      for (const err of validator.errors as DefinedError[]) {
         errs.push(`${err.instancePath} : ${err.message}`);
       }
       resolveErrors.push(`Schema '${getSchemaTitle(schemaToResolve.schema, schemaURL)}' is not valid:\n${errs.join('\n')}`);

test/schemaValidation.test.ts

@@ -2151,4 +2151,66 @@ obj:
     result = await parseSetup(content);
     expect(result.length).to.eq(0);
   });
+
+  it('draft-04 schema', async () => {
+    const schema: JSONSchema = {
+      $schema: 'http://json-schema.org/draft-04/schema#',
+      type: 'object',
+      properties: {
+        myProperty: {
+          $ref: '#/definitions/Interface%3Ctype%3E',
+        },
+      },
+      definitions: {
+        'Interface<type>': {
+          type: 'object',
+          properties: {
+            foo: {
+              type: 'string',
+            },
+            multipleOf: {
+              type: 'number',
+              minimum: 0,
+              exclusiveMinimum: true,
+            },
+          },
+        },
+      },
+    };
+    schemaProvider.addSchema(SCHEMA_ID, schema);
+    const content = `myProperty:\n  foo: bar\n  multipleOf: 1`;
+    const result = await parseSetup(content);
+    assert.equal(result.length, 0);
+  });
+
+  it('draft-04 schema with https in metaschema URI', async () => {
+    const schema: JSONSchema = {
+      $schema: 'https://json-schema.org/draft-04/schema#',
+      type: 'object',
+      properties: {
+        myProperty: {
+          $ref: '#/definitions/Interface%3Ctype%3E',
+        },
+      },
+      definitions: {
+        'Interface<type>': {
+          type: 'object',
+          properties: {
+            foo: {
+              type: 'string',
+            },
+            multipleOf: {
+              type: 'number',
+              minimum: 0,
+              exclusiveMinimum: true,
+            },
+          },
+        },
+      },
+    };
+    schemaProvider.addSchema(SCHEMA_ID, schema);
+    const content = `myProperty:\n  foo: bar\n  multipleOf: 1`;
+    const result = await parseSetup(content);
+    assert.equal(result.length, 0);
+  });
 });

yarn.lock

@@ -681,6 +681,11 @@ aggregate-error@^3.0.0:
     clean-stack "^2.0.0"
     indent-string "^4.0.0"
 
+ajv-draft-04@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/ajv-draft-04/-/ajv-draft-04-1.0.0.tgz#3b64761b268ba0b9e668f0b41ba53fce0ad77fc8"
+  integrity sha512-mv00Te6nmYbRp5DCwclxtt7yV/joXJPGS7nM+97GdxvuttCOfgI3K4U25zboyeX0O+myI8ERluxQe5wljMmVIw==
+
 ajv@^6.10.0, ajv@^6.12.3, ajv@^6.12.4:
   version "6.12.6"
   resolved "https://registry.npmjs.org/ajv/-/ajv-6.12.6.tgz"