Support draft-04 schemas

This helps to support the schema for openapi 3.0.0,
among others, that use an older draft of JSON schema that has some type
differences that make it incompatible with JSON schema draft 07.

See #1006 , I think the root cause for the issues that PR caused
is that we were trying to download and cache the metaschema from
the "URL" instead of using the copy that's bundled with `ajv`.

Fixes #780, Fixes #752

(and many, many duplicates we'll have to find and clean up)

Signed-off-by: David Thompson <davthomp@redhat.com>

Author: datho7561

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 +41,10 @@ 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);
+
 export declare type CustomSchemaProvider = (uri: string) => Promise<string | string[]>;
 
 export enum MODIFICATION_ACTIONS {
@@ -164,12 +170,24 @@ export class YAMLSchemaService extends JSONSchemaService {
     let schema: JSONSchema = schemaToResolve.schema;
     const contextService = this.contextService;
 
-    if (!schema07Validator(schema)) {
-      const errs: string[] = [];
-      for (const err of schema07Validator.errors as DefinedError[]) {
-        errs.push(`${err.instancePath} : ${err.message}`);
+    if (schema.$schema === 'http://json-schema.org/draft-04/schema#') {
+      if (!schema04Validator(schema)) {
+        if (!schema07Validator(schema)) {
+          const errs: string[] = [];
+          for (const err of schema07Validator.errors as DefinedError[]) {
+            errs.push(`${err.instancePath} : ${err.message}`);
+          }
+          resolveErrors.push(`Schema '${getSchemaTitle(schemaToResolve.schema, schemaURL)}' is not valid:\n${errs.join('\n')}`);
+        }
+      }
+    } else {
+      if (!schema07Validator(schema)) {
+        const errs: string[] = [];
+        for (const err of schema07Validator.errors as DefinedError[]) {
+          errs.push(`${err.instancePath} : ${err.message}`);
+        }
+        resolveErrors.push(`Schema '${getSchemaTitle(schemaToResolve.schema, schemaURL)}' is not valid:\n${errs.join('\n')}`);
       }
-      resolveErrors.push(`Schema '${getSchemaTitle(schemaToResolve.schema, schemaURL)}' is not valid:\n${errs.join('\n')}`);
     }
 
     const findSection = (schema: JSONSchema, path: string): JSONSchema => {

test/schemaValidation.test.ts

@@ -2094,4 +2094,36 @@ obj:
     const result = await parseSetup(content);
     assert.equal(result.length, 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);
+    console.log(result);
+    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"