fix: root level reference are not handled for JSON Schema

src/processors/JsonSchemaInputProcessor.ts

@@ -63,7 +63,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
  const inputModel = new InputMetaModel();
  inputModel.originalInput = input;
  input = JsonSchemaInputProcessor.reflectSchemaNames(input, {}, 'root', true) as Record<string, any>;
- await this.dereferenceInputs(input);
+ input = await this.dereferenceInputs(input);
  const parsedSchema = Draft7Schema.toSchema(input);
  const newCommonModel = JsonSchemaInputProcessor.convertSchemaToCommonModel(parsedSchema);
  const metaModel = convertToMetaModel(newCommonModel);
@@ -82,7 +82,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
  const inputModel = new InputMetaModel();
  inputModel.originalInput = input;
  input = JsonSchemaInputProcessor.reflectSchemaNames(input, {}, 'root', true) as Record<string, any>;
- await this.dereferenceInputs(input);
+ input = await this.dereferenceInputs(input);
  const parsedSchema = Draft4Schema.toSchema(input);
  const newCommonModel = JsonSchemaInputProcessor.convertSchemaToCommonModel(parsedSchema);
  const metaModel = convertToMetaModel(newCommonModel);
@@ -101,7 +101,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
  const inputModel = new InputMetaModel();
  inputModel.originalInput = input;
  input = JsonSchemaInputProcessor.reflectSchemaNames(input, {}, 'root', true) as Record<string, any>;
- await this.dereferenceInputs(input);
+ input = await this.dereferenceInputs(input);
  const parsedSchema = Draft6Schema.toSchema(input);
  const newCommonModel = JsonSchemaInputProcessor.convertSchemaToCommonModel(parsedSchema);
  const metaModel = convertToMetaModel(newCommonModel);
@@ -110,7 +110,41 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
  return inputModel;
  }
 
- private async dereferenceInputs(input: Record<string, any>) {
+ /**
+ * This is a hotfix and really only a partial solution as it does not cover all cases.
+ * 
+ * But it's the best we can do until we find or build a better library to handle references.
+ */
+ public handleRootReference(input: Record<string, any>): Record<string, any> {
+ //Because of https:/APIDevTools/json-schema-ref-parser/issues/201 the tool cannot handle root references.
+ //This really is a bad patch to fix an underlying problem, but until a full library is available, this is best we can do.
+ const hasRootRef = input.$ref !== undefined;
+ if (hasRootRef) {
+ Logger.warn('Found a root $ref, which is not fully supported in Modelina, trying to do what I can with it...');
+ //When we encounter it, manually try to resolve the reference in the definitions section
+ const hasDefinitionSection = input.definitions !== undefined;
+ if (hasDefinitionSection) {
+ const definitionLink = '#/definitions/';
+ const referenceLink = input.$ref.slice(0, definitionLink.length);
+ const referenceIsLocal = referenceLink === definitionLink;
+ if (referenceIsLocal) {
+ const definitionName = input.$ref.slice(definitionLink.length);
+ const definition = input.definitions[String(definitionName)];
+ const definitionExist = definition !== undefined;
+ if (definitionExist) {
+ delete input.$ref;
+ return {...definition, ...input};
+ }
+ }
+ }
+ //All other unhandled cases, means we cannot handle this input
+ throw new Error('Cannot handle input, because it has a root `$ref`, please manually resolve the first reference.'); 
+ }
+ return input;
+ }
+
+ public async dereferenceInputs(input: Record<string, any>): Promise<Record<string, any>> {
+ input = this.handleRootReference(input);
  Logger.debug('Dereferencing all $ref instances');
  const refParser = new $RefParser;
  // eslint-disable-next-line no-undef
@@ -128,6 +162,7 @@ export class JsonSchemaInputProcessor extends AbstractInputProcessor {
  throw new Error(errorMessage);
  }
  Logger.debug('Successfully dereferenced all $ref instances from input.', input);
+ return input;
  }
 
  /**

test/processors/JsonSchemaInputProcessor.spec.ts

@@ -138,6 +138,38 @@ describe('JsonSchemaInputProcessor', () => {
  });
  });
 
+ describe('dereferenceInputs()', () => {
+ test('should handle root $ref', () => {
+ const processor = new JsonSchemaInputProcessor();
+ const schema = {
+ definitions: {
+ root: {
+ type: 'string'
+ }
+ },
+ $ref: '#/definitions/root'
+ };
+ const dereferencedSchema = processor.handleRootReference(schema);
+ expect(dereferencedSchema).toEqual({definitions: {root: {type: 'string'}}, type: 'string'});
+ });
+ test('should handle root $ref that cannot be processed', () => {
+ const processor = new JsonSchemaInputProcessor();
+ const schema = {
+ definitions: {
+ root: {
+ definitions: {
+ innerRoot: {
+ type: 'string'
+ }
+ }
+ }
+ },
+ $ref: '#/definitions/root/definitions/innerRoot'
+ };
+ expect(() => processor.handleRootReference(schema)).toThrowError('Cannot handle input, because it has a root `$ref`, please manually resolve the first reference.');
+ });
+ });
+
  describe('convertSchemaToCommonModel()', () => {
  test('Should ignore models which does not have $id', () => {
  const model = new CommonModel();