Schema is already registered

[RonB]

Hi,

I am running into a problem where a schema is already registered. I am using an apiMap object that contains a list of api's to be registered in the openapi document.

The parameters, body or response refer to zod schemas that can be used multiple times, ie user/read and user.save return the same schema. I want to use the reference method but if i transform every schema like so:

const setSchema = (zod_schema: z.ZodTypeAny) {
      return zod_schema.openapi({
		description: name,
		ref: `${name}`
	})
}	

and the snippet to generate the document

                for (const [name, api] of apiMap.entries()) {
   		paths[api.path!] = {}
   		let path: ZodOpenApiOperationObject = {
   			operationId: api.path,
   			summary: api.description,
   			responses: {
   				'200': {
   					description: 'Successful operation',
   					content: {
   						'application/json': {
   							schema: setSchema(api.response)
   						},
   					},
   				},
   			}
   		};
   		// we need to update the schemas for all parameter types
   		// and add the openapi extension
   		let parameters: any = {}
   		if (api.params) {
   			const paramTypes: Array<'query' | 'path' | 'header'> = ['query', 'path', 'header'];
   			paramTypes.forEach(paramType => {
   				if (api.params![paramType]) {
   					Object.entries(api.params![paramType]).forEach(([key, param]) => {
   						api.params![paramType]![key] = setSchema(param);
   					});
   					parameters[paramType] = z.object(api.params![paramType]);
   				}
   			});
   			console.log(parameters)
   			path.requestParams = parameters;
   		}
   		if (api.body) {
   			path.requestBody = {
   				content: {
   					'application/json': {
   						schema: setSchema(api.body)
   					},
   				}
   			}
   		}
   		paths[api.path!][api.method] = path
   	}

   	// Initialize the OpenAPI document
   	const document = createDocument({
   		openapi: '3.1.0',
   		info: {
   			title: 'Flying-Pillow Public API',
   			description: 'Open API definition for the Flying-Pillow system',
   			termsOfService: 'The API is FlyingPillow proprietary. Used at your own risk',
   			version: '1.0.0'
   		},
   		servers: [
   			{
   				url: host,
   				description: 'Public API endpoint for the Flying-Pillow services'
   			}
   		],
   		paths
   	});

An entry in the apiMap:

ApiMap.set('/api/openapi', {
	path: '/api/openapi',
	params: {
		query: {
			format: z.enum(['yaml', 'json']).default('json').describe('format')
		}
	},
	description: 'OpenAPI JSON Definition',
	method: 'get',
	fn: openapi,
	response: z.object({ openapi: z.string() }).describe('Open API formatted JSON/YAML definition'),
	tags: ['system'],
	access: ['anonymous']
});

And the error

Error generating OpenAPI document: Error: Schema "format" is already registered
    at /flying-pillow/node_modules/.pnpm/[email protected][email protected]/node_modules/zod-openapi/dist/components.chunk.mjs:2264:15

I hope i am not overcomplicating things here, but i use a typescript decorator to generate the ApiMap that automatically registers an entry in the ApiMap.

Maybe i should register the different schema's manually? I have tried that but run into the same problem.

Thanks for your response, Ronald

[samchungy]

When you use the .openapi() method, it returns a new instance of your schema. This library will store that specific instance and when it runs into it, it will generate a reference instead.

eg.

const AString = z.string();

const ARegisteredString = AString().openapi({ ref: 'registered' });

// If you were to try and register AString again:

const BRegisteredString = AString().openapi({ ref: 'registered' });

ARegisteredString === BRegisteredString // false;

// Instead, you want to try and pass around `ARegisteredString`

const OtherSchema = z.object( { a: ARegisteredString });

[RonB]

Thanks, it is clear now.