TypeScript Query Operations

In this section, we'll learn how to implement a Query Operation using TypeScript. We'll create a get operation that returns a user by its ID.

Import the createOperation function and the z object from the wundergraph.factory module. It's important that the result of createOperation is exported as the default export of the file.

The route of the operation is derived from the file path. In this case, the file is located at .wundergraph/operations/users/get.ts, so the route of the operation is /operations/users/get.

// .wundergraph/operations/users/get.ts
import { createOperation, z } from '../../generated/wundergraph.factory';

export default createOperation.query({
  // by specifying the input schema, we're automatically creating a JSON Schema for input validation
  input: z.object({
    id: z.string(),
  }),
  handler: async ({ input }) => {
    // here you can do whatever you want, like calling an external API, a database, or other operations via the internalClient
    return {
      id: input.id,
      name: 'Jens',
      bio: 'Founder of WunderGraph',
    };
  },
});

Let's call this operation using curl:

curl http://localhost:9991/operations/users/get?id=1

The result should be:

{
  "data": {
    "id": "1",
    "name": "Jens",
    "bio": "Founder of WunderGraph"
  }
}