Testing

WunderGraph comes with builtin support for running tests against your APIs, using a our TypeScript client. Leverage our testing server implementation to set up your WunderGraph server, run your test, and finally tear everything down.

Our testing library is framework agnostic, so you can use it with your preferred test framework. We use both Jest and ava for these examples, but they should be easily adaptable to any testing framework.

Make sure your wundergraph.config.ts is set up to generate the WunderGraph testing library:

configureWunderGraphApplication({
	apis: [
        ...
	],
	server,
	operations,
  generate:{
    codeGenerators: [],
  },
});

Within a test, you can use WunderGraphTestServer.client() to retrieve a TypeScript WunderGraph client instance ready to query the server set up by the testing library.

Create your test file and import createTestServer from ./.wundergraph/generated/testing. Note that depending on your project's settings, the path might be slightly different depending on where you generate your templates.

import { createTestServer } from '../.wundergraph/generated/testing';

// Imports from Jest
import { describe, expect, test } from '@jest/globals';

We recommended creating as few testing server instances as possible and sharing them between multiple tests. These minimizes the number of times the server starts and stops, making your tests faster.

const wg = createTestServer();

Use Jest's beforeAll() and afterAll(), to set up the test server:

beforeAll(() => wg.start());
afterAll(() => wg.stop());

Finally, define your tests as Jest test functions:

test('continents', async () => {
  // Use the TypeScript client to perform queries or mutations against your API
  const result = await wg.client().query({
    operationName: 'Continents',
  })
  // Use Jest for assertions
  expect(result.data?.countries_continents.length).toBe(7)
})

test('country by code', async () => {
    // Use the TypeScript client to perform queries or mutations against your API
    const result = await wg.client().query({
      operationName: 'Countries',
      input: {
        filter: {
          code: { eq: 'AD' },
        },
      },
    })
    const andorra = result.data?.countries_countries[0]
    // Use Jest for assertions
    expect(andorra?.name).toBe('Andorra')
  })
)

If you'd like to see a full example using Jest for testing, check our simple example .

Create your test file and import createTestServer from ./.wundergraph/generated/testing. Note that depending on your project's settings, the path might be slightly different depending on where you generate your templates.

import { createTestServer } from '../.wundergraph/generated/testing';

// Imports from Ava
import { test } from 'ava';

We recommended creating as few testing server instances as possible and sharing them between multiple tests. These minimizes the number of times the server starts and stops, making your tests faster.

const wg = createTestServer();

Use Ava's test.before() and test.after() functions to setup our testing server:

test.before(() => wg.start());
test.after(() => wg.stop());

Finally, define your functions:

test('create a note', async (t) => {
  // Use the TypeScript client to perform queries or mutations against your API
  const result = await wg.client().mutate({
    operationName: 'NewNote',
    input: {
      text: 'my first note',
    },
  });
  // Use Ava for assertions
  t.falsy(result.error);
  t.not(result.data?.notes_newNote?.id ?? 0, 0, 'new note id should not be zero');
});

WunderGraph has builtin support for loading environment variables from a .env file. For testing, we recommend creating a .env.test file to set the environment variables for the test environment. This allows you to set the environment variables for the test environment without affecting your local development environment. The test server search first for a .env.test file, and if it doesn't exist, it will fall back to .env. You can also pass environment variables to the test server with the env option of the createTestServer method. None of these files should be committed to git. In your CI, you should use plain environment variables that come from your secret store.