API Unit Testing Jest

API Unit Testing with Jest (TMET)

Use this skill to

• Add regression coverage for route validation, status codes, payloads, and queue orchestration.
• Test model/helper behavior in isolation with mocked filesystem, network, or Browserless boundaries.
• Keep backend changes aligned with the existing Jest suite instead of inventing a new test harness.

Test layout

• tests/routes/*
• tests/models/*
• tests/helpers/*
• tests/integration/routes.test.js
• Shared helpers: tests/setup.js, tests/fixtures.js
• Config: jest.config.js

Existing patterns to reuse

• Use jest.unstable_mockModule(...) for ESM dependency mocking.
• Use createMockRequest(...) and createMockResponse() from tests/setup.js for route handler tests.
• Use suppressConsole() in suites that intentionally exercise error paths or noisy progress logging.

Workflow

1. Start from the nearest existing test file for the touched route, model, or helper.
2. Cover one meaningful behavior at a time: validation, success path, queue callback, or artifact-writing side effect.
3. Mock unstable boundaries explicitly: filesystem, fetch, Browserless, or Moodle upload helpers.
4. Run the narrowest relevant test file first, then widen only if the change crosses module boundaries.

Commands

npm test -- tests/routes/moodleRoute.test.js
npm test -- tests/models/MoodleModel.test.js
docker compose exec node npm test -- tests/integration/routes.test.js

Out of scope

• Introducing new test frameworks.
• Browser E2E infrastructure that does not exist in this repository.

Source: werlang/tmet — distributed by TomeVault.