What is Supertest and how do I use it for integration testing?

What is Supertest and how do I use it for integration testing?

Supertest is a popular testing library for HTTP assertions in Node.js applications. It allows you to test your APIs easily by making requests and asserting the responses.

Can you show me a basic example of how to set it up?

Sure! First, install Supertest using npm: npm install supertest --save-dev. Then, you can write a test like this:

const request = require('supertest');
const app = require('./app'); // your Express app

describe('GET /api/users', () => {
  it('responds with json', async () => {
    const response = await request(app).get('/api/users');
    expect(response.status).toBe(200);
    expect(response.body).toEqual(expect.any(Array));
  });
});

What are some common assertions I can make with Supertest?

You can assert the status code, response type, response body, and headers. For example:

• expect(response.status).toBe(200);
• expect(response.type).toBe('application/json');
• expect(response.body).toHaveProperty('id');

Can I use Supertest with other testing frameworks?

Yes, Supertest works well with popular testing frameworks like Jest, Mocha, and Chai. You can integrate it easily into your existing test setup.