How can I use Supertest for advanced API testing?

How can I use Supertest for advanced API testing?

Supertest is a great tool for testing HTTP servers in Node.js. What specific features are you interested in?

I want to test authentication and error handling.

You can use Supertest to send requests with authentication headers. For error handling, you can assert the response status and body.

Can you show me an example of testing a login endpoint?

Sure! Here's a basic example:

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

describe('POST /login', () => {
  it('responds with json', async () => {
    const response = await request(app)
      .post('/login')
      .send({ username: 'user', password: 'pass' })
      .expect('Content-Type', /json/)
      .expect(200);

    expect(response.body).toHaveProperty('token');
  });
});

That looks great! How do I handle different response statuses?

You can chain .expect() methods to check for different status codes. For example, use .expect(401) for unauthorized responses.