Can't made authenticated requests with Mocha and Supertest - node.js

Question

I'm trying to test an API with Mocha and Supertest without lucky to make it work.
I have the following code:
var supertest = require('supertest');
describe('Routing', function() {
var url = 'http://example.com';
var server = supertest.agent(url);
var credentials = {
user: 'username',
pass: 'password'
};
describe('Login', function() {
it('should login ok given valid credentials', function(done) {
server
.post('/login.php')
.send(credentials)
.end(function(err, res) {
if (err) {
throw err;
}
server.saveCookies(res);
done();
});
});
it('should correctly make an authenticated request', function(done){
server
.get('/api/me/accounts?_=1449865354112')
.end(function(err,res) {
if (err) {
throw err;
}
res.status.should.be.equal(200);
done();
});
});
});
});
The login request works fine, I get authenticated. The second call throws a 401 status.
I read the documentation but I can't make it work.
What is wrong?
thanks!
UPDATE:
I finally get authenticated by sending the params using .field('user', 'myUsername') and .field('pass', 'myPassword').
Also I have to persist the cookie between calls:
cookie = res.headers['set-cookie']; when I get authenticated, and .set('cookie', cookie) in the next requests.

Answer 1

.send() is for your data. .auth() is for your credentials. Try:
it('should login ok given valid credentials', function(done) {
server
.post('/login.php')
.auth(credentials)
.send({"some": "value"})
.expect(200)
.end(function(err, res) {
if (err) {
done(error);
}
server.saveCookies(res);
done();
});
});
See http://visionmedia.github.io/superagent/docs/test.html for a bit more information on supertest.

Answer 2

That is because the session (cookie) is not persisted between your two tests.
First you should do the two calls inside the same test.
Second i remember that i have used superagent to persist the session between two calls to the same server. But it seems that supertest now expose the agent to persist the session.
var supertest = require('supertest');
var app = express();
var agent = supertest.agent(app);
// then you can persist cookie
agent
.post('/login.php')
.auth(credentials)
...
edit :
here is an example of how i have used superagent for tests :
var request = require('superagent');
var postData= {
email: 'john#test.com',
password: 'test'
};
var user1 = request.agent();
user1.post('http://localhost:3000/user/login')
.send(postData)
.end(function (err, res) {
expect(err).to.not.exist;
expect(res.status).to.equal(200);
var result = res.body;
expect(result.data.message).to.equal('Login successful');
user1.get('http://localhost:3000/user')
.end(function (err, res) {
expect(err).to.not.exist;
expect(res.status).to.equal(200);
var result = res.body;
expect(result.data.email).to.equal('john#test.com');
done();
});
});