socket.io-client Jest testing inconsistent results - sockets

Question

I am writing some end-to-end test cases to test socket connections in my app. I expect receiving socket events after specific rest API requests. For instance, after hitting: /api/v1/[createTag], I expect receiving createTag event to be captured by socket.io-client. The issue is that, it is very inconsistently passing, and sometimes failing, with good rest API requests. The reason to fail is that done() event inside socket.on('createTag' ... is never called, so it gets timeout. On browser, currently all the API endpoints and sockets seem to be working fine. Is there a specific configuration that I might be missing in order to test socket.io-client within Node.js environment and Jest?
Below is my test cases, and thanks a lot in advance:
describe('Socket integration tests: ', () => {
beforeAll(async done => {
await apiInit();
const result = await requests.userSignIn(TEST_MAIL, TEST_PASSWORD);
TEST_USER = result.user;
SESSION = result.user.session;
console.log('Test user authenticated succesfully.');
done();
});
beforeEach(done => {
socket = io(config.socket_host, { forceNew: true })
socket.on('connect', () => {
console.log('Socket connection succesful.');
socket.emit('session', { data: SESSION }, (r) => {
console.log('Socket session successful.');
done();
});
});
})
test('Receiving createTag socket event?', async(done) => {
console.log('API request on createTag');
const response = await Requester.post(...);
console.log('API response on createTag', response);
socket.on('createTag', result => {
console.log('createTag socket event succesful.');
createdTagXid = result.data.xid;
done();
})
});
afterEach(done => {
if(socket.connected) {
console.log('disconnecting.');
socket.disconnect();
} else {
console.log('no connection to break');
}
done();
})
}

Answer 1

Basically, setting event handles after async API calls seems to be the issue. So I should have first set the socket.on( ... and then call rest API.