How do I integration test a node express controller? - node.js

Question

We started a node application where we are going to use Express as the router. In one of our controllers, we have this defined:
var express = require('express');
var router = express.Router();
// api/products
router.get('/', function (req, res) {
res.json({ products: [] });
});
// api/products/:id
router.get('/:id', function (req, res) {
res.json({ id: req.params.id });
});
module.exports = router;
I've been trying to follow examples on how to test this and came up with:
var hippie = require('hippie');
var server = require('../controllers/products');
describe('Products Controller Tests', function () {
describe('/products endpoint', function () {
it('returns an array of products', function (done) {
hippie(server)
.json()
.get('/products')
.expectStatus(200)
.end(function (err, res, body) {
if (err) throw err;
done();
});
});
});
});
But I'm always getting the following error:
Test Name: Products Controller Tests /products endpoint returns an array of products
Test Outcome: Failed
Result StandardOutput:
not ok 1 Products Controller Tests /products endpoint returns an array of products
TypeError: Cannot read property 'apply' of undefined
at Immediate. (C:\Api\node_modules\express\lib\router\index.js:618:14)
tests 1
pass 0
fail 1
What is the best way to unit test these controllers? Is there a different library I should be using?

Answer 1

What about extracting the behaviour of your routes and unit testing that?
Something like this
var express = require('express'),
router = express.Router(),
routes = require('./routes');
router.get('/:id', routes.getId);
So that in your unit test you can have
describe('getId', function() {
var route = require('../routes').getId;
var req = // build your request object with params and so on
var res = // stub this, for example with sinon
it('whatever', function() {
route(req, res);
expect(res.send.calledOnce).to.be.true;
// and so on
});
});
Once you're covered this with unit tests (faster to run, you can hook them up on pre-commit hook), you can integration test the route, without the need to mock the underlying HTTP library, with proper calls using request for example.