Unit testing an endpoint controller with Node and Rewire - node.js

Question

I am using rewire to test my node controllers. I have the following endpoint that uses request to GET some data.
exports.myGetEndpoint = function(req, res) {
return request.get({
url: 'http://baseURL/api/myGetEndpoint',
headers: {
authorization: { //etc }
},
json: true
})
.then(function(data) {
res.status(200).json(data.objects);
});
};
I want to test that when I call the get method from the controller, that request gets called with the correct arguments, but I'm lost on how to either 'stub' or 'spy' on request.
var Promise = require('bluebird');
var rewire = require('rewire');
var controller = rewire('../../controllers/myGetEndpoint.js');
var request = {
get: sinon.stub()
};
// Use rewire to mock dependencies
controller.__set__({
request: request
});
describe('myGetEndpoint', function() {
var json;
var req;
var res;
beforeEach(function(done) {
json = sinon.spy();
req = { headers: {} };
res = {
status: sinon.stub().returns({
json: json
})
};
controller.myGetEndpoint(req, res).then(function() {
done();
});
});
it('should call the correct request arguments', function() {
// lost
});
});

Answer 1

I am going to modify a bit your source code to use just a callback instead of a promise. I need to investigate how to stub a promise with sinon but you can get an idea on how it can be tested with a simple callback:
exports.myGetEndpoint = function(req, res) {
return request.get({
url: 'http://baseURL/api/myGetEndpoint',
headers: {
authorization: { //etc }
},
json: true
}, function (error, response, body) {
res.status(200).json(response.objects);
});
};
You should not call the controller in the beforeEach but you must call it inside the test case. The beforeEach normally is used to do the initializations before the test case:
var expect = require('chai').expect;
var Promise = require('bluebird');
var rewire = require('rewire');
var controller = rewire('../../controllers/myGetEndpoint.js');
var request = {
get: sinon.stub()
};
// Use rewire to mock dependencies
controller.__set__({
request: request
});
describe('myGetEndpoint', function() {
var status;
var json;
var req;
var res;
beforeEach(function(done) {
json = sinon.spy();
status = sinon.stub();
req = { headers: {} };
res = {
status: status.returns({
json: json
})
};
});
it('should call the correct response arguments', function(done) {
var response = {objects: ['objects', 'objects']}
request.get.yields(null, response);
controller.myGetEndpoint(req, res);
expect(status.calledWith(200)).to.equal(true);
expect(json.calledWith(response.objects)).to.equal(true);
});
});
P.S.: I didn't actually try to run it, so maybe there are some typos.