How do you mock MySQL (with node-orm2) in Node.js/Express? - mysql

Question

I am using node.js/express with https://github.com/dresende/node-orm2 to use my MySQL database.
I am new to the node.js world and I am quite stuck so far, I don't know how to unit test (not integration test) a simple function.
Here is my server.js, loading my user model (ORM)
var express = require('express'),
orm = require('orm'),
config = require('./config/config.js'),
auth = require('./services/authentication'),
helper = require('./middlewares/helper.js'),
friends = require('./modules/friends.js');
var app = express();
app.use(orm.express('mysql://' + config.mysql.username + ':' + config.mysql.pwd + '#' + config.mysql.host + ':' + config.mysql.port + '/' + config.mysql.db, {
define: function(db, models, next) {
db.load("./models/models.js", function(err) { // loaded!
models.user = db.models.user;
});
}
}));
var middlewares = [auth.authenticate, helper.retrieveUser];
app.get('/friends', middlewares, friends.findActiveFriends);
app.listen(3000);
console.log('Listening on port 3000...');
here is the user model :
module.exports = function (db, cb) {
var User = db.define('user', {
uid : { type: 'number', rational: false, unique: true, required: true },
first_name : { type: 'text', size: 100, required: true },
last_name : { type: 'text', size: 100, required: true },
picture : { type: 'text', size: 255, required: false },
email : { type: 'text', size: 255, required: true },
creation_date : { type: 'date', time: true },
modification_date : { type: 'date', time: true }
}, {
methods: {
fullName: function () {
return this.first_name + ' ' + this.last_name;
}
},
hooks: {
beforeCreate: function (next) {
if (this.creation_date == undefined) {
this.creation_date = new Date();
}
if (this.modification_date == undefined) {
this.modification_date = new Date();
}
return next();
}
}
});
// CUSTOM FUNCTIONS
User.getByUid = function(uid, callback) {
this.find({ uid: uid }, function(err, users) {
if(err) callback(err);
if (users.length == 1) {
callback(null, users[0]);
} else {
callback('No user found with uid=' + uid);
}
});
};
User.hasMany("friends", User, {
status: { type: 'enum', values: ['pending', 'refused', 'active'] }
}, {
reverse: 'friendsrev', mergeId: 'user_id', mergeAssocId: 'friend_id'
});
return cb();
};
and here is my methods to find active friends in friends.js:
var _findActiveFriends = function(req, res) {
req.currentUser.getFriends({
status: 'active'
}, function(err, friends) {
if (err) throw err;
res.send(JSON.stringify(friends));
});
};
I would like to know how can I write a simple test (with mocha and sinon.js ?) by mocking the database connection and the request also. I need to mock the value of req.currentUser which is a user returned by the ORM in a middleware.
I just want to run unit tests and do not use a real DB or make some HTTP calls.
thanks for your help.

Answer 1

If you want to mock the req using sinon.js, you can do something like the following.
var sinon = require('sinon');
var friend = require('./friend');
it('some test', function(done) {
var req = {
currentUser: {
// Add all the properties/functions that you are concerned with here.
// and you can/should wrap them around sinon.spy().
// If you are not concerned with that function (i.e. you are not using it)
// then you can simply use sinon.stub() to return a stub function.
}
};
var res = {
send: sinon.spy(function(obj) {
assert.ok(obj); // yes object exists
done(); // end of test
};
};
var next = function() {};
friend.findActiveFriend(req, res, next);
});
This way you shouldn't be connecting to the model, which tests friend.js only.
Also, since I just noticed you are using orm.express, you may also want to simply mock req.models with the stubbed function you desire as above.