How to use “q” module for refactoring mongoose code?

Question

I\'m using mongoose to insert some data into mongodb. The code looks like:

var mongoose = require(\'mongoose\');
mongoose.connect(\'mongo://localhost/test\')         


        

Answer 1

With alternative deferred promise implementation, you may do it as following:

var mongoose = require('mongoose');
mongoose.connect('mongo://localhost/test');
var conn = mongoose.connection;

// Setup 'pinsert', promise version of 'insert' method
var promisify = require('deferred').promisify
mongoose.Collection.prototype.pinsert = promisify(mongoose.Collection.prototype.insert);

var user1, user2;
// insert users
conn.collection('users').pinsert([{/*user1*/},{/*user2*/}])
// insert channels
.then(function (users) {
  user1 = users[0]; user2 = users[1];
  return conn.collection('channels').pinsert([{userId:user1._id},{userId:user2._id}]);
})
// insert articles
.match(function (channel1, channel2) {
  return conn.collection('articles').pinsert([{userId:user1._id,channelId:channel1._id},{}]);
})
.done(function (articles) {
  // Do something with articles
}, function (err) {
   // Handle any error that might have occurred on the way
});