Question

I’m trying to get my head around how mongoose uses it’s connection. At the moment I have:

// Datastore.js
var mongoose = require('mongoose'),
    conn = mongoose.createConnection();

...

conn.open(host, database, port, options, callback); // Opens connection


// Model.js
var mongoose = require('mongoose');
var Schema = new mongoose.Schema({...})
module.exports = exports = mongoose.model('MyModel', Schema);


// Controller.js
var mongoose = require('mongoose');
var MyModel = mongoose.model('MyModel'); // Retrieves the model ok

MyModel.find({}, function(err, docs){
   if(err){} //
   console.log(docs); // Does not work
});

However this doesn’t work… it only works if somehow I pass the connection across like so:

// Datastore.js
var mongoose = require('mongoose'),
    conn = mongoose.createConnection();

...

conn.open(host, database, port, options, callback); //

mongoose.set('db', conn);


// Controller.js
var mongoose = require('mongoose'),
    db = mongoose.get('db');

var MyModel = db.model('MyModel'); // Retrieve the model using the connection instance

MyModel.find({}, function(err, docs){
   if(err){} //
   console.log(docs); // Works
});

I think I’m approaching this in the wrong way… should the first approach work, and I’m doing something wrong?

Answer 1

It’s easiest to just open the default connection pool that’s shared by all your mongoose calls:

// Datastore.js
var mongoose = require('mongoose'),
    db = mongoose.connect('localhost', 'dbname');

Then in all your other files access the pool using mongoose.model(...).