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POPassing reference to DB into routes is not working for my Node / Express project
 

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    <p>I am using node + express to create a simple REST API, and am trying to separate out routing logic from db logic. I am having a problem getting access to the DB from the routes.</p> <p>Here is my server.js code:</p> <pre><code>var express = require('express') , path = require('path') , http = require('http') , mongo = require('mongodb'); // Configure Express app var app = express(); app.configure(function () { app.set('port', process.env.PORT || 3000); app.use(express.logger('dev')); /* 'default', 'short', 'tiny', 'dev' */ app.use(express.bodyParser()), app.use(express.static(path.join(__dirname, 'public'))); }); // Configure DB var Server = mongo.Server , Db = mongo.Db , BSON = mongo.BSONPure , server = new Server('localhost', 27017, {auto_reconnect: true}) , db = new Db('mydb', server, {safe: true}); // Open DB to see if we need to populate with data db.open(function(err, db) { if(!err) { console.log("Connected to 'mydb' database"); var Post = require('./routes/posts') , post = new Post(db); // Set the routes app.get('/:org/posts', post.find); app.get('/:org/posts/:id', post.get); app.post('/:org/posts', post.add); app.put('/:org/posts/:id', post.update); app.delete('/:org/posts/:id', post.remove); // Fire up the server http.createServer(app).listen(app.get('port'), function () { console.log("Express server listening on port " + app.get('port')); }); } }); </code></pre> <p>and here is the logic in the post.js file:</p> <pre><code>var Post = function(db) { this.db = db; }; Post.prototype.get = function(req, res) { var id = req.params.id; var org = req.params.org; var db = this.db; console.log('Retrieving post: ' + id + ' from org: ' + org); db.collection('ads', function(err, collection) { collection.findOne({'_id':new BSON.ObjectID(id), 'org':org}, function(err, item) { res.send(item); }); }); }; Post.prototype.find = function(req, res) { var org = req.params.org; var db = this.db; console.log('Finding posts for org: ' + org); db.collection('posts', function(err, collection) { collection.find({'org':org}).toArray(function(err, items) { res.send(items); }); }); }; Post.prototype.add = function(req, res) { var org = req.params.org; var post = req.body; var db = this.db; console.log('Adding post: ' + JSON.stringify(post) + ' for org: ' + org); db.collection('posts', function(err, collection) { collection.insert(post, {safe:true}, function(err, result) { if (err) { res.send({'error':'An error has occurred'}); } else { console.log('Success: ' + JSON.stringify(result[0])); res.send(result[0]); } }); }); }; Post.prototype.update = function(req, res) { var id = req.params.id; var org = req.params.org; var post = req.body; var db = this.db; delete post._id; console.log('Updating post: ' + id + ', org: ' + org); console.log(JSON.stringify(post)); db.collection('posts', function(err, collection) { collection.update({'_id':new BSON.ObjectID(id)}, post, {safe:true}, function(err, result) { if (err) { console.log('Error updating post: ' + err); res.send({'error':'An error has occurred'}); } else { console.log('' + result + ' document(s) updated'); res.send(post); } }); }); }; Post.prototype.remove = function(req, res) { var id = req.params.id; var org = req.params.org; var db = this.db; console.log('Deleting post: ' + id + ', org: ' + org); db.collection('posts', function(err, collection) { collection.remove({'_id':new BSON.ObjectID(id), 'org':org}, {safe:true}, function(err, result) { if (err) { res.send({'error':'An error has occurred - ' + err}); } else { console.log('' + result + ' document(s) deleted'); res.send(req.body); } }); }); }; module.exports = Post; </code></pre> <p>I would think that the post object would hold on to the db reference for use when it is called from the routes, but I get the following error:</p> <pre><code>TypeError: Cannot call method 'collection' of undefined at Post.find (../routes/posts.js:23:6) </code></pre> <p>Can anyone point me in the right direction? Many thanks</p>
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