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Failed to load c++ bson extension

A total node noob here. I've been trying to set up a sample node app but the following error keeps popping up every time I try to run:

node app

Failed to load c++ bson extension, using pure JS version

events.js:72
        throw er; // Unhandled 'error' event
              ^
Error: failed to connect to [#$%67890 :27017]
    at null.<anonymous> (/home/thejazeto/code/nodejs/authen/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/server.js:553:74)
    at EventEmitter.emit (events.js:106:17)
    at null.<anonymous> (/home/thejazeto/code/nodejs/authen/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/connection_pool.js:140:15)
    at EventEmitter.emit (events.js:98:17)
    at Socket.<anonymous> (/home/thejazeto/code/nodejs/authen/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/connection.js:512:10)
    at Socket.EventEmitter.emit (events.js:95:17)
    at net.js:830:16
    at process._tickCallback (node.js:415:13)

How do I limit the number of returned items?

myModel.find({}, function(err, items){
console.log(items.length);    // big number
});

How can I limit the returned items to only the latest 10 items that were inserted?

passport.js passport.initialize() middleware not in use

I am using node with express + mongoose and trying to use passport.js with restful api.
I keep getting this exception after authentication success (I see the callback url on the browser):

/Users/naorye/dev/naorye/myproj/node_modules/mongoose/lib/utils.js:419
        throw err;
              ^
Error: passport.initialize() middleware not in use
    at IncomingMessage.req.login.req.logIn (/Users/naorye/dev/naorye/myproj/node_modules/passport/lib/passport/http/request.js:30:30)
    at Context.module.exports.delegate.success (/Users/naorye/dev/naorye/myproj/node_modules/passport/lib/passport/middleware/authenticate.js:194:13)
    at Context.actions.success (/Users/naorye/dev/naorye/myproj/node_modules/passport/lib/passport/context/http/actions.js:21:25)
    at verified (/Users/naorye/dev/naorye/myproj/node_modules/passport-facebook/node_modules/passport-oauth/lib/passport-oauth/strategies/oauth2.js:133:18)
    at Promise.module.exports.passport.use.GitHubStrategy.clientID (/Users/naorye/dev/naorye/myproj/config/passport.js:91:24)
    at Promise.onResolve (/Users/naorye/dev/naorye/myproj/node_modules/mongoose/node_modules/mpromise/lib/promise.js:162:8)
    at Promise.EventEmitter.emit (events.js:96:17)
    at Promise.emit (/Users/naorye/dev/naorye/myproj/node_modules/mongoose/node_modules/mpromise/lib/promise.js:79:38)
    at Promise.fulfill (/Users/naorye/dev/naorye/myproj/node_modules/mongoose/node_modules/mpromise/lib/promise.js:92:20)
    at /Users/naorye/dev/naorye/myproj/node_modules/mongoose/lib/query.js:1822:13

I have read that I should put app.use(passport.initialize()); and app.use(passport.session()); before app.use(app.router); and this is what I did. Here is my express.js that registers the middlewares:

var express = require('express'),
    mongoStore = require('connect-mongo')(express),
    flash = require('connect-flash'),
    helpers = require('view-helpers');

module.exports = function (app, config, passport) {
    app.set('showStackError', true);
    // should be placed before express.static
    app.use(express.compress({
        filter: function (req, res) {
            return /json|text|javascript|css/.test(res.getHeader('Content-Type'));
        },
        level: 9
    }));
    app.use(express.favicon());
    app.use(express.static(config.root + '/public'));

    app.use(express.logger('dev'));

    // set views path, template engine and default layout
    app.set('views', config.root + '/app/views');
    app.set('view engine', 'jade');

    app.configure(function () {
        // use passport session
        app.use(passport.initialize());
        app.use(passport.session());

        // dynamic helpers
        app.use(helpers(config.app.name));

        // cookieParser should be above session
        app.use(express.cookieParser());

        // bodyParser should be above methodOverride
        app.use(express.bodyParser());
        app.use(express.methodOverride());

        // express/mongo session storage
        app.use(express.session({
            secret: 'linkit',
            store: new mongoStore({
                url: config.db,
                collection : 'sessions'
            })
        }));

        // connect flash for flash messages
        app.use(flash());

        // routes should be at the last
        app.use(app.router);

        // assume "not found" in the error msgs
        // is a 404. this is somewhat silly, but
        // valid, you can do whatever you like, set
        // properties, use instanceof etc.
        app.use(function(err, req, res, next){
            // treat as 404
            if (~err.message.indexOf('not found')) {
                return next();
            }

            // log it
            console.error(err.stack);

            // error page
            res.status(500).render('500', { error: err.stack });
        });

        // assume 404 since no middleware responded
        app.use(function(req, res, next){
            res.status(404).render('404', {
                url: req.originalUrl,
                error: 'Not found'
            });
        });
    });
};

What is wrong?

UPDATE According to @Peter Lyons I have changed the configurations order to the following, but I still got the same error:

var express = require('express'),
    mongoStore = require('connect-mongo')(express),
    flash = require('connect-flash'),
    helpers = require('view-helpers');

module.exports = function (app, config, passport) {
    app.set('showStackError', true);
    // should be placed before express.static
    app.use(express.compress({
        filter: function (req, res) {
            return /json|text|javascript|css/.test(res.getHeader('Content-Type'));
        },
        level: 9
    }));
    app.use(express.favicon());
    app.use(express.static(config.root + '/public'));

    app.use(express.logger('dev'));

    // set views path, template engine and default layout
    app.set('views', config.root + '/app/views');
    app.set('view engine', 'jade');

    app.configure(function () {

        // dynamic helpers
        app.use(helpers(config.app.name));

        // cookieParser should be above session
        app.use(express.cookieParser());

        // bodyParser should be above methodOverride
        app.use(express.bodyParser());
        app.use(express.methodOverride());

        // express/mongo session storage
        app.use(express.session({
            secret: 'linkit',
            store: new mongoStore({
                url: config.db,
                collection : 'sessions'
            })
        }));

        // connect flash for flash messages
        app.use(flash());

        // use passport session
        app.use(passport.initialize());
        app.use(passport.session());

        // routes should be at the last
        app.use(app.router);

        // assume "not found" in the error msgs
        // is a 404. this is somewhat silly, but
        // valid, you can do whatever you like, set
        // properties, use instanceof etc.
        app.use(function(err, req, res, next){
            // treat as 404
            if (~err.message.indexOf('not found')) {
                return next();
            }

            // log it
            console.error(err.stack);

            // error page
            res.status(500).render('500', { error: err.stack });
        });

        // assume 404 since no middleware responded
        app.use(function(req, res, next){
            res.status(404).render('404', {
                url: req.originalUrl,
                error: 'Not found'
            });
        });
    });
};

MongoDB/Mongoose querying at a specific date?

Is it possible to query for a specific date ?

I found in the mongo Cookbook that we can do it for a range Querying for a Date Range Like that :

db.posts.find({"created_on": {"$gte": start, "$lt": end}})

But is it possible for a specific date ? This doesn't work :

db.posts.find({"created_on": new Date(2012, 7, 14) })

How can I generate an ObjectId with mongoose?

I'd like to generate a MongoDB ObjectId with Mongoose. Is there a way to access the ObjectId constructor from Mongoose?

mongoose vs mongodb (nodejs modules/extensions), which better? and why?

Im just arrive to nodejs and se that there are many libs to use with mongodb, the most popular seems to be these two (mongoose and mongodb) can I get pros and cons of those extensions? There are better or alternatives to this two?

Edit: Found a new library that seems also interesting node-mongolian and is "Mongolian DeadBeef is an awesome Mongo DB node.js driver that attempts to closely approximate the mongodb shell." (readme.md)

https://github.com/marcello3d/node-mongolian

This is just to add more resources to new people that view this, so basically Mongolian its like an ODM...

What does `!!~` mean in javascript? [duplicate]

Possible Duplicate:
What does tilde (~) preceding jQuery object do?

I found a strange !!~ in the code when reading: https://github.com/LearnBoost/mongoose/blob/master/lib/document.js#L678

Document.prototype.isModified = function (path) {
  return !!~this.modifiedPaths.indexOf(path);
};

I have read that What is the !! (not not) operator in JavaScript? and How to: The ~ operator?; why did the author use !!~ here?

I tried:

!!~1  // -> true
!!~0  // -> true
!!~-1 // -> false
!!~-2 // -> true

It seems that it only be false when the number is -1. Is it right? Why not just check the number is not -1 or >=0?

Mongoose -- Force collection name

I am trying to use mongoose to create a databse and a collection in it.My code is:

var mongoose = require('mongoose');
    var db = mongoose.connect('mongodb://localhost/testdb');
    var Schema = mongoose.Schema;

    var UserInfo = new Schema({
    username : String,
    password : String 
    });

    mongoose.model('UserInfo', UserInfo);

    var user = db.model('UserInfo');


    var admin = new user();
    admin.username = "sss";
    admin.password = "ee";
    admin.save();

When i run this code, mongoose creted collection named UserInfos instead of userinfo. Can someone help me how to force collection name in mongoose?

How to do authentication with Node.js, Express and Mongoose?

I've made simple nodejs application by using nodejs+express. Now I want to make user authentification. I want to realize session handling by using mongoose. Can you advise some example?

In Mongoose, how do I sort by date? (node.js)

let's say I run this query in Mongoose:

Room.find({}, function(err,docs){

}).sort({date:-1}); 

This doesn't work!

drop database with mongoose

I'm preparing a db creation script in node.js + mongoose. How can I check if the database already exists, and if so drop (delete) it using mongoose? I Could not find a way to drop with mongoose.

add created_at and updated_at fields to mongoose schemas

Is there a way to add created_at and updated_at fields to a mongoose schema, without having to pass them in everytime new MyModel() is called?

The created_at field would be a date and only added when a document is created. The updated_at field would be updated with new date whenever save() is called on a document.

I have tried this in my schema, but the field does not show up unless I expcitly add it:

var ItemSchema = new Schema({
    name    : { type: String, required: true, trim: true }
  , created_at    : { type: Date, required: true, default: Date.now }
});

Comparing mongoose _id and strings

I have a node.js application that pulls some data and sticks it into an object, like this:

var results = new Object();

User.findOne(query, function(err, u) {
    results.userId = u._id;
}

When I do an if/then based on that stored ID, the comparison is never true:

if (results.userId == AnotherMongoDocument._id) {
    console.log('This is never true');
}

When I do a console.log of the two id's, they match exactly:

User id: 4fc67871349bb7bf6a000002 AnotherMongoDocument id: 4fc67871349bb7bf6a000002

I am assuming this is some kind of datatype problem, but I'm not sure how to convert results.userId to a datatype that will result in the above comparison being true and my outsourced brain (aka Google) has been unable to help.

How to access a preexisting collection with Mongoose?

So I have a large collection of 300 question objects in a database test. I can interact with this collection easily through MongoDB's interactive shell; however, when I try to get the collection through Mongoose in an express.js application I get an empty array.

My question is, how can I access this already existant dataset instead of recreating it in express? Here's some code:

var mongoose = require('mongoose');
var Schema = mongoose.Schema;

mongoose.connect('mongodb://localhost/test');
mongoose.model('question', new Schema({ url: String, text: String, id: Number }));

var questions = mongoose.model('question');
questions.find({}, function(err, data) { console.log(err, data, data.length); });

This outputs:

null [] 0

Mongoose indexing in production code

Per the Mongoose documentation for MongooseJS and MongoDB/Node.js :

When your application starts up, Mongoose automatically calls ensureIndex for each defined index in your schema. While nice for development, it is recommended this behavior be disabled in production since index creation can cause a significant performance impact. Disable the behavior by setting the autoIndex option of your schema to false.

This appears to instruct removal of auto-indexing from mongoose prior to deploying to optimize Mongoose from instructing Mongo to go and churn through all indexes on application startup, which seems to make sense.

What is the proper way to handle indexing in production code? Maybe an external script should generate indexes? Or maybe ensureIndex is unnecessary if a single application is the sole reader/writer to a collection because it will continue an index every time a DB write occurs?

Edit: To supplement, MongoDB provides good documentation for the how to do indexing, but not why or when explicit indexing directives should be done. It seems to me that indexes should be kept up to date by writer applications automatically on collections with existing indexes and that ensureIndex is really more of a one-time thing (done when a new index is being applied), in which case Mongoose's autoIndex should be a no-op under a normal server restart.