installation

prerequisites

There are a few things you need to have in your toolbox before tackling a web application using Mongoid.

• A good to advanced knowledge of Ruby.
• Have good knowledge of your web framework if using one.
• A thorough understanding of MongoDB.

This may seem like a "thank you Captain Obvious" moment, however if you believe that you can just hop over to Mongoid because you read a blog post on how cool Ruby and MongoDB were, you are in for a world of pain.

Mongoid leverages many aspects of the Ruby programming language that are not for beginner use, and sending the core team into a frenzy tracking down a bug for a common Ruby mistake is a waste of our time, and all of the other users of the framework as well.

THE DATABASE IS NOT A BLACK BOX.

Mongoid is an abstraction to make application developers' lives easier, however the internals leverage the power of MongoDB and it is truly important to know what is going on under the covers. This is why the documentation provides the exact queries that Mongoid is executing against the database when you call a persistence operation. If we took the time to tell you, you should listen. :)

okay, now i'm ready

The preferred method for installing Mongoid is with bundler. Add the Mongoid and optional BSON extenstions to your Gemfile:

gem "mongoid", "~> 2.4"
gem "bson_ext", "~> 1.5"

Alternatively you can get the Mongoid gem direcly from rubygems.org:

$ gem install mongoid bson_ext

Note for performance improvements you will want to also install the bson c extensions if compatible with your system, however it is not a direct dependency of Mongoid in case it is not compatible.