arel-mongo¶ ↑

An experimental MongoDB engine for Arel.

A Quick Tour¶ ↑

Arel::Collection is comparable to Arel::Table. Collections may be initialized with attributes for typecasting:

users = Collection.new(:users,
  :attributes => [[:name, Attributes::String, :profile, Attributes::Hash]])

users.insert([{ :name => 'bob', :profile => { :location => 'Earth', :rating => 1 } }])

The standard Arel predicates and operators work as expected.

users.where(users[:name].eq('bob'))
# => { users[:_id] => ..., users[:name] => 'bob', users[:profile] => {...} }

But this would all be pointless without support for embedded documents,

users.where(users['profile.location'].eq('Earth'))
users.where(users[:profile].elem(users['profile.rating'].gte(1), users['profile.location'].eq('Earth')))

and Mongo-specific predicates:

users.where(users[:name].exists(true))

Arel Mongo also supports MongoDB cursors with efficient caching thanks to Hamster.

What about atomic updates?

users.where(users[:name].eq('bob')).update(users['profile.rating'].incr(1))

Sweet!

Status¶ ↑

This is a conversation-starter for now.

Note on Patches/Pull Requests¶ ↑

• Fork the project.

• Make your feature addition or bug fix.

• Add tests for it. This is important so I don’t break it in a future version unintentionally.

• Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)

• Send me a pull request. Bonus points for topic branches.

Copyright¶ ↑

Copyright © 2010 akdubya. See LICENSE for details.