ActiveMongoid

ActiveMongoid facilitates usage of both ActiveRecord and Mongoid in a single rails application by providing an ActiveRecord-like interface for inter-ORM relations. It was written to replace select Mongoid models with ActiveRecord versions so it tries to adhere to the Mongoid API as closely as possible. To accomplish this compatibility, much of the logic and structure of this lib are either directly inspired by or straight up ripped off the Mongoid source.

Add this line to your application's Gemfile:

gem 'active_mongoid'

And then execute:

$ bundle

Or install it yourself as:

$ gem install active_mongoid

To add ActiveMongoid associations, simply add the ActiveMongoid::Associations module in both models and define the relations using the provided macros as you would with either ActiveRecord or Mongoid.

class Player < ActiveRecord::Base
  include ActiveMongoid::Associations

  belongs_to_document :team
  has_one_document :stat, as: :target, autosave: true, dependent: :destroy
end

class Team
  include Mongoid::Document
  include ActiveMongoid::Associations

  has_many_records :players, autosave: true, order: "name asc"
  belongs_to_record :division
end

Then you can interact with the models and relations just as you would with either ActiveRecord or Mongoid.

> team = Team.create
=> #<Team _id: 5453d55cb736b692ab000001, name: nil>
> player = team.players.build(name: "foo") # create will call save
=> #<Player id: nil, name: "foo", team_id: "5453d55cb736b692ab000001">
> team.player << Player.new(name: "foo1")
=> #<Player id: nil, name: "foo1", team_id: "5453d55cb736b692ab000001">
> team.players
=> [#<Player id: nil, name: "foo", team_id: "5453d55cb736b692ab000001">, #<Player id: nil, name: "foo1", team_id: "5453d55cb736b692ab000001">] 
> player.team # binds the inverse
=> #<Team _id: 5453d55cb736b692ab000001, name: nil>
> team.save
=> true
> team.players
=> [#<Player id: 1, name: "foo", team_id: "5453d55cb736b692ab000001">, #<Player id: 2, name: "foo1", team_id: "5453d55cb736b692ab000001">] 
> team.players.where(name: "foo") # returns relation so chaining is possible
=> [#<Player id: 1, name: "foo", team_id: "5453d55cb736b692ab000001">]
> team.players.where(name: "foo").where(id: 1)
=> [#<Player id: 1, name: "foo", team_id: "5453d55cb736b692ab000001">]  
> player = Player.create(name: "baz")
=> #<Player id: 3, name: "baz", team_id: nil>
> team = player.build_team(name: "bar")  # create_ will call save
=> #<Team _id: 5453d55cb736b692ab000002, name: "bar">
> team.players
=> [#<Player id: 3, name: "foo", team_id: "5453d55cb736b692ab000002">] 
> player.team(true) # forces reload from database
=> nil 

• has_many_records :players
• has_many_documents :stats

Options:

• order Needs to be formated according to ActiveRecord/Mongoid spec respectively
• dependent Accepts: :destroy, :delete
• as Polymorphic relation
• foreign_key Foreign key for relation
• primary_key Primary key for relation
• class_name Association class name
• autosave Accepts :true

• has_one_record :player
• belongs_to_record :player
• has_one_record :stat
• belongs_to_record :stat

Options:

• dependent Accepts: :destroy, :delete
• as Polymorphic relation
• foreign_key Foreign key for relation
• primary_key Primary key for relation
• class_name Association class name
• autosave Accepts :true

• team.players Returns the relation
• team.players(true) Forces reload from database and returns relation
• team.players = [player] Assigns objects and calls dependent method on old values
• team.players << player Appends object and will save if base is persisted
• team.players.build({player.attributes}) Builds and binds object from attributes and binds relation
• team.players.concat([player_1, player_2] Appends and binds array of objects. Will save if base is persisted
• team.players.purge Removes all objects from relation and calls dependent method on objects
• team.players.delete(player) Removes object and calls dependent method on object
• team.players.delete_all(optional_criteria) Calls delete on all objects
• team.players.destroy_all(optional_criteria) Calls destroy on all objects
• team.players.each Iterates on on objects
• team.players.exists? Calls exists? on relation
• team.players.find(params) Returns relation with criteria added
• team.players.nullify Clears loaded relation
• team.players.blank? Returns true if empty
• team.players.create({player.attributes}) Creates and binds from attributes
• team.players.create!({player.attributes}) Creates and binds form attributes and raises an exception if fails
• team.players.find_or_create_by({player.attributes}) Finds or creates a record from attributes
• team.players.find_or_initialize_by({player.attributes}) Finds or initializes a record from attributes
• team.players.nil? returns false

All other methods will defer to the ActiveRecord/Mongoid relation respectively.

• player.stat Returns the relation
• player.stat(true) Forces reload from database and returns relation
• player.stat = stat Assigns object as relation. Will substitute old value and call dependent method
• player.build_stat({}) Builds and binds new object from attributes
• player.create_stat({}) Creates and binds new object from attributes

All other methods called on relation will defer to the object.

The BsonId module faciliates the useage of BSON::ObjectId's on ActiveRecord objects. This module is especially helpful if you are migrating a model from a Mongoid object to an ActiveRecord object and want to carry over the old id.

class Division < ActiveRecord::Base
  include ActiveMongoid::BsonId
  bsonify_attr :_id, initialize: true
end

> division._id
=> BSON::ObjectId('545289a7b736b6586a000001')
> division._id = BSON::ObjectId('545289a7b736b6586a000002')
=> BSON::ObjectId('545289a7b736b6586a000002')
> division._id = '545289a7b736b6586a000002'
=> BSON::ObjectId('545289a7b736b6586a000002')

class Play < ActiveRecord::Base
  include ActiveMongoid::Associations
  include ActiveMongoid::Finders
  include ActiveMongoid::BsonId

  bsonify_attr :id, initialize: true, primary: true
end

> play.id
=> '545289a7b736b6586a000001' # An issue with ActiveRecord does not allow casting this particular accessor
> play.id = BSON::ObjectId('545289a7b736b6586a000002')
=> BSON::ObjectId('545289a7b736b6586a000002')
> play._id = '545289a7b736b6586a000002'
=> BSON::ObjectId('545289a7b736b6586a000002')

This module proxies the existing ActiveRecord find and where to perform casting of BSON::ObjectId's to string for queries. Additionally it'll default to the _id field if the object is a valid BSON::ObjectId and the _id field is present on the model.

class Division < ActiveRecord::Base
  include ActiveMongoid::BsonId
  include ActiveMongoid::Finders
  bsonify_attr :_id, initialize: true
end

> Division.find(1)
=> #<Division id: 1, _id: "545289a7b736b6586a000001", name: "new">
> Division.find(BSON::ObjectId('545289a7b736b6586a000001')
=> #<Division id: 1, _id: "545289a7b736b6586a000001", name: "new">
> Division.where(_id: BSON::ObjectId('545289a7b736b6586a000001')
=> [#<Division id: 1, _id: "545289a7b736b6586a000001", name: "new">]
> Division.where(id: BSON::ObjectId('545289a7b736b6586a000001')
=> [#<Division id: 1, _id: "545289a7b736b6586a000001", name: "new">]

1. Fork it ( https://github.com/[my-github-username]/active_mongoid/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request