Friendable

You don't want to implement friendship functionality with RDB any more? But you think it's still too early to use graphDB? Use Redis!

Installation

Add this line to your application's Gemfile:

gem 'friendable'

And then execute:

$ bundle

Next, include Friendable::UserMethods inside User class or something like that you use in your application:

class User < ActiveRecord::Base
  include Friendable::UserMethods

  ...
end

Create a config file like below to set up Redis connection and save it as config/initializers/friendable.rb:

Friendable.redis = Redis.new(host: "localhost", port: 6379)

Usage

Being a friend

user         = User.first
another_user = User.last

user.friends                # => empty ActiveRecord::Relation
user.friend?(another_user)  # => false

 # they are now friends!
current_user.friend!(another_user)

user.friend?(another_user)           # => true
user.friends.include?(another_user)  # => true
another_user.friend?(user)           # => true
another_user.friends.include?(user)  # => true

You can also pass properties about their relationship. For example, if you want to store where they meet, you can do something like this:

friendship = user.friend!(another_user, :meeting_place => "Red Rock")

friendship.meeting_place  # => "Red Rock"
friendship.created_at     # => "2012-09-23 14:24:03"
friendship.updated_at     # => "2012-09-23 14:24:03"

If you want to find the specific friendship with somebody and edit/save the friendship, you can do it by using #write_attribute and #save:

friendship = user.friendship_with(another_user)
friendship.write_attribute(:close_friend, true)
friendship.save

friendship.close_friend   # => true
friendship.meeting_place  # => "Red Rock"
friendship.created_at     # => "2012-09-23 14:24:03"
friendship.updated_at     # => "2012-09-23 14:25:21"

Note: properties are not saved on the opposite direction of the friendship.

user.friend!(another_user, :meeting_place => "Red Rock")

friendship = user.friendship_with(another_user)
friendship.meeting_place  # => "Red Rock"

friendship = another_user.friendship_with(user)  # opposite
friendship.meeting_place  # => NoMethodError

Removing a friend

You can remove a user from the friend list of a user like this:

user.unfriend!(another_user)

user.friend?(another_user)                 # => false
user.friends.include?(another_user)        # => false
user.friend_ids.include?(another_user.id)  # => false

For more details, have a look at the documentation.

Support

Ruby version: 1.9.3, 1.9.2, 1.8.7 and REE
ORM: ActiveRecord

You also(and of course) need to install Redis.

Contributing

Fork it
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request