Circle

gem 'circle'

$ bundle

$ gem install circle

$ rails g circle:migration

class User < ActiveRecord::Base
  has_circle
end

john = User.find_by_login 'john'
mary = User.find_by_login 'mary'
paul = User.find_by_login 'paul'

# John wants to be friends with Mary
# always return a friendship object
john.befriend(mary)

# Are they friends?
john.friends?(mary) ==> false

# Get the friendship object
john.friendship_with(mary)

# Mary accepts John's request if it exists
mary.accept_friend_request(john)
mary.friends?(john) ==> true

# If both users request a friendship through befriend, they become friends.
john.befriend(mary)
mary.befriend(john)
mary.friends?(john) ==> true

# Mary can reject John's friendship.
mary.deny_friend_request(john)

# If you're dealing with a friendship object,
# the following methods are available
friendship.accept! # accept the request
friendship.deny! # deny the request
friendship.block!(true/false) # block request and add to the users block list if passed true. This is so you can have a one sided block (e.g. The user that initiated the block has the user put in their block list and the blocked user doesn't have the initiating user put in theirs)

# The befriend method returns the friendship object and status.
# The friendship object will be present only when the friendship is created
# (that is, when is requested for the first time)
# STATUS_ALREADY_FRIENDS       # => Users are already friends
# STATUS_ALREADY_REQUESTED     # => User has already requested friendship
# STATUS_IS_YOU                # => User is trying add himself as friend
# STATUS_FRIEND_IS_REQUIRED    # => Friend argument is missing
# STATUS_FRIENDSHIP_ACCEPTED   # => Friendship has been accepted
# STATUS_REQUESTED             # => Friendship has been requested
# STATUS_CANNOT_SEND           # => User cannot send friend requests
# STATUS_BLOCKED               # => User has been blocked

friendship, status = mary.befriend(john)

if status == Circle::Friendship::STATUS_REQUESTED
  # the friendship has been requested
  Mailer.deliver_friendship_request(friendship)
elsif status == Circle::Friendship::STATUS_ALREADY_FRIENDS
  # they're already friends
else
  # ...
end

# You can specify whether or not a user can send or accept friend requests by defining two methods that return true or false.
# If these are not defined, it is assumed true.

class User < ActiveRecord::Base
  has_circle

  def can_send_friend_request?
    # check subscription plan or whatever
  end

  def can_accept_friend_request?
    # check subscription plan or whatever
  end
end