Model schemas and relationships for "follower" and "followed" users

event.rb

# == Schema Information
#
# Table name: events
#
#  id         :integer          not null, primary key
#  title      :string(255)
#  user_id    :integer
#  created_at :datetime         not null
#  updated_at :datetime         not null
#

class Event < ActiveRecord::Base
  belongs_to :user
end

follow_up_relationship.rb

# == Schema Information
#
# Table name: follow_up_relationships
#
#  id          :integer          not null, primary key
#  follower_id :integer
#  user_id     :integer
#  created_at  :datetime         not null
#  updated_at  :datetime         not null
#

class FollowUpRelationship < ActiveRecord::Base
  belongs_to :user
  belongs_to :follower, :class_name => "User"
end

user.rb

# == Schema Information
#
# Table name: users
#
#  id                     :integer          not null, primary key
#  name                   :string(255)      not null
#  created_at             :datetime         not null
#  updated_at             :datetime         not null
#

class User < ActiveRecord::Base
  attr_accessible :name

  validates_presence_of :name

  has_many :follower_relationships, :class_name => "FollowUpRelationship"
  has_many :followers, :through => :follower_relationships

  has_many :followed_relationships, :class_name => "FollowUpRelationship", :foreign_key => :follower_id
  has_many :followeds, :through => :followed_relationships, :source => :user

  has_many :events

  def followed_events
    Event.where(:user_id => followeds)
  end
end