initial design for the subscription model

Rakefile

@@ -7,6 +7,8 @@ require 'active_support/all'
 require 'sinatra'
 require 'mongoid/tree'
 require 'voteable_mongo'
+require './lib/watchable'
+require './lib/followable'
 
 desc "Load the environment"
 task :environment do
@@ -19,10 +21,10 @@ end
 namespace :db do
   task :seed => :environment do
 
-    require_relative 'models/comment.rb'
-    require_relative 'models/comment_thread.rb'
-    require_relative 'models/user.rb'
-    require_relative 'models/commentable.rb'
+    require './models/comment.rb'
+    require './models/comment_thread.rb'
+    require './models/user.rb'
+    require './models/commentable.rb'
 
     Commentable.delete_all
     Comment.delete_all

app.rb

@@ -7,11 +7,13 @@ require 'active_support/all'
 require 'sinatra'
 require 'mongoid/tree'
 require 'voteable_mongo'
+require './lib/followable'
+require './lib/watchable'
 
-require_relative 'models/comment'
-require_relative 'models/comment_thread'
-require_relative 'models/commentable'
-require_relative 'models/user'
+require './models/comment'
+require './models/comment_thread'
+require './models/commentable'
+require './models/user'
 
 env_index = ARGV.index("-e")
 env_arg = ARGV[env_index + 1] if env_index
@@ -47,8 +49,6 @@ config = YAML.load_file("config/application.yml")
 # POST /api/v1/users/:user_id/feeds/subscribe
 #
 
-
-
 # DELETE /api/v1/commentables/:commentable_type/:commentable_id
 # delete the commentable object and all of its associated comment threads and comments
 

lib/followable.rb

+require_relative 'followable/followable'

lib/followable/followable.rb

+module Mongoid
+  module Followable
+    extend ActiveSupport::Concern
+
+    included do
+      has_and_belongs_to_many :followers, class_name: self.name, inverse_of: :followings
+      has_and_belongs_to_many :followings, class_name: self.name, inverse_of: :followers, autosave: true
+    end
+
+    def follow(user)
+      if self.id != user.id and not self.following.include? user
+        self.following << user
+      end
+    end
+
+    def unfollow(user)
+      self.following.delete(user)
+    end
+  end
+end

lib/watchable.rb

+require_relative 'watchable/watchable'
+require_relative 'watchable/watcher'

lib/watchable/watchable.rb

+module Mongoid
+  module Watchable
+    extend ActiveSupport::Concern
+    included do
+      has_and_belongs_to_many :watchers, class_name: "User", inverse_of: "watched_#{self.name.underscore.pluralize}".intern
+    end
+  end
+end

lib/watchable/watcher.rb

+module Mongoid
+  module Watcher
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      def watching(class_plural_sym)
+        class_plural = class_plural_sym.to_s
+        class_single = class_plural.singularize
+        class_name = class_single.camelize
+        watched_symbol = "watched_#{class_plural}".intern
+
+        has_and_belongs_to_many watched_symbol, class_name: class_name, inverse_of: :watchers, autosave: true
+
+        self.class_eval <<-END
+          def watch_#{class_single}(watching_object)
+            if not self.watched_#{class_plural}.include? watching_object
+              self.watched_#{class_plural} << watching_object
+            end
+          end
+
+          def unwatch_#{class_single}(watching_object)
+            self.watched_#{class_plural}.delete(watching_object)
+          end
+        END
+      end
+    end
+  end
+end

models/comment_thread.rb

@@ -2,6 +2,7 @@ class CommentThread
   include Mongoid::Document
   include Mongo::Voteable
   include Mongoid::Timestamps
+  include Mongoid::Watchable
 
   voteable self, :up => +1, :down => -1
 
@@ -9,7 +10,7 @@ class CommentThread
   field :body, type: String
   field :course_id, type: String, index: true
 
-  belongs_to :author, class_name: "User", index: true
+  belongs_to :author, class_name: "User", inverse_of: :comment_threads, index: true
   belongs_to :commentable, index: true
   has_many :comments, dependent: :destroy # Use destroy to envoke callback on the top-level comments
 

models/commentable.rb

 class Commentable
   include Mongoid::Document
-  
+  include Mongoid::Watchable 
+
   field :commentable_type, type: String
   field :commentable_id, type: String
 

models/user.rb

 class User
   include Mongoid::Document
   include Mongo::Voter
+  include Mongoid::Watcher
+  include Mongoid::Followable
 
   field :external_id, type: String
+  
+  watching :comment_threads
+  watching :commentables
 
   has_many :comments
-  has_many :commentable
+  has_many :comment_threads, inverse_of: :author
 
   attr_accessible :external_id