User following

app/controllers/relationships_controller.rb

@@ -0,0 +1,21 @@
+class RelationshipsController < ApplicationController
+  before_action :signed_in_user
+
+  def create
+    @user = User.find(params[:relationship][:followed_id])
+    current_user.follow!(@user)
+    respond_to do |format| # only one of these lines gets executed based on the type of request (HTTP vs Ajax)
+      format.html { redirect_to @user }
+      format.js
+    end
+  end
+
+  def destroy
+    @user = Relationship.find(params[:id]).followed
+    current_user.unfollow!(@user)
+    respond_to do |format|
+      format.html { redirect_to @user }
+      format.js
+    end
+  end
+end

app/controllers/users_controller.rb

@@ -1,6 +1,6 @@
 class UsersController < ApplicationController
   before_action :not_new_user, only: [:new, :create]
-  before_action :signed_in_user, only: [:index, :edit, :update, :destroy]
+  before_action :signed_in_user, only: [:index, :edit, :update, :destroy, :following, :followers]
   before_action :correct_user, only: [:edit, :update]
   before_action :admin_user, only: :destroy
 
@@ -46,6 +46,20 @@ def destroy
     redirect_to users_url
   end
 
+  def following
+    @title = "Following"
+    @user = User.find(params[:id])
+    @users = @user.followed_users
+    render 'show_follow'
+  end
+
+  def followers
+    @title = "Followers"
+    @user = User.find(params[:id])
+    @users = @user.followers
+    render 'show_follow'
+  end
+
   private
 
     def user_params

app/models/post.rb

@@ -4,4 +4,12 @@ class Post < ActiveRecord::Base
   validates :user_id, presence: true
   validates :content, presence: true
   validates :title, presence: true, length: { maximum: 150 }
+
+  def self.from_users_followed_by(user)
+    followed_user_ids = "SELECT followed_id FROM relationships
+                         WHERE follower_id = :user_id"
+
+    where("user_id IN (#{followed_user_ids}) OR user_id = :user_id",
+          user_id: user.id)
+  end
 end

app/models/relationship.rb

@@ -0,0 +1,7 @@
+class Relationship < ActiveRecord::Base
+  belongs_to :follower, class_name: "User"
+  belongs_to :followed, class_name: "User"
+
+  validates :follower_id, presence: true
+  validates :followed_id, presence: true
+end

app/models/user.rb

@@ -1,5 +1,12 @@
 class User < ActiveRecord::Base
   has_many :posts, dependent: :destroy
+  has_many :relationships, foreign_key: "follower_id", dependent: :destroy
+  has_many :followed_users, through: :relationships, source: :followed
+
+  has_many :reverse_relationships, foreign_key: "followed_id",
+                                   class_name: "Relationship",
+                                   dependent: :destroy
+  has_many :followers, through: :reverse_relationships, source: :follower
 
   before_save { self.email = email.downcase }
   before_create :create_remember_token
@@ -24,7 +31,19 @@ def User.encrypt(token)
   end
 
   def feed
-    Post.where("user_id = ?", id)
+    Post.from_users_followed_by(self) 
+  end
+
+  def following?(other_user)
+    relationships.find_by(followed_id: other_user.id)
+  end
+
+  def follow!(other_user)
+    relationships.create!(followed_id: other_user.id)
+  end
+
+  def unfollow!(other_user)
+    relationships.find_by(followed_id: other_user.id).destroy
   end
 
   private

app/views/relationships/create.js.erb

@@ -0,0 +1,2 @@
+$("#follow_form").html("<%= escape_javascript(render('users/unfollow')) %>")
+$("#followers").html('<%= @user.followers.count %>')

app/views/relationships/destroy.js.erb

@@ -0,0 +1,2 @@
+$("#follow_form").html("<%= escape_javascript(render('users/follow')) %>")
+$("#followers").html('<%= @user.followers.count %>')

app/views/shared/_stats.html.erb

@@ -0,0 +1,15 @@
+<% @user ||= current_user %>
+<div class="stats">
+  <a href="<%= following_user_path(@user) %>">
+    <strong id="following" class="stat">
+      <%= @user.followed_users.count %>
+    </strong>
+    following
+  </a>
+  <a href="<%= followers_user_path(@user) %>">
+    <strong id="followers" class="stat">
+      <%= @user.followers.count %>
+    </strong>
+    followers
+  </a>
+</div>

app/views/static_pages/home.html.erb

@@ -4,6 +4,9 @@
       <section>
         <%= render 'shared/user_info' %>
       </section>
+      <section>
+        <%= render 'shared/stats' %>
+      </section>
       <section>
         <%= render 'shared/post_form' %>
       </section>

app/views/users/_follow.html.erb

@@ -0,0 +1,5 @@
+<%= form_for(current_user.relationships.build(followed_id: @user.id),
+            remote: true) do |f| %>
+  <div><%= f.hidden_field :followed_id %></div>
+  <%= f.submit "Follow", class: "btn btn-large btn-primary" %>
+<% end %>

app/views/users/_follow_form.html.erb

@@ -0,0 +1,9 @@
+<% unless current_user?(@user) %>
+  <div id="follow_form">
+    <% if current_user.following?(@user) %>
+      <%= render 'unfollow' %>
+    <% else %>
+      <%= render 'follow' %>
+    <% end %>
+  </div>
+<% end %>

app/views/users/_unfollow.html.erb

@@ -0,0 +1,5 @@
+<%= form_for(current_user.relationships.find_by(followed_id: @user.id),
+             html: { method: :delete },
+             remote: true) do |f| %>
+  <%= f.submit "Unfollow", class: "btn btn-large" %>
+<% end %>

app/views/users/show.html.erb

@@ -4,8 +4,12 @@
     <section>
       <h1><%= @user.name %></h1>
     </section>
+    <section>
+      <%= render 'shared/stats' %>
+    </section>
   </aside>
   <div class="span8">
+    <%= render 'follow_form' if signed_in? %>
     <% if @user.posts.any? %>
       <h3>Posts (<%= @user.posts.count %>)</h3>
       <ol class="posts">

app/views/users/show_follow.html.erb

@@ -0,0 +1,20 @@
+<div class="row">
+  <aside class="span4">
+    <section>
+      <h1><%= @user.name %></h1>
+      <span><%= link_to "view my profile", @user %></span>
+      <span><b>Posts:</b> <%= @user.posts.count %></span>
+    </section>
+    <section>
+      <%= render 'shared/stats' %>
+    </section>
+  </aside>
+  <div class="span8">
+    <h3><%= @title %></h3>
+    <% if @users.any? %>
+      <ul class="users">
+        <%= render @users %>
+      </ul>
+    <% end %>
+  </div>
+</div>

config/routes.rb

@@ -3,7 +3,11 @@
   match '/help', to: 'static_pages#help', via: 'get'
   match '/about', to: 'static_pages#about', via: 'get'
 
-  resources :users
+  resources :users do
+    member do
+      get :following, :followers
+    end
+  end
   match '/signup', to: 'users#new', via: 'get'
 
   resources :sessions, only: [:new, :create, :destroy]
@@ -12,6 +16,8 @@
 
   resources :posts, only: [:create, :destroy]
 
+  resources :relationships, only: [:create, :destroy]
+
   # The priority is based upon order of creation: first created -> highest priority.
   # See how all your routes lay out with "rake routes".
 

db/migrate/20140126185610_create_relationships.rb

@@ -0,0 +1,13 @@
+class CreateRelationships < ActiveRecord::Migration
+  def change
+    create_table :relationships do |t|
+      t.integer :follower_id
+      t.integer :followed_id
+
+      t.timestamps
+    end
+    add_index :relationships, :follower_id
+    add_index :relationships, :followed_id
+    add_index :relationships, [:follower_id, :followed_id], unique: true
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20140122232133) do
+ActiveRecord::Schema.define(version: 20140126185610) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -27,6 +27,17 @@
 
   add_index "posts", ["user_id", "created_at"], name: "index_posts_on_user_id_and_created_at", using: :btree
 
+  create_table "relationships", force: true do |t|
+    t.integer  "follower_id"
+    t.integer  "followed_id"
+    t.datetime "created_at"
+    t.datetime "updated_at"
+  end
+
+  add_index "relationships", ["followed_id"], name: "index_relationships_on_followed_id", using: :btree
+  add_index "relationships", ["follower_id", "followed_id"], name: "index_relationships_on_follower_id_and_followed_id", unique: true, using: :btree
+  add_index "relationships", ["follower_id"], name: "index_relationships_on_follower_id", using: :btree
+
   create_table "users", force: true do |t|
     t.string   "email"
     t.string   "name"

lib/tasks/sample_data.rake

@@ -1,34 +1,43 @@
 namespace :db do
 	desc "Fill database with sample data"
   task populate: :environment do
-    User.create!(name: "Adam Morganaki",
-                 email: "[email protected]",
-                 password: "foobar",
-                 password_confirmation: "foobar",
-                 admin: true)
-    User.create!(name: "Kill Clean",
-                 email: "[email protected]",
-                 password: "foobar",
-                 password_confirmation: "foobar",
-                 admin: true)
-    25.times do |n|
-      name  = Faker::Name.name
-      email = "example-#{n+1}@testing.org"
-      password  = "password"
-      User.create!(name: name,
-                   email: email,
-                   password: password,
-                   password_confirmation: password)
-    end
+    make_users
+    make_posts
+    make_relationships
   end
+end
 
-  desc "Fill database with sample data"
-  task populate: :environment do
-    users = User.all(limit: 5)
-    10.times do
-      title = Faker::Lorem.sentence(5)
-      content = Faker::Lorem.sentence(5)
-      users.each { |user| user.posts.create!(title: title, content: content) }
-    end
+def make_users
+  admin = User.create!(name: "Adam Morganaki",
+               email: "[email protected]",
+               password: "foobar",
+               password_confirmation: "foobar",
+               admin: true)
+  99.times do |n|
+    name  = Faker::Name.name
+    email = "example-#{n+1}@testing.org"
+    password  = "password"
+    User.create!(name: name,
+                 email: email,
+                 password: password,
+                 password_confirmation: password)
   end
 end
+
+def make_posts
+  users = User.all(limit: 5)
+  10.times do
+    title = Faker::Lorem.sentence(5)
+    content = Faker::Lorem.sentence(5)
+    users.each { |user| user.posts.create!(title: title, content: content) }
+  end
+end
+
+def make_relationships
+  users = User.all
+  user = users.first
+  followed_users = users[2..50]
+  followers      = users[3..40]
+  followed_users.each { |followed| user.follow!(followed) }
+  followers.each      { |follower| follower.follow!(user) }
+end

test/fixtures/relationships.yml

@@ -0,0 +1,9 @@
+# Read about fixtures at http://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+one:
+  follower_id: 1
+  followed_id: 1
+
+two:
+  follower_id: 1
+  followed_id: 1

test/models/relationship_test.rb

@@ -0,0 +1,7 @@
+require 'test_helper'
+
+class RelationshipTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end