Add user following

app/assets/stylesheets/static_pages.css.scss

@@ -139,6 +139,35 @@ aside {
   }
 }
 
+.stats {
+  overflow: auto;
+  a {
+    float: left;
+    padding: 0 10px;
+    border-left: 1px solid $grayLighter;
+    color: gray;
+    &:first-child {
+      padding-left: 0;
+      border: 0;
+    }
+    &:hover {
+      text-decoration: none;
+      color: $blue;
+    }
+  }
+  strong {
+    display: block;
+  }
+}
+
+.user_avatars {
+  overflow: auto;
+  margin-top: 10px;
+  .gravatar {
+    margin: 1px 1px;
+  }
+}
+
 #error_explanation {
   color: #f00;
   ul {

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|
+      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

@@ -1,5 +1,6 @@
 class UsersController < ApplicationController
-  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
 
@@ -40,8 +41,26 @@ class UsersController < ApplicationController
       render 'edit'
     end
   end
+
+    def following
+    @title = "Following"
+    @user = User.find(params[:id])
+    @users = @user.followed_users.paginate(page: params[:page])
+    render 'show_follow'
+  end
+
+  def followers
+    @title = "Followers"
+    @user = User.find(params[:id])
+    @users = @user.followers.paginate(page: params[:page])
+    render 'show_follow'
+  end
+
+
   private
 
+
+
     def user_params
       params.require(:user).permit(:name, :email, :password,
                                    :password_confirmation)

app/models/micropost.rb

@@ -4,4 +4,13 @@ class Micropost < ActiveRecord::Base
   default_scope -> { order('created_at DESC') }
   validates :content, presence: true, length: { maximum: 140 }
   validates :user_id, presence: true
-end
+
+
+  # Returns microposts from the users being followed by the given user.
+  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 +1,6 @@
+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 +1,14 @@
 class User < ActiveRecord::Base
   has_many :microposts, 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
   validates :name, presence: true, length: { maximum: 50 }
@@ -19,8 +28,19 @@ class User < ActiveRecord::Base
   end
 
     def feed
-    # This is preliminary. See "Following users" for the full implementation.
-    Micropost.where("user_id = ?", id)
+    Micropost.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
@@ -29,3 +49,4 @@ class User < ActiveRecord::Base
       self.remember_token = User.encrypt(User.new_remember_token)
     end
 end
+

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

@@ -3,6 +3,9 @@
     <aside class="span4">
       <section>
         <%= render 'shared/user_info' %>
+      </section>
+	        <section>
+        <%= render 'shared/stats' %>
       </section>
       <section>
         <%= render 'shared/micropost_form' %>

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),
+             html: { method: :delete },
+             remote: true) do |f| %>
+  <%= f.submit "Unfollow", class: "btn btn-large" %>
+<% end %>

app/views/users/show.html.erb

@@ -6,9 +6,15 @@
         <%= gravatar_for @user %>
         <%= @user.name %>
       </h1>
+    </section>
+	    <section>
+      <%= render 'shared/stats' %>
     </section>
   </aside>
+
  <div class="span8">
+ <%= render 'follow_form' if signed_in? %>
+ 
     <% if @user.microposts.any? %>
       <h3>Microposts (<%= @user.microposts.count %>)</h3>
       <ol class="microposts">

app/views/users/show_follow.html.erb

@@ -0,0 +1,30 @@
+<% provide(:title, @title) %>
+<div class="row">
+  <aside class="span4">
+    <section>
+      <%= gravatar_for @user %>
+      <h1><%= @user.name %></h1>
+      <span><%= link_to "view my profile", @user %></span>
+      <span><b>Microposts:</b> <%= @user.microposts.count %></span>
+    </section>
+    <section>
+      <%= render 'shared/stats' %>
+      <% if @users.any? %>
+        <div class="user_avatars">
+          <% @users.each do |user| %>
+            <%= link_to gravatar_for(user, size: 30), user %>
+          <% end %>
+        </div>
+      <% end %>
+    </section>
+  </aside>
+  <div class="span8">
+    <h3><%= @title %></h3>
+    <% if @users.any? %>
+      <ul class="users">
+        <%= render @users %>
+      </ul>
+      <%= will_paginate %>
+    <% end %>
+  </div>
+</div>

config/routes.rb

@@ -1,8 +1,14 @@
 SampleApp::Application.routes.draw do
+	  resources :users do
+    member do
+      get :following, :followers
+    end
+  end
   resources :products
   resources :users
   resources :sessions, only: [:new, :create, :destroy]
   resources :microposts, only: [:create, :destroy]
+  resources :relationships, only: [:create, :destroy]
   root  'static_pages#home'
   match '/signup',   to: 'users#new',            via: 'get'
   match '/signin',  to: 'sessions#new',         via: 'get'

db/migrate/20131118215946_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: 20131107052554) do
+ActiveRecord::Schema.define(version: 20131118215946) do
 
   create_table "microposts", force: true do |t|
     t.string   "content"
@@ -29,6 +29,17 @@ ActiveRecord::Schema.define(version: 20131107052554) do
     t.datetime "updated_at"
   end
 
+  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"
+  add_index "relationships", ["follower_id", "followed_id"], name: "index_relationships_on_follower_id_and_followed_id", unique: true
+  add_index "relationships", ["follower_id"], name: "index_relationships_on_follower_id"
+
   create_table "users", force: true do |t|
     t.string   "name"
     t.string   "email"

lib/tasks/sample_data.rake

@@ -1,26 +1,42 @@
 namespace :db do
-
   desc "Fill database with sample data"
   task populate: :environment do
-
-	User.create!(name: "Example User",
-                 email: "example@railstutorial.org",
-                 password: "foobar",
-                 password_confirmation: "foobar")
-    99.times do |n|
-      name  = Faker::Name.name
-      email = "example-#{n+1}@railstutorial.org"
-      password  = "password"
-      User.create!(name: name,
-                   email: email,
-                   password: password,
-                   password_confirmation: password)
-    end
-    users = User.all(limit: 6)
-    50.times do
-      content = Faker::Lorem.sentence(5)
-      users.each { |user| user.microposts.create!(content: content) }
-    end
-end	
+    make_users
+    make_microposts
+    make_relationships
+  end
+end
+
+def make_users
+  admin = User.create!(name:     "Example User",
+                       email:    "example@railstutorial.org",
+                       password: "foobar",
+                       password_confirmation: "foobar",
+                       admin: true)
+  99.times do |n|
+    name  = Faker::Name.name
+    email = "example-#{n+1}@railstutorial.org"
+    password  = "password"
+    User.create!(name:     name,
+                 email:    email,
+                 password: password,
+                 password_confirmation: password)
+  end
 end
-
+
+def make_microposts
+  users = User.all(limit: 6)
+  50.times do
+    content = Faker::Lorem.sentence(5)
+    users.each { |user| user.microposts.create!(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

spec/models/relationship_spec.rb

@@ -0,0 +1,5 @@
+require 'spec_helper'
+
+describe Relationship do
+  pending "add some examples to (or delete) #{__FILE__}"
+end