Add user following

app/assets/javascripts/relationships.coffee

+# Place all the behaviors and hooks related to the matching controller here.
+# All this logic will automatically be available in application.js.
+# You can use CoffeeScript in this file: http://coffeescript.org/

app/assets/stylesheets/custom.scss

@@ -164,6 +164,45 @@ aside {
   margin-top: 15px;
 }
 
+
+.stats {
+  overflow: auto;
+  margin-top: 0;
+  padding: 0;
+  a {
+    float: left;
+    padding: 0 10px;
+    border-left: 1px solid $gray-lighter;
+    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;
+  }
+  a {
+    padding: 0;
+  }
+}
+
+.users.follow {
+  padding: 0;
+}
+
 /* forms */ 
 input, textarea, select, .uneditable-input {
   border: 1px solid #bbb;

app/assets/stylesheets/relationships.scss

+// Place all the styles related to the Relationships controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: http://sass-lang.com/

app/controllers/relationships_controller.rb

+class RelationshipsController < ApplicationController
+  before_action :logged_in_user
+
+  def create
+    user = User.find(params[:followed_id])
+    current_user.follow(user)
+    # redirect_to 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)
+    # redirect_to user
+    respond_to do |format|
+      format.html { redirect_to @user }
+      format.js
+    end
+  end
+end

app/controllers/users_controller.rb

@@ -55,6 +55,20 @@ class UsersController < ApplicationController
     redirect_to users_url
   end
 
+  def following
+    @title = 'Following'
+    @user  = User.find(params[:id])
+    @users = @user.following.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
 
   # comment

app/helpers/relationships_helper.rb

+module RelationshipsHelper
+end

app/models/relationship.rb

+class Relationship < ApplicationRecord
+  belongs_to :follower, class_name: 'User'
+  belongs_to :followed, class_name: 'User'
+  validates :follower_id, presence: true
+  validates :follower_id, presence: true
+end

app/models/user.rb

 # comment
 class User < ApplicationRecord
   has_many :microposts, dependent: :destroy
+  has_many :active_relationships,  class_name: 'Relationship',
+                                    foreign_key: 'follower_id',
+                                    dependent:  :destroy
+
+  has_many :passive_relationships, class_name: 'Relationship',
+                                    foreign_key: 'followed_id',
+                                    dependent:  :destroy
+  has_many :following, through: :active_relationships, source: :followed
+  has_many :followers, through: :passive_relationships, source: :follower
   attr_accessor :remember_token, :activation_token, :reset_token # we don't wan't to save this attribute to database
   before_save   :downcase_email # before_save { email.downcase! }
   before_create :create_activation_digest
@@ -80,7 +89,29 @@ class User < ApplicationRecord
   # See 'Following users' for the full implementation.
 
   def feed
-    Micropost.where('user_id = ?', id)   # self.id
+    # Micropost.where('user_id = ?', id)   # self.id
+    # Micropost.where("user_id IN (?) OR user_id = ? ", following_ids,id)
+    # Micropost.where("user_id IN (:following_ids) OR user_id = :user_id",
+    #                 following_ids: following_ids, user_id: id)
+    following_ids = "SELECT followed_id FROM relationships
+                      WHERE follower_id = :user_id"
+    Micropost.where("user_id IN (#{following_ids})
+                      OR user_id = :user_id", user_id: id)
+  end
+
+  # Follows a user.
+  def follow(other_user)
+    following << other_user
+  end
+
+  # Unfollows a user.
+  def unfollow(other_user)
+    following.delete(other_user)
+  end
+
+  # Returns true if the current user is following the other user.
+  def following?(other_user)
+    following.include?(other_user)
   end
 
   private

app/views/relationships/create.js.erb

+$("#follow_form").html("<%= escape_javascript(render('users/unfollow')) %>");
+$("#followers").html('<%= @user.followers.count %>');
\ No newline at end of file

app/views/relationships/destroy.js.erb

+$("follow_form").html("<%= escape_javascript(render('users/follow')) %>");
+$("followers").html('<%= @user.followers.count %>');
\ No newline at end of file

app/views/shared/_stats.html.erb

+<% @user ||= current_user %>
+<div class='stats'>
+  <a href="<%=following_user_path(@user) %>">
+    <strong id='following' class='stat'>
+      <%= @user.following.count %>
+    </strong>
+    following
+  </a>
+
+  <a href="<%= followers_user_path(@user) %>">
+    <strong id='followers' class'stat'>
+      <%= @user.followers.count %>
+    </strong>
+    followers
+  </a>
+</div>
\ No newline at end of file

app/views/static_pages/home.html.erb

@@ -6,6 +6,9 @@
       <section class='user_infor'>
         <%= render 'shared/user_info' %>
       </section>
+      <section class'stats'>
+        <%= render 'shared/stats' %>
+      </section>
       <section class='micropost_form'>
         <%= render 'shared/micropost_form' %>
       </section>

app/views/users/_follow.html.erb

+<%= form_for(current_user.active_relationships.build, remote: true) do |f| %>
+  <div><%= hidden_field_tag :followed_id, @user.id %></div>
+  <%= f.submit 'Follow', class: 'btn btn-primary' %>
+<% end %>
\ No newline at end of file

app/views/users/_follow_form.html.erb

+<% unless current_user?(@user) %>
+  <div id='follow_form'>
+    <% if current_user.following?(@user) %>
+      <%= render 'unfollow' %>
+    <% else %>
+      <%= render 'follow' %>
+    <% end %>
+  </div>
+<% end %>
\ No newline at end of file

app/views/users/_unfollow.html.erb

+<%= form_for(current_user.active_relationships.find_by(followed_id: @user.id),
+          html: { method: :delete }, remote: true ) do |f| %>
+  <%= f.submit 'Unfollow', class: 'btn' %>
+<% end %>
\ No newline at end of file

app/views/users/show.html.erb

@@ -7,9 +7,13 @@
         <%= @user.name %>
       </h1>
     </section> 
+    <section class='stats'>
+      <%= render 'shared/stats' %>
+    </section>
   </aside>
 
   <div class='col-md-8'>
+    <%= render 'follow_form' if logged_in? %>
     <% if @user.microposts.any? %>
       <h3>Microposts (<%= @user.microposts.count %>)</h3>
       <ol class='micropost'>

app/views/users/show_follow.html.erb

+<% provide(:title, @title) %>
+<div class='row'>
+  <aside class='col-md-4'>
+    <section class='user_info'>
+      <%= 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 class='stats'>
+      <%= 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='col-md-8'>
+    <h3><%= @title %></h3>
+    <% if @users.any? %>
+      <ul class='user follow'>
+        <%= render @users %>
+      </ul>
+      <%= will_paginate %>
+    <% end %>
+  </div>
+</div>
\ No newline at end of file

config/application.rb

@@ -14,5 +14,8 @@ module SampleApp
     # Settings in config/environments/* take precedence over those specified here.
     # Application configuration should go into files in config/initializers
     # -- all .rb files in that directory are automatically loaded.
+
+    # Include the authenticity token in remote form.
+    config.action_view.embed_authenticity_token_in_remote_forms = true
   end
 end

config/routes.rb

@@ -8,8 +8,14 @@ Rails.application.routes.draw do
   get '/login',     to: 'sessions#new'
   post '/login',    to: 'sessions#create'
   delete '/logout', to: 'sessions#destroy'
-  resources :users
+  # resources :users
+  resources :users do
+    member do
+      get :following, :followers
+    end
+  end
   resources :account_activations, only: [:edit]
   resources :password_resets,     only: [:new, :create, :edit, :update]
   resources :microposts,          only: [:create, :destroy]
+  resources :relationships,       only: [:create, :destroy]
 end

db/migrate/20180605031002_create_relationships.rb

+class CreateRelationships < ActiveRecord::Migration[5.1]
+  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

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20180605023125) do
+ActiveRecord::Schema.define(version: 20180605031002) do
 
   create_table "microposts", force: :cascade do |t|
     t.text "content"
@@ -22,6 +22,16 @@ ActiveRecord::Schema.define(version: 20180605023125) do
     t.index ["user_id"], name: "index_microposts_on_user_id"
   end
 
+  create_table "relationships", force: :cascade do |t|
+    t.integer "follower_id"
+    t.integer "followed_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["followed_id"], name: "index_relationships_on_followed_id"
+    t.index ["follower_id", "followed_id"], name: "index_relationships_on_follower_id_and_followed_id", unique: true
+    t.index ["follower_id"], name: "index_relationships_on_follower_id"
+  end
+
   create_table "users", force: :cascade do |t|
     t.string "name"
     t.string "email"

db/seeds.rb

@@ -21,11 +21,22 @@ User.create!(name:  'Example User',
   User.create!(name:  name,
                email: email,
                password:              password,
-               password_confirmation: password)
+               password_confirmation: password,
+               activated: true,
+               activated_at: Time.zone.now)
 end
 
+# Microposts
 users = User.order(:created_at).take(6)
 50.times do
   content = Faker::Lorem.sentence(5)
   users.each { |user| user.microposts.create!(content: content) }
 end
+
+# Following relatioships
+users = User.all
+user  = users.first
+following = users[2..50]
+followers = users[3..40]
+following.each { |followed| user.follow(followed) }
+followers.each { |follower| follower.follow(user) }

test/controllers/relationships_controller_test.rb

+require 'test_helper'
+
+class RelationshipsControllerTest < ActionDispatch::IntegrationTest
+  # test "the truth" do
+  #   assert true
+  # end
+end

test/fixtures/relationships.yml

+# 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

+require 'test_helper'
+
+class RelationshipTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end