Update README.md

Added documentation

README.md

@@ -1,2 +1,143 @@
 # DeviseSocialAuthentication
 Devise authentification with Facebook and Google
+
+### Step 1 - create our new rails application
+create our working space & our new app
+
+```sh
+rails new fb_auth
+cd fb_auth
+```
+
+### Step 2 - Add the Required Gems to the Gemfile
+edit this file ~/fb_auth/GemFile
+
+```ruby
+gem 'devise'
+gem 'omniauth'
+gem 'omniauth-facebook'
+gem 'omniauth-google-oauth2'
+bundle install
+```
+
+### Step 3 - Add Basic Functionality to the Application
+Add some code to your application like this.
+
+```ruby
+rails g scaffold Product name:string price:integer description:text
+rake db:migrate
+```
+
+Edit ~/fb_auth/config/routes.rb, and add the line root 'products#index'
+
+```ruby
+Rails.application.routes.draw do
+  resources :products
+  root 'products#index'
+end
+```
+
+### Step 4 - Set Up Devise
+
+```sh
+rails generate devise:install
+rails generate devise User
+rails g migration AddColumnsToUsers provider uid
+rake db:migrate
+```
+
+Our app now has a basic authentication system, where users can register themselves, and then log in. However, all the pages are still directly accessible. To change this, edit ~/fb_auth/app/controllers/application_controller.rb 
+
+```ruby
+class ApplicationController < ActionController::Base
+  protect_from_forgery with: :exception
+  before_action :authenticate_user!
+end
+```
+
+### Step 5 - Update the Devise Initializer
+
+Edit ~/fb_auth/config/initializers/devise.rb to add the client IDs and secrets at the bottom of the file, just before the end line.
+
+```ruby
+Devise.setup do |config|
+  #Replace example.com with your own domain name
+  config.mailer_sender = '[email protected]'
+
+  require 'devise/orm/active_record'
+  config.case_insensitive_keys = [ :email ]
+  config.strip_whitespace_keys = [ :email ]
+  config.skip_session_storage = [:http_auth]
+  config.stretches = Rails.env.test? ? 1 : 10
+  config.reconfirmable = true
+  config.expire_all_remember_me_on_sign_out = true
+  config.password_length = 8..128
+  config.reset_password_within = 6.hours
+  config.sign_out_via = :delete
+
+  #Add your ID and secret here
+  #ID first, secret second
+  config.omniauth :facebook, "db381dc9990be7e3bc42503d0", "5b0824c2722b65d29965f1a1df"
+end
+```
+
+### Step 6 - Update the User Model
+After editing it, your ~/fb_auth/app/models/user.rb should look like this:
+
+```ruby
+class User < ActiveRecord::Base
+  # Include default devise modules. Others available are:
+  # :confirmable, :lockable, :timeoutable and :omniauthable
+  devise :database_authenticatable, :registerable,
+         :recoverable, :rememberable, :trackable, :validatable,
+         :omniauthable, :omniauth_providers => [:facebook]
+
+  def self.from_omniauth(auth)
+      where(provider: auth.provider, uid: auth.uid).first_or_create do |user|
+        user.provider = auth.provider
+        user.uid = auth.uid
+        user.email = auth.info.email
+        user.password = Devise.friendly_token[0,20]
+      end
+  end
+end
+```
+
+### Step 7 - Add a Controller to Handle the Callback URLs
+
+First, edit ~/fb_auth/config/routes.rb and update the devise_for line to specify the name of the controller that will be handling the callbacks.
+
+```ruby
+Rails.application.routes.draw do
+  devise_for :users, :controllers => { :omniauth_callbacks => "callbacks" }
+  resources :products
+  root 'products#index'
+end
+```
+
+### Step 6 - Add this link to login page or whatever you want.
+<%= link_to "Sign in with Facebook", user_omniauth_authorize_path(:facebook) %>
+
+### For adding others providers you must edit this files:
+>~/fb_auth/config/initializers/devise.rb 
+>~/fb_auth/app/models/user.rb
+>~/fb_auth/app/controllers/callbacks_controller.rb
+
+### Support
+
+Sergio Peralta [email protected]
+
+Please file issues [click here] at Github. 
+
+Copyright (c) 2015 Sergio Peralta. This software is licensed under the MIT License.
+
+Good luck!
+
+[click here]:https://github.com/serpel/DeviseSocialAuthentication/issues
+
+### Fork it
+
+- Create your feature branch (git checkout -b my-new-feature)
+- Commit your changes (git commit -am 'Add some feature')
+- Push to the branch (git push origin my-new-feature)
+- Create a new Pull Request