Set up google auth

.config.reek

@@ -9,6 +9,10 @@ UncommunicativeModuleName:
   exclude:
   - Room538
 
+UncommunicativeMethodName:
+  accept:
+    - google_oauth2
+
 LongParameterList:
   max_params: 4
 

Gemfile

@@ -13,6 +13,7 @@ gem 'devise'
 gem 'font-awesome-rails'
 gem 'jbuilder', '~> 2.5'
 gem 'jquery-rails'
+gem 'omniauth-google-oauth2'
 gem 'omniauth-vkontakte'
 gem 'pg', '~> 0.18'
 gem 'public_activity'

Gemfile.lock

@@ -175,6 +175,11 @@ GEM
     omniauth (1.6.1)
       hashie (>= 3.4.6, < 3.6.0)
       rack (>= 1.6.2, < 3)
+    omniauth-google-oauth2 (0.5.0)
+      jwt (~> 1.5)
+      multi_json (~> 1.3)
+      omniauth (>= 1.1.1)
+      omniauth-oauth2 (>= 1.3.1)
     omniauth-oauth2 (1.4.0)
       oauth2 (~> 1.0)
       omniauth (~> 1.2)
@@ -366,6 +371,7 @@ DEPENDENCIES
   launchy
   letter_opener
   listen (~> 3.0.5)
+  omniauth-google-oauth2
   omniauth-vkontakte
   overcommit
   pg (~> 0.18)
@@ -392,4 +398,4 @@ DEPENDENCIES
   web-console (>= 3.3.0)
 
 BUNDLED WITH
-   1.14.6
+   1.15.1

app/controllers/users/omniauth_callbacks_controller.rb

@@ -13,6 +13,18 @@ def vkontakte
       end
     end
 
+    def google_oauth2
+      auth = request.env['omniauth.auth']
+      @user = User.from_omniauth(auth)
+      if @user.persisted?
+        sign_in_and_redirect @user, event: :authentication # this will throw if @user is not activated
+        set_flash_message(:notice, :success, kind: 'Google') if is_navigational_format?
+      else
+        session['devise.google_data'] = auth
+        redirect_to new_user_registration_url
+      end
+    end
+
     def failure
       redirect_to root_path
     end

app/models/user.rb

@@ -9,7 +9,7 @@ class User < ApplicationRecord
 
   devise :database_authenticatable, :registerable,
          :recoverable, :rememberable, :trackable, :validatable,
-         :omniauthable, omniauth_providers: [:vkontakte]
+         :omniauthable, omniauth_providers: [:google_oauth2, :vkontakte]
 
   validates :name, presence: true
 

app/views/devise/registrations/new.html.slim

@@ -4,6 +4,7 @@
 h2.text-center Sign up
 
 .omniauth-links
+= link_to "Sign up with #{fa_icon('google')}".html_safe, user_google_oauth2_omniauth_authorize_path, class: 'omniauth-link'
   = link_to "Sign up with #{fa_icon('vk')}".html_safe, user_vkontakte_omniauth_authorize_path, class: 'omniauth-link'
 
 = simple_form_for(resource, as: resource_name, url: registration_path(resource_name), defaults: { required: true, label: false }) do |f|

app/views/devise/sessions/new.html.slim

@@ -4,6 +4,7 @@
 h2.text-center Sign in
 
 .omniauth-links
+  = link_to "Sign in with #{fa_icon('google')}".html_safe, user_google_oauth2_omniauth_authorize_path, class: 'omniauth-link'
   = link_to "Sign in with #{fa_icon('vk')}".html_safe, user_vkontakte_omniauth_authorize_path, class: 'omniauth-link'
 
 = simple_form_for(resource, as: resource_name, url: session_path(resource_name)) do |f|

config/initializers/devise.rb

@@ -254,6 +254,7 @@
                   scope: 'email',
                   lang: 'en',
                   display: 'popup'
+  config.omniauth :google_oauth2, ENV['GOOGLE_CLIENT_ID'], ENV['GOOGLE_CLIENT_SECRET'], {}
 
   # ==> Warden configuration
   # If you want to use other strategies, that are not supported by Devise, or