adds omniauth basic authentication process with Twitter, including an intermediate step to ask the user for her email if not provided by the OAuth provider - Twitter, for instance

config/initializers/devise.rb

@@ -239,6 +239,7 @@ Devise.setup do |config|
   # Add a new OmniAuth provider. Check the wiki for more information on setting
   # up on your models and hooks.
   # config.omniauth :github, 'APP_ID', 'APP_SECRET', scope: 'user,public_repo'
+  config.omniauth :twitter, Rails.application.secrets.twitter_key, Rails.application.secrets.twitter_secret
 
   # ==> Warden configuration
   # If you want to use other strategies, that are not supported by Devise, or

config/initializers/omniauth.rb

@@ -1,4 +0,0 @@
-Rails.application.config.middleware.use OmniAuth::Builder do
-  provider :developer unless Rails.env.production?
-  provider :twitter, Rails.application.secrets.twitter_key, Rails.application.secrets.twitter_secret
-end

config/locales/devise.es.yml

@@ -55,4 +55,4 @@ es:
       not_locked: "no estaba bloqueado."
       not_saved:
         one: "1 error impidió que este %{resource} fuera guardado:"
-        other: "%{count} errores impidieron que este %{resource} fuera guardado:"
+        other: "%{count} errores impidieron que este %{resource} fuera guardado:"

config/locales/en.yml

@@ -148,3 +148,9 @@ en:
       all: "You are not authorized to %{action} %{subject}."
   welcome:
     last_debates: Last debates
+  omniauth:
+    finish_signup:
+      title: Add Email
+    twitter:
+      sign_in: Sign in with Twitter
+    or: or

config/locales/es.yml

@@ -148,3 +148,9 @@ es:
       all: "No tienes permiso para realizar la acción '%{action}' sobre %{subject}."
   welcome:
     last_debates: Últimos debates
+  omniauth:
+    finish_signup:
+      title: Añade tu email
+    twitter:
+      sign_in: Inicia sessión con Twitter
+    or: o

config/routes.rb

@@ -1,10 +1,19 @@
 Rails.application.routes.draw do
-  devise_for :users, controllers: { registrations: 'users/registrations' }
+  devise_for :users, controllers: {
+                       registrations: 'users/registrations',
+                       omniauth_callbacks: 'users/omniauth_callbacks'
+                     }
   devise_for :organizations, class_name: 'User',
              controllers: {
                registrations: 'organizations/registrations',
-               sessions: 'devise/sessions'
-             }
+               sessions: 'devise/sessions',
+             },
+             skip: [:omniauth_callbacks]
+
+  devise_scope :user do
+    get :finish_signup, to: 'users/registrations#finish_signup'
+    patch :do_finish_signup, to: 'users/registrations#do_finish_signup'
+  end
 
   # The priority is based upon order of creation: first created -> highest priority.
   # See how all your routes lay out with "rake routes".