feat: kickstart google callbacks

app/controllers/google/callbacks_controller.rb

@@ -0,0 +1,18 @@
+class Google::CallbacksController < ApplicationController
+  def handle_response
+    redirect_to '/'
+  end
+
+  private
+
+  def oauth_client
+    app_id = GlobalConfigService.load('GOOGLE_OAUTH_CLIENT_ID', nil)
+    app_secret = GlobalConfigService.load('GOOGLE_OAUTH_CLIENT_SECRET', nil)
+
+    ::OAuth2::Client.new(app_id, app_secret, {
+                           site: 'https://oauth2.googleapis.com',
+                           authorize_url: 'https://accounts.google.com/o/oauth2/auth',
+                           token_url: '/token'
+                         })
+  end
+end