@bodrovis - Hi Ilya,
Thanks so much for this tutorial, incredibly helpful for the project I am currently working on.
One minor point which my team got stuck on for a couple of hours together around the Google+ OAuth step.
We were trying to run in local host following your exact implementation instructions but continued to get redirect_url, CSRF detected and SSL errors throughout troubleshooting.
2 things worked for us that are worth flagging to other people following:
- Deployed to heroku - this may have been implicit in your instructions but this was only scenario that the specific route matching worked for us
- For local deployment, we had to change our callback url reference in our Google project credentials to localhost vs /127.0.0.1 AND in our omniauth initializer add the line OpenSSL::SSL::VERIFY_PEER = OpenSSL::SSL::VERIFY_NONE if Rails.env.development? to disable SSL certificate verification