class Auth0Controller < ApplicationController
  def callback
  end

  def failure
  end
end

class Auth0Controller < ApplicationController
def callback
    # This stores all the user information that came from Auth0
    # and the IdP
    session[:userinfo] = request.env['omniauth.auth']

    # Redirect to the URL you want after successfull auth
    redirect_to '/dashboard'
  end

  def failure
    # show a failure page or redirect to an error page
    @error_msg = request.params['message']
  end
end

Add the shell for the code that will hand the success and failure of the callback
Add the shell for the code that will hand the success and failure of the callback
