returning after omniauth

example.haml

# Link to /sign-in/:provider?return_to=current_page in your view. This example shows auth using Twitter in a HAML view
%a{ :href => "/sign-in/twitter?return_to=" + request.env['PATH_INFO'] }

routes.rb

# Add this to your routes.rb file
match "/sign-in/:provider" => "sessions#sign_in"

sessions_controller.rb

# Add this to your sessions controller.
def sign_in
  session[:return_to] = params[:return_to]
  redirect_to "/auth/" + params[:provider]
end