This is my note about friendly forwarding in Rails.

When forwarding to the URL immediately before current one

Use the request.referrer method.

  ...
  def destroy
    @micropost.destroy
    flash[:success] = "Micropost deleted"
    redirect_to request.referrer || root_url
  end
  ...

When forwarding to the URL further before

Store the URL in the session ahead of time.

module SessionsHelper
  ...

  # Redirects to stored location (or to the default).
  def redirect_back_or(default)
    redirect_to(session[:forwarding_url] || default)
    session.delete(:forwarding_url)
  end

  # Stores the URL trying to be accessed.
  def store_location
    session[:forwarding_url] = request.original_url if request.get?
  end
end

request.referrer

• Returns the previous request URL as a String.
• The same as request.headers["HTTP_REFERER"]

original_url

• Returns the original request URL as a String.

# get "/articles?page=2"
request.original_url # => "http://www.example.com/articles?page=2"

References

• The Ruby on Rails Tutorial by Michael Hartl