Redirect loop with Devise after_sign_in_path_for

Question

I'm having a bit of a noob issue. I wanted to get devise to redirect to the last page the user visited. So I did the following...

def after_sign_in_path_for(resource)
    request.referer
end

Works great...except if the user is actually logging in through the original form which causes a redirect loop.

I tried

def after_sign_in_path_for(resource)
   if (request.referer == "/users/sign_in")
  :pages_home
 else
  request.referer
 end

end

But thats not working, most likely because I have no idea what request.referer is actually returning when it encounters the original user login page (www.example.com/users/sign_in).

Any ideas?

tldr; Using devise, I want to redirect to the page logged in from (i.e /blog/4) unless the page is /users/sign_in

SOLVED:

Matchu was right. The request.referer was returning the domain as well...

http://example.com/users/sign_in

(note: no www prefix)

I'm still interested in an alternative to request.referer if its an insecure or inefficient way.

Answer 1

Don't redirect to referrers - it's generally a bad idea.

Instead, pass a next value across in the query-string or form-data. Perhaps use something like:

def after_sign_in_path_for(resource)
  params[:next] || super
end

When a user tries to visit a page requiring authentication (e.g., /admin/posts/3/edit) the authentication before_filter issues a redirect_to new_session_url(:next => request.path). Then code up the login action and view to preserve the :next query-string parameter.

Answer 2

How about this:

def after_sign_in_path_for(resource)
  sign_in_url = url_for(:action => 'sign_in', :controller => 'users', :only_path => false, :protocol => 'http')  
  if (request.referer == sign_in_url)
    super
  else
    request.referer
  end
end

Answer 3

I took Justice's answer and changed it to use sessions instead.

As far as I can see, sessions are simpler then adding the url as param, but they might behave unexpected when a user is browsing a site in multiple tabs, for example. Using sessions is less RESTfull, but simpler and cleaner.

When using CanCan, setting the redirect-path can be done in a central place: the place that handles the "access denied" exceptions:

  rescue_from CanCan::AccessDenied do |exception|
    if current_user.nil?
      session[:next] = request.fullpath
      puts session[:next]
      redirect_to new_user_session_path, :alert => exception.message
    else
      render :file => "#{Rails.root}/public/403.html", :status => 403
    end
  end

But you can set this anywhere, actually:

 def edit
   if current_user.roles[:moderator].nil?
     session[:next] = "/contact"
     redirect_to new_user_session_path, :alert => "please contact the moderator for access"
   end
   # ...
 end

Then, in ApplicationController, you can re-use that session value. Make sure to remove it too, though.

  def after_sign_in_path_for(resource)
    path = ''
    if session[:next]
      path = session[:next]
      session[:next] = nil
    else
      path = super
    end

    path
  end