Devise AJAX user authentication doesn't redirect - ruby-on-rails

Question

I have a link in my application.html.erb file
<%= link_to 'Sprzedaż', sell_path, remote: true %>
In the controller I authenticate user with before_action :authenticate_user!. Below is my authenticate_user! method.
protected
def authenticate_user!
if user_signed_in?
super
else
respond_to do |format|
format.js { render nothing: true, status: :unauthorized }
format.html { redirect_to root_path, :alert => 'Aby przejść do tej strony, musisz być zalogowany.' }
end
end
end
Basically it works correctly if the user isn't authorized. If the user has enabled Javascript it shows nice notification, and if the user hasn't enabled Javascript it shows alert and redirect to root_path which is good. The problem is that when the user is signed in and click the link nothing happens. It should redirect to the sell_path.
This is my ItemsController
class ItemsController < ApplicationController
before_action :authenticate_user!
def sell
#user = current_user
#items = JSON.parse(HTTParty.get("http://steamcommunity.com/profiles/#{#user.uid}/inventory/json/730/2?l=polish").body)
end
end
This is my ApplicationController
class ApplicationController < ActionController::Base
# Prevent CSRF attacks by raising an exception.
# For APIs, you may want to use :null_session instead.
protect_from_forgery with: :exception
before_action :steam_informations
def steam_informations
#steam = session[:steam]
end
protected
def authenticate_user!
if user_signed_in?
super
else
respond_to do |format|
format.js { render nothing: true, status: :unauthorized }
format.html { redirect_to root_path, :alert => 'Aby przejść do tej strony, musisz być zalogowany.' }
end
end
end
end

Answer 1

You are trying to override helpers which defined in runtime. This is not how you must to do it.
In your case I recommend you to define for example authenticate! method like this:
def authenticate!
return true if user_signed_in?
respond_to do |format|
format.js { render nothing: true, status: :unauthorized }
format.html { redirect_to root_path, :alert => 'Aby przejść do tej strony, musisz być zalogowany.' }
end
end
This method will do nothing if user signed in and redirect to root page if user not signed in. Just define this method in ApplicationController and then use before_filter :authenticate! hook to execute it.
When before_filter \ before_action method returns false - rails won't execute your action. And if return true or just return - rails will execute action after hooks like authenticate! and render your views. To make it clear I'll show you some examples.
class FooController << ApplicationController
before_filter :dead_hook, only: :index
before_filter :nice_hook, only: :show
def index
# this action will be never executed because dead_hook method returns false.
end
def show
# this action will be executed right after nice_hook method because of 'return true' command in nice_hook method
end
def dead_hook
return false
end
def nice_hook
return true
end
end
Another way to do just like you trying to do - monkey-patch devise helper. You can do it like this:
module Devise
module Controllers
module Helpers
def authenticate_user!
# implement your logic here
end
end
end
end
Here you can check out whats going on in devise helpers:
Github Devise Helpers source code
Just for clarification: there is no difference between before_filter and before_action. Feel free to use any of them. before_action newer but before_filter not deprecated.