Question

I have been following the Railscast #270 found Rails Cast #270 about implementing Authentication in Rails 3.1. What I would like to do is have the ability in my templates to have different links displayed if a user is logged in. It should look something like this.

If user logged in
  Display link to Profile
  Display logout
If user logged out
 Display link to register
 Display link to login

I think I can figure out the link to various places from theRailsTutorial, but I’m stuck on how to tell if a user is signed in or not.

Using the rails tutorial I found this snippet

 <% if signed_in? %>
     <li><%= link_to "Profile", current_user %> sfsdfsdf</li>
 <% end %>

Which doesn’t work when I put the following in my sessions helper:

    def signed_in?
      !@current_user.nil?  
end

How would you make this work?

Answer 1

Use current_user.

so just

 <% if current_user %>
     <li><%= link_to "Profile", current_user %> sfsdfsdf</li>
 <% end %>

btw in HAML that would be just

 -if current_user
   %li= 
     link_to "Profile", current_user, sfsdfsdf

(the ends get implied – both for the HTML <li> tag (i.e. the </li>) AND for the ruby if statement!)
For anyone not using HAML this should wet your appetite 🙂

current_user itself uses @current_user and it gets set up in your application controller as in:

  helper_method :current_user

  private

  def current_user
    @current_user ||= User.find(session[:user_id]) if session[:user_id]
  end