Rails error resource_name - devise help routing and rendering

Question

I am trying to render the login view for the Devise gem but I get an error, below is the code I currently have:

This is my views/users/shared/_links.html.erb:

<%- if controller_name != 'sessions' %>
  <%= link_to "Sign in", new_session_path(resource_name) %><br />
<% end -%>

<%- if devise_mapping.registerable? && controller_name != 'registrations' %>
  <%= link_to "Sign up", new_registration_path(resource_name) %><br />
<% end -%>

<%- if devise_mapping.recoverable? && controller_name != 'passwords' %>
  <%= link_to "Forgot your password?", new_password_path(resource_name) %><br />
<% end -%>

<%- if devise_mapping.confirmable? && controller_name != 'confirmations' %>
  <%= link_to "Didn't receive confirmation instructions?", new_confirmation_path(resource_name) %><br />
<% end -%>

<%- if devise_mapping.lockable? && resource_class.unlock_strategy_enabled?(:email) && controller_name != 'unlocks' %>
  <%= link_to "Didn't receive unlock instructions?", new_unlock_path(resource_name) %><br />
<% end -%>

<%- if devise_mapping.omniauthable? %>
  <%- resource_class.omniauth_providers.each do |provider| %>
    <%= link_to "Sign in with #{provider.to_s.titleize}", omniauth_authorize_path(resource_name, provider) %><br />
  <% end -%>
<% end -%>

And my config/routes.rb:

Densidste::Application.routes.draw do
  match 'user/edit' => 'users#edit', :as => :edit_current_user

  match 'signup' => 'devise/users#new', :as => :signup

  match 'logout' => 'devise/sessions#destroy', :as => :logout

  devise_for :users do
    get "login", :to => "devise/sessions#new"
  end

  resources :sessions

  resources :users

  devise_for :users

  resources :aktivs

  resources :taggingposts

  resources :tags

  resources :kommentares

  resources :posts

  # You can have the root of your site routed with "root"
  # just remember to delete public/index.html.
  root :to => "public#index"
end

And in my application layout:

<%= render("users/shared/links") %>

I get the following error in the _links.html.erb partial:

NameError in Public#index

Showing C:/Rails/Densidste/app/views/users/shared/_links.erb where line #2 raised:

undefined local variable or method `resource_name' for #<#<Class:0x5db76c0>:0x5db6538>

Extracted source (around line #2):

1: <%- if controller_name != 'sessions' %>
2:   <%= link_to "Sign in", new_session_path(resource_name) %><br />
3: <% end -%>
4: 
5: <%- if devise_mapping.registerable? && controller_name != 'registrations' %>

Trace of template inclusion: app/views/public/index.html.erb

Rails.root: C:/Rails/Densidste

Finally, in my application controller I have the following:

before_filter :resource_name
  def resource_name
    if user_signed_in?
      current_user.name
    else
      :user
    end
  end
end

Any help would be much appreciated, thanks!

Answer 1

resource_name is defined in the Devise generated controllers. I don't think you can include those shared links in the application layout, I think they are intended for use on the devise forms (registration,sessions,passwords,confirmations,etc), which are rendered by devise controllers.

If you want to have little login/out snippets in every page, you might want to consider writing those links yourself. For instance, if your object that you're using devise for is user, you could write this:

<%= link_to "Sign in", new_session_path(:user) %><br />

the resource_name is just the Devise abstraction for the resource you're using. I expect that if you're making this link, you know which of your authenticated objects you want to login as, so you can specify it explicitly. You could aslo run rake routes | grep sessions and see what the name of the path is and use that directly. For example:

<%= link_to "Sign in", new_user_session_path %><br />