Question

I am having a problem. I can’t delete kategoris.

Rake routes:

       admin_kategoris GET    /admin/kategoris(.:format)               {:action=
>"index", :controller=>"admin/kategoris"}
                        POST   /admin/kategoris(.:format)              {:action=
>"create", :controller=>"admin/kategoris"}
     new_admin_kategori GET    /admin/kategoris/new(.:format)          {:action=
>"new", :controller=>"admin/kategoris"}
    edit_admin_kategori GET    /admin/kategoris/:id/edit(.:format)     {:action=
>"edit", :controller=>"admin/kategoris"}
         admin_kategori GET    /admin/kategoris/:id(.:format)          {:action=
>"show", :controller=>"admin/kategoris"}
                        PUT    /admin/kategoris/:id(.:format)          {:action=
>"update", :controller=>"admin/kategoris"}
                        DELETE /admin/kategoris/:id(.:format)          {:action=
>"destroy", :controller=>"admin/kategoris"}

My kategori index view:

<% @kategoris.each do |kategori| %>
  <tr>
    <td><%= kategori.name %></td>
    <td><%= link_to 'show', {:action => 'show', :id => kategori.id}, :class => 'action show' %></td>
    <td><%= link_to 'edit', {:action => 'edit', :id => kategori.id}, :class => 'action edit' %></td>
    <td><td><%= link_to 'slet', {:action => 'destroy', :id => kategori.id, :method => :delete}, :class => 'action destroy' %></td></td>
  </tr>
<% end %>

My kategori controller:

 def destroy
    @kategori = Kategori.find(params[:id])
    @kategori.destroy

    respond_to do |format|
      format.html { redirect_to(kategoris_url) }
      format.xml  { head :ok }
    end
  end

My routes.rb:

namespace :admin do
resources :kategoris
end

I get following error when I press slet (Delete):

Started GET "/admin/kategoris/1?method=destroy" for 127.0.0.1 at 2011-03-05 20:0
8:57 +0100
  Processing by Admin::KategorisController#show as HTML
  Parameters: {"method"=>"destroy", "id"=>"1"}
  ←[1m←[36mKategori Load (1.0ms)←[0m  ←[1mSELECT `kategoris`.* FROM `kategoris`
WHERE (`kategoris`.`cached_slug` = '1') LIMIT 1←[0m
  ←[1m←[35mSQL (1.0ms)←[0m  SELECT sluggable_id FROM slugs WHERE ((slugs.sluggab
le_type = 'Kategori' AND slugs.name = '1' AND slugs.sequence = 1))
  ←[1m←[36mKategori Load (0.0ms)←[0m  ←[1mSELECT `kategoris`.* FROM `kategoris`
WHERE (`kategoris`.`id` = 1) LIMIT 1←[0m
Rendered admin/kategoris/show.html.erb within layouts/application (5.0ms)
Completed   in 166ms

ActionView::Template::Error (No route matches {:action=>"edit", :controller=>"ka
tegoris", :id=>#<Kategori id: 1, name: "Elektronik", created_at: "2011-02-17 04:
18:11", updated_at: "2011-02-17 04:18:11", cached_slug: "">}):
    6: </p>
    7:
    8:
    9: <%= link_to 'Edit', edit_kategori_path(@kategori) %> |
    10: <%= link_to 'Back', admin_kategoris_path %>
  app/views/admin/kategoris/show.html.erb:9:in `_app_views_admin_kategoris_show_
html_erb__679400070_47327076__118033797'
  app/controllers/admin/kategoris_controller.rb:18:in `show'

Rendered C:/Ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.0.3/lib/action_dispatc
h/middleware/templates/rescues/_trace.erb (1.0ms)
Rendered C:/Ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.0.3/lib/action_dispatc
h/middleware/templates/rescues/_request_and_response.erb (4.0ms)
Rendered C:/Ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.0.3/lib/action_dispatc
h/middleware/templates/rescues/template_error.erb within rescues/layout (57.0ms)

My edit link works.

Answer 1

When using Rails’ RESTful actions, the destroy method is invoked by a DELETE request (as indicated by the “DELETE” at the beginning of your rake routes output), not by a GET request (which is the default unless you specify otherwise). So, you need to specify this in your link:

<td><%= link_to 'slet', {:action => 'destroy', :id => kategori.id}, :method => :delete, :class => 'action destroy' %></td>

This could be simplified to:

<td><%= link_to 'slet', admin_kategori_path(kategori), :method => :delete, :class => 'action destroy' %></td>

since admin_kategori is a named route that leads to the correct URL, and using the DELETE method will automatically call the destroy action (since that’s what the routes say to do).

[Update]

It’s also possible that you don’t have your UJS set up properly. You need to:

1. make sure the rails.js script tag (and any libraries it may depend on, like Prototype or jQuery depending on your setup) is included in your layout, and
2. make sure you’re outputting csrf_meta_tag in the head of your layout. If you’re not, it will not work