Routes stopped working when upgrading Rails 3.0 to 3.1

问题

I am using Ruby 1.8.7 with Rails 3.1. My application worked fine in Rails 3.0 but when I bumped it up to Rails 3.1.4, all my url helpers broke!

After Googling like a mad man the past 2 days, I have given up and the time has come to seek help. I don't believe the problem is with my routes.rb file but something more on the view/helper side.

I have the following in my routes.rb:

resources :sessions

In my homepage view I have the following link_to, which errors out:

<%= link_to "Login", new_session_path %>

When I do rake routes, I get the following output, so the path exists:

          sessions GET    /sessions(.:format)          {:controller=>"sessions", :action=>"index"}
                   POST   /sessions(.:format)          {:controller=>"sessions", :action=>"create"}
       new_session GET    /sessions/new(.:format)      {:controller=>"sessions", :action=>"new"}
      edit_session GET    /sessions/:id/edit(.:format) {:controller=>"sessions", :action=>"edit"}
           session GET    /sessions/:id(.:format)      {:controller=>"sessions", :action=>"show"}
                   PUT    /sessions/:id(.:format)      {:controller=>"sessions", :action=>"update"}
                   DELETE /sessions/:id(.:format)      {:controller=>"sessions", :action=>"destroy"}

When I go to /sessions/new in my browser, the page loads so again, the route exists, but it errors out on a _path based url:

<%= form_tag sessions_path, :method => :post do -%>

The error I get is as follows:

ActionView::Template::Error (undefined local variable or method `sessions_path' for #<#<Class:0x109cb8900>:0x109cab840>):

It has to be something with the url_for helper as the routes do exist. What else should I look for?

UPDATE 1:

I added the following inside application_helper.rb:

include Rails.application.routes.url_helpers

Now when I get the following error:

In order to use #url_for, you must include routing helpers explicitly. For instance, `include Rails.application.routes.url_helpers

Isn't that is what I just did?

Update 2:

The following worked as MrYoshiji suggested:

Rails.application.routes.url_helpers.sessions_path

Update 3:

I got sessions_path working again by removing some old Rails 2 plugins in vendor directory.

回答1:

Removed some Rails 2 plugins in vendor/plugins did the trick.

来源：https://stackoverflow.com/questions/14778995/routes-stopped-working-when-upgrading-rails-3-0-to-3-1

标签

ruby-on-rails

ruby-on-rails-3.1

routes

view-helpers

url-for