understanding path_prefix in restful routes

Hi all,

I have a hard time understanding path_prefix in restful routes.

My urls should always start with the id of a club since my site is
club oriented eg: www.clubsite.com/zero/ where zero is the club

I have
  map.resources :clubs
  map.resources :users, :path_prefix => '/:club'
  map.resources :posts, :path_prefix => '/:club'

I don't see how rails knows what :club is. Do I have to set it
somewhere (in my application controller)?

Concrete I have the following problem:
But when I use <%= link_to "new post", post_url(1) %>
I get an error post_url failed to generate from
{:club=>"1", :controller=>"posts", :action=>"show"}, expected:
{:controller=>"posts", :action=>"show"}, diff: {:club=>"1"}

It seems that :club = 1 when it actualy should be a string (zero)

Many thanks in advance

When you nest resources, the route helpers that are created for that
resource will expect additional arguments to match the named
parameters provided in the :path_prefix option. So, for example, the
route helper for ClubsController#new would just be new_club_path, but
the route helper for PostsController#new would be new_club_path(:club
=> X) or just new_club_path(X), where X is the parent Club or the
parent Club's ID.

In your example, it looks like you might be using the wrong helper.
Your link_to label is "new post" but the route helper you are using is
for PostsController#show. What you probably want is this: <%= link_to
"new post", new_post_path(1) %>. (The show helper [post_path] will
require two arguments: the parent Club and the existing Post to be
shown. It would be called as post_path(:club => X, :id => Y) or just
post_path(X, Y).)

Note that this just covers how the Club ID gets into the URL and
params[:club]. If you want to work with the actual club from within
any of the actions in UsersController or PostsController, those
actions will need to use params[:club] to look up the actual Club
instance, e.g., Club.find(params[:club]).