Manipulate HABTM relationships in views

Hi everyone.
I’m currently working on a bodybuilding supplement Website which have 3
models :

  • Stack :
    has_and_belongs_to_many :products
  • Product :
    has_and_belongs_to_many :stacks
    has_and_belongs_to_many :ingredients
  • Ingredient :
    has_and_belongs_to_many :products

Now what I am trying to do is list all the ingredients for a Stack
(using standard params[:id]). It seems that I cannot pass multiple
product_ids (but one id work fine!) to get the ingredients listing.

Here’s a partial code from my controller :

=== START ===

def stack
begin
@stack = Stack.find(params[:id])
render :template => “public/stack_#{@lang}”
rescue ActiveRecord::RecordNotFound
logger.error(“Attempt to access invalid stack #{params[:id]}”)
flash[:notice] = “Désolé, cette formule est introuvable.”
redirect_to :action => :index
end
end

=== END ===

Any help would be appreciate and I can provide more information if my
request isn’t clear enought.

I am using RAILS_GEM_VERSION = ‘1.2.6’

Thanks

Hugues