has_many :through 2 models

rubyonrails-talk
1

Let's say I have the following models:

User has_many :orders has_many :items, :through => :orders

Order belongs_to :user has_many :items has_many :products, :through => :items

Item belongs_to :order belongs_to :product

Product has_many :items has_many :orders, :through => items

Is it possible to do: @user = User.find(1) @products = @user.products

I have tried but it ddin't work. If it is impossible to do, what would be the solution to that?

2

If all you need to do is get a list of all products ordered by a given user, you could write the following method

class User << ActiveRecord::Base

def products   Product.find :all, :include => [:items], :conditions => ["items.user_id = ? and products.id = items.product_id", self.id] end

end

Best,

kb

3

Therefore this means that :through can only work through one model.

Thank you Kyle for your tip.

4

Try this:

http://code.torchbox.com/svn/rails/plugins/nested_has_many_through/

See the README for more info.