Thinking Sphinx - RuntimeError: Missing Attribute for Foreign Key ...

Question

Trying to get along with Sphinx/Thinking Sphinx for the first time.

I've got my models defined as follows (simplified):

class Branch < ActiveRecord::Base
  has_many  :salesmen, :class_name => "User"
  has_many :leads, :through => :salesmen
end

class User < ActiveRecord::Base
  belongs_to :branch
  has_many :leads, :foreign_key => "owner_id"
end

class Lead < ActiveRecord::Base
  belongs_to :owner, :class_name => "User"

  define_index do
    indexes company_name    
    indexes :name, :sortable => true
    has owner.branch_id, :as => :branch_id
    indexes [owner.last_name, owner.first_name], :as => :owner_full_name, :sortable => true 
  end

end

Anytime I call

Branch.first.leads.search

I get

RuntimeError: Missing Attribute for Foreign Key branch_id

What am I doing wrong?

Answer 1

I believe you're missing a :through option on your branch relation. Try updating to:

class Lead < ActiveRecord::Base
  has_one :branch, :through => :owner

Answer 2

The issue is that Thinking Sphinx needs branch_id as an attribute in your index, so it can restrict results to just the relevant branch (because you're searching within an association).

It's not clear from your associations (or maybe that just my dire need for sleep) whether a lead belongs to a branch via the owner, or directly as well. If the former, Ben's suggestion is probably correct. Otherwise, try adding the following to your define_index block:

has branch_id, :as => :direct_branch_id

An alternative approach, after reading the comments, is to add your own search method to the leads association in Branch. A vague attempt (you will need to debug, I'm sure):

has_many :leads, :through => :salesmen do
  def search(*args)
    options = args.extract_options!
    options[:with] ||= {}
    options[:with][:branch_id] = proxy_owner.id
    args << options
    Lead.search(*args)
  end
end

This should get around the fact that you do not have a direct reference to the branch from Lead. The only possible issue is that I'm not sure whether custom extensions get loaded before or after what Thinking Sphinx injects. Give it a shot, see if it helps.

Answer 3

If you say a Lead belongs_to a Branch, then you must have a branch_id in the leads table. Since you don't, it's not a belongs_to relationship. I think you need something like this:

class Branch < ActiveRecord::Base
  has_many :leads, :through => :salesmen
  has_many :salesmen, :class_name => "User" 
end

class User < ActiveRecord::Base
  belongs_to :branch # users table has branch_id
  has_many :leads, :foreign_key => "owner_id"
end

class Lead < ActiveRecord::Base
  belongs_to :owner, :class_name => "User" # leads table has owner_id

  define_index do
    indexes :company_name    
    indexes :name, :sortable => true
    has owner.branch_id, :as => :branch_id
    indexes [owner.last_name, owner.first_name], :as => :owner_full_name, :sortable => true 
  end

end