Rails 3: Multiple has_one associations & seeding

Question

I\'m working with a data concept that Rails doesn\'t seem to do great with - a Route has two (and only two) Airports. I finally figured out how to hard-code my foreign keys so t

Answer 1

I would change your model to specify a different symbol for each relationship:

class Route < ActiveRecord::Base
  has_one :from_airport, :foreign_key => 'from_airport_id', :class_name => 'Airport'
  has_one :to_airport, :foreign_key => 'to_airport_id', :class_name => 'Airport'
end

Since enabling a has_one lets you access that relationship through the name (e.g. route.airport), these need to be different.

To get your seeding to work, call .id on the airport:

Route.create(:from_airport_id => @kpdx.id, :to_airport_id => @ksea.id, :route => "RIVR6 BTG OLM6")

Example:

ruby-1.9.2-p136 :001 > a = Airport.create(:icao => 'KPDX', :name => 'Portland International Airport')
 => #<Airport id: 1, icao: "KPDX", name: "Portland International Airport", created_at: "2011-03-01 02:44:42", updated_at: "2011-03-01 02:44:42">
ruby-1.9.2-p136 :002 > b = Airport.create(:icao => 'ABCD', :name => 'Another Airport')
 => #<Airport id: 2, icao: "ABCD", name: "Another Airport", created_at: "2011-03-01 02:46:22", updated_at: "2011-03-01 02:46:22">
ruby-1.9.2-p136 :003 > r = Route.create(:to_airport_id => a.id, :from_airport_id => b.id)
 => #<Route id: 3, from_airport_id: 2, to_airport_id: 1, route: nil, created_at: "2011-03-01 02:46:36", updated_at: "2011-03-01 02:46:36">