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Rails: Hack belongs_to to allow :select

Posted by kevin Tue, 17 Apr 2007 22:57:35 GMT

For some reason most rails associations allow :select as a parameter to limit which rows are loaded, but belongs_to doesn't.

Here's my (only rudimentarily tested) monkey-patch to add it:

module ActiveRecord::Associations::ClassMethods
  def create_belongs_to_reflection(association_id, options)
    $stderr.puts "MAKING REFLECTION"
    options.assert_valid_keys(
      :select, #added
      :class_name, :foreign_key, :foreign_type, :remote, :conditions, :order, :include, :dependent, 
      :counter_cache, :extend, :polymorphic
    )
    
    reflection = create_reflection(:belongs_to, association_id, options, self)

    if options[:polymorphic]
      reflection.options[:foreign_type] ||= reflection.class_name.underscore + "_type"
    end

    reflection
  end
end
module ActiveRecord
  module Associations
    class BelongsToAssociation  @reflection.options[:select] || '*', #added
          :conditions => conditions,
          :include    => @reflection.options[:include]
        )
      end
    end
  end
end

Technorati Tags: monkey patching, ruby on rails