gistfile1.rb

class CheckAssociationProcessor < ETL::Processor::RowProcessor
  attr_reader :ids, :foreign_key
  
  def initialize(control, configuration)
    super
    @foriegn_key = configuration[:foreign_key] || raise ArgumentError, ":foreign_key option required"
    model = configuration[:model] || raise ArgumentError, ":model option required"
    
    # Optional :conditions or :find_options
    find_options = cond = (configuration[:conditions] ? {:conditions => cond} : configuration[:find_options]) || {}
    @ids = model.find(:all, {:select => "id"}.merge(find_options)).map {|m| m.id}
  end
  
  def process(row)
    self.ids.include?(row[foreign_key.to_sym].to_i) ? row : []
  end
end



before_write CheckAssociationProcessor, :model => EnterprisePricing::Route, :foreign_key => "route_id"