gistfile1.rb

module ActiveRecord
  module Searchable
    def self.included(base)
      base.extend(ClassMethods)  
    end
    
    module ClassMethods
      def searchable_on(*args)
        args.flatten!
        @args = args.compact
        
        self.instance_eval do
          def search(query)
            fields = @args.join(',')
            query = ActiveRecord::Base.connection.quote(query)
            all({
              :conditions => "MATCH (#{fields}) AGAINST (#{query} IN BOOLEAN MODE)",
              :order => 'score DESC',
              :select => "SQL_CALC_FOUND_ROWS *, MATCH (#{fields}) AGAINST (#{query}) AS score"
            })
          end
        end
      end
      
    end
  end
end

ActiveRecord::Base.class_eval { include ActiveRecord::Searchable }