Basics of scope_by_attribute plugin

gistfile1.rb

module ScopeByAttribute
  def self.included(base)
    base.send(:extend, ScopeByAttribute::ClassMethods)
  end

  module ClassMethods
    def scope_by_attribute(attribute)
      @scoped_attributes ||= []
      @scoped_attributes << attribute.to_sym
    end

    def method_missing(method, *args, &block)
      obj = nil
      if @scoped_attributes.present?
        @scoped_attributes.each do |attribute|
          obj = self.first(:conditions => {attribute => method.to_s})
          break if obj
        end
      end
      obj || super(method, args, &block)
    end
  end
end