How to get DataMapper resource serial and key attributes in Ruby?

I`m trying to figure out how to get serial and key attributes set for Resource object. Basic method DataMapper::Resource.attributes returns a collection of properties, but it does not say anything about types. Of course i can check it via system call: obj.class, but cant understand how to get type information from resource instance.

Example:

class Foo
  include DataMapper::Resource

  property :id, Serial
  property :title, String, :required => true
  property :created_at, Time, :required => true
  property :flagged, Boolean, :defaul开发者_JAVA百科t => false
end

So, is there any way to get this information about internal types for resource?

Not long time ago, i figured it out by myself. All model fields are basically instances of DataMapper::Property

So, all you need is to call ModelName.properties and get options like :index, :key, etc.

Description: http://yardoc.org/docs/datamapper-dm-core/DataMapper/Property