aaa_test_model.rb

require 'rubygems'
require 'dm-core'
require 'pathname'
require Pathname(__FILE__).dirname + 'lib/ssbe_adapter'

DataMapper.setup(:default, :adapter => :ssbe, :service_descriptor_uri => 'http://core.ssbe.localhost/service_descriptors')

class Client
  include DataMapper::Resource
  set_service_type  "http://systemshepherd.com/services/kernel"
  set_resource_name "AllClients"
  set_mimetype      "application/vnd.absolute-performance.sysshep+json"

  property :name,   String

end

clients = Client.all

puts clients.inspect
# => [#<Client name="TestClient" href="http://core.ssbe.localhost/clients/TestClient">]

ssbe_adapter.rb

require 'rubygems'
require 'resourceful'
require 'json'
gem 'dm-core', '>=0.9.3'

module DataMapper
  module Adapters
    class SsbeAdapter < AbstractAdapter

      def initialize(name, uri_or_options)
        super

        @service_descriptor_uri = uri_or_options[:service_descriptor_uri]
        @http = Resourceful::HttpAccessor.new(:cache_manager => Resourceful::InMemoryCacheManager.new,
                                              :logger => Resourceful::StdOutLogger.new)
        @http.auth_manager.add_auth_handler Resourceful::SSBEAuthenticator.new('dev', 'dev')
        @service_descriptor = @http.resource(@service_descriptor_uri).get.body
        @service_descriptor = JSON.parse(@service_descriptor)
      end

      def read_many(query)
        service_type = query.model.service_type
        resource_name = query.model.resource_name
        mimetype = query.model.mimetype

        resource_descriptor_uri = @service_descriptor["items"].find { |i| i["service_type"] == service_type }["href"]
        resource_descriptor = JSON.parse(@http.resource(resource_descriptor_uri).get.body)

        resource_uri = resource_descriptor["resources"].find { |i| i["name"] == resource_name }["href"]

        doc = JSON.parse(@http.resource(resource_uri).get(:accept => mimetype).body)

        Collection.new(query) do |collection|
          doc['items'].each do |item|
            collection.load(
              query.fields.map { |prop| item[prop.field.to_s] }
            )
          end
        end     
      end

    end

  end

  module Model
    attr_reader :service_type, :resource_name, :mimetype

    def set_service_type(uri)
      @service_type = uri
    end

    def set_resource_name(name)
      @resource_name = name
    end

    def set_mimetype(mimetype)
      @mimetype = mimetype
    end

  end
  
end