[STORE] Implemented the gateway pattern for the repository integration

To provide flexibility to the end-user, the integration of the "Repository" module
has been refactored to proxy all repository methods via a gateway.

This allows users to set up the repository in a custom class, with class methods, in a DSL-like fashion:

    class NoteRepository
      include Elasticsearch::Persistence::Repository

      klass Note
      index :my_notes

      mapping do
        indexes :title, analyzer: 'snowball'
      end

      client.transport.logger = Logger.new(STDERR)

      gateway do
        def serialize(document)
          super.merge(special: 'stuff')
        end
      end
    end

The bundled Repository class can be configured via a block passed to the initializer:

    repository = Elasticsearch::Persistence::Repository.new do
      klass Note
      index :my_notes

      mapping do
        indexes :title, analyzer: 'snowball'
      end

      client.transport.logger = Logger.new(STDERR)
    end

The repository methods can be accessed via the class or instance methods:

    NoteRepository.klass Note
    repository.klass Note

Author: karmi

elasticsearch-persistence/lib/elasticsearch/persistence.rb

@@ -13,9 +13,8 @@
 require 'elasticsearch/persistence/repository/store'
 require 'elasticsearch/persistence/repository/find'
 require 'elasticsearch/persistence/repository/search'
-require 'elasticsearch/persistence/repository'
-
 require 'elasticsearch/persistence/repository/class'
+require 'elasticsearch/persistence/repository'
 
 module Elasticsearch
   module Persistence

elasticsearch-persistence/lib/elasticsearch/persistence/repository.rb

@@ -1,15 +1,37 @@
 module Elasticsearch
   module Persistence
+    module GatewayDelegation
+      def method_missing(method_name, *arguments, &block)
+        gateway.respond_to?(method_name) ? gateway.__send__(method_name, *arguments, &block) : super
+      end
+
+      def respond_to?(method_name, include_private=false)
+        gateway.respond_to?(method_name) || super
+      end
+    end
 
     module Repository
-      include Elasticsearch::Persistence::Client
-      include Elasticsearch::Persistence::Repository::Naming
-      include Elasticsearch::Persistence::Repository::Serialize
-      include Elasticsearch::Persistence::Repository::Store
-      include Elasticsearch::Persistence::Repository::Find
-      include Elasticsearch::Persistence::Repository::Search
+      def self.included(base)
+        gateway = Elasticsearch::Persistence::Repository::Class.new
+
+        base.class_eval do
+          define_method :gateway do
+            @gateway ||= gateway
+          end
+
+          include GatewayDelegation
+        end
+
+        (class << base; self; end).class_eval do
+          define_method :gateway do |&block|
+            @gateway ||= gateway
+            @gateway.instance_eval(&block) if block
+            @gateway
+          end
 
-      include Elasticsearch::Model::Indexing::ClassMethods
+          include GatewayDelegation
+        end
+      end
 
       def new(options={}, &block)
         Elasticsearch::Persistence::Repository::Class.new options, &block

elasticsearch-persistence/lib/elasticsearch/persistence/repository/class.rb

@@ -3,7 +3,14 @@ module Persistence
     module Repository
 
       class Class
-        include Elasticsearch::Persistence::Repository
+        include Elasticsearch::Persistence::Client
+        include Elasticsearch::Persistence::Repository::Naming
+        include Elasticsearch::Persistence::Repository::Serialize
+        include Elasticsearch::Persistence::Repository::Store
+        include Elasticsearch::Persistence::Repository::Find
+        include Elasticsearch::Persistence::Repository::Search
+
+        include Elasticsearch::Model::Indexing::ClassMethods
 
         attr_reader :options
 

elasticsearch-persistence/test/unit/repository_class_test.rb

@@ -3,29 +3,43 @@
 class Elasticsearch::Persistence::RepositoryClassTest < Test::Unit::TestCase
   context "The default repository class" do
 
-    should "be created from the module" do
-      repository = Elasticsearch::Persistence::Repository.new
-      assert_instance_of Elasticsearch::Persistence::Repository::Class, repository
-    end
+    context "when initialized" do
+      should "be created from the module" do
+        repository = Elasticsearch::Persistence::Repository.new
+        assert_instance_of Elasticsearch::Persistence::Repository::Class, repository
+      end
 
-    should "store and access the options" do
-      repository = Elasticsearch::Persistence::Repository::Class.new foo: 'bar'
-      assert_equal 'bar', repository.options[:foo]
-    end
+      should "store and access the options" do
+        repository = Elasticsearch::Persistence::Repository::Class.new foo: 'bar'
+        assert_equal 'bar', repository.options[:foo]
+      end
 
-    should "instance eval a passed block" do
-      $foo = 100
-      repository = Elasticsearch::Persistence::Repository::Class.new() { $foo += 1 }
-      assert_equal 101, $foo
+      should "instance eval a passed block" do
+        $foo = 100
+        repository = Elasticsearch::Persistence::Repository::Class.new() { $foo += 1 }
+        assert_equal 101, $foo
+      end
+
+      should "call a passed block with self" do
+        foo = 100
+        repository = Elasticsearch::Persistence::Repository::Class.new do |r|
+          assert_instance_of Elasticsearch::Persistence::Repository::Class, r
+          foo += 1
+        end
+        assert_equal 101, foo
+      end
     end
 
-    should "call a passed block with self" do
-      foo = 100
-      repository = Elasticsearch::Persistence::Repository::Class.new do |r|
-        assert_instance_of Elasticsearch::Persistence::Repository::Class, r
-        foo += 1
+    should "include the repository methods" do
+      repository = Elasticsearch::Persistence::Repository::Class.new
+
+      %w( index_name  document_type  klass
+          mappings  settings  client  client=
+          create_index!  delete_index!  refresh_index!
+          save  delete  serialize  deserialize
+          exists?  find  search ).each do |method|
+        assert_respond_to repository, method
       end
-      assert_equal 101, foo
     end
 
   end

elasticsearch-persistence/test/unit/repository_module_test.rb

@@ -2,5 +2,111 @@
 
 class Elasticsearch::Persistence::RepositoryModuleTest < Test::Unit::TestCase
   context "The repository module" do
+
+    class DummyModel
+      def initialize(attributes={})
+        @attributes = attributes
+      end
+
+      def to_hash
+        @attributes
+      end
+
+      def inspect
+        "<Note #{@attributes.inspect}>"
+      end
+    end
+
+    setup do
+      class DummyRepository
+        include Elasticsearch::Persistence::Repository
+      end
+    end
+
+    teardown do
+      Elasticsearch::Persistence::RepositoryModuleTest.__send__ :remove_const, :DummyRepository
+    end
+
+    context "when included" do
+      should "set up the gateway for the class and instance" do
+        assert_respond_to DummyRepository,     :gateway
+        assert_respond_to DummyRepository.new, :gateway
+
+        assert_instance_of Elasticsearch::Persistence::Repository::Class, DummyRepository.gateway
+        assert_instance_of Elasticsearch::Persistence::Repository::Class, DummyRepository.new.gateway
+      end
+
+      should "proxy repository methods from the class to the gateway" do
+        class DummyRepository
+          include Elasticsearch::Persistence::Repository
+
+          index :foobar
+          klass DummyModel
+          type  :my_dummy_model
+          mapping { indexes :title, analyzer: 'snowball' }
+        end
+
+        repository = DummyRepository.new
+
+        assert_equal :foobar,         DummyRepository.index
+        assert_equal DummyModel,      DummyRepository.klass
+        assert_equal :my_dummy_model, DummyRepository.type
+        assert_equal 'snowball', DummyRepository.mappings.to_hash[:my_dummy_model][:properties][:title][:analyzer]
+
+        assert_equal :foobar,         repository.index
+        assert_equal DummyModel,      repository.klass
+        assert_equal :my_dummy_model, repository.type
+        assert_equal 'snowball', repository.mappings.to_hash[:my_dummy_model][:properties][:title][:analyzer]
+      end
+
+      should "proxy repository methods from the instance to the gateway" do
+        class DummyRepository
+          include Elasticsearch::Persistence::Repository
+        end
+
+        repository = DummyRepository.new
+        repository.index :foobar
+        repository.klass DummyModel
+        repository.type  :my_dummy_model
+        repository.mapping { indexes :title, analyzer: 'snowball' }
+
+        assert_equal :foobar,         DummyRepository.index
+        assert_equal DummyModel,      DummyRepository.klass
+        assert_equal :my_dummy_model, DummyRepository.type
+        assert_equal 'snowball', DummyRepository.mappings.to_hash[:my_dummy_model][:properties][:title][:analyzer]
+
+        assert_equal :foobar,         repository.index
+        assert_equal DummyModel,      repository.klass
+        assert_equal :my_dummy_model, repository.type
+        assert_equal 'snowball', repository.mappings.to_hash[:my_dummy_model][:properties][:title][:analyzer]
+      end
+
+      should "allow to define gateway methods in the class definition" do
+        class DummyRepository
+          include Elasticsearch::Persistence::Repository
+
+          gateway do
+            def serialize(document)
+              'FAKE!'
+            end
+          end
+        end
+
+        repository = DummyRepository.new
+        repository.client.transport.logger = Logger.new(STDERR)
+
+        client = mock
+        client.expects(:index).with do |arguments|
+          assert_equal('xxx',   arguments[:id])
+          assert_equal('FAKE!', arguments[:body])
+        end
+        repository.gateway.expects(:client).returns(client)
+
+        repository.gateway.expects(:__get_id_from_document).returns('xxx')
+
+        repository.save( id: '123', foo: 'bar' )
+      end
+    end
+
   end
 end