[MODEL] Added the update_document_attributes method

Allows to directly perform a _partial_ update of a document, without consideration
for the changed attributes (as is the case in `update_document`)

Example:

    @Article = Article.first
    @article.title = "New title"
    @article.__elasticsearch__.update_document_attributes({title: "New title"})

Closes elastic#230

Author: meesterdude

elasticsearch-model/lib/elasticsearch/model/indexing.rb

@@ -351,6 +351,29 @@ def update_document(options={})
             index_document(options)
           end
         end
+
+        # Allows for partial update of a document by manually supplying the changes
+        #
+        # @param attributes [Hash] Required attributes to be updated
+        # @param options [Hash] Optional arguments for passing to the client
+        #
+        # @example update just the title
+        #
+        #     @article = Article.first
+        #     @article.title = "New title"
+        #     @article.__elasticsearch__.update_document_attributes({title: "New title"})
+        #
+        # @return [Hash] The response from Elasticsearch
+        #
+        #
+        def update_document_attributes(attributes,options={})
+          client.update(
+            { index: index_name,
+              type:  document_type,
+              id:    self.id,
+              body:  { doc: attributes } }.merge(options)
+          )
+        end
       end
 
     end

elasticsearch-model/test/integration/active_record_basic_test.rb

@@ -128,6 +128,19 @@ class ::Article < ActiveRecord::Base
           assert_equal 1, response.records.size
         end
 
+         should "allow specific updates to be made to the document directly" do
+          article = Article.first
+
+          article.update_document_attributes({title: 'green grass'})
+
+          Article.__elasticsearch__.refresh_index!
+
+          response = Article.search 'title:green'
+
+          assert_equal 1, response.results.size
+          assert_equal 1, response.records.size
+        end
+
         should "return results for a DSL search" do
           response = Article.search query: { match: { title: { query: 'test' } } }
 

elasticsearch-model/test/unit/indexing_test.rb

@@ -323,6 +323,46 @@ def as_indexed_json(options={})
 
         instance.update_document
       end
+
+      should "have the update_document_attributes method" do
+        client   = mock('client')
+        instance = ::DummyIndexingModelWithCallbacks.new
+
+        client.expects(:update).with do |payload|
+          assert_equal 'foo',  payload[:index]
+          assert_equal 'bar',  payload[:type]
+          assert_equal '1',    payload[:id]
+        end
+
+        instance.expects(:client).returns(client)
+        instance.expects(:index_name).returns('foo')
+        instance.expects(:document_type).returns('bar')
+        instance.expects(:id).returns('1')
+
+        instance.update_document_attributes({})
+      end
+
+      should "update only the supplied attributes" do
+        client   = mock('client')
+        instance = ::DummyIndexingModelWithCallbacks.new
+
+        # Set the fake `changes` hash
+        instance.instance_variable_set(:@__changed_attributes, {foo: 'bar'})
+
+        client.expects(:update).with do |payload|
+          assert_equal 'foo',  payload[:index]
+          assert_equal 'bar',  payload[:type]
+          assert_equal '1',    payload[:id]
+          assert_equal({title: 'green'}, payload[:body][:doc])
+        end
+
+        instance.expects(:client).returns(client)
+        instance.expects(:index_name).returns('foo')
+        instance.expects(:document_type).returns('bar')
+        instance.expects(:id).returns('1')
+
+        instance.update_document_attributes({title: "green"})
+      end
     end
 
     context "Re-creating the index" do