[MODEL] Added a convenience accessor for the aggregations part of response

Closes elastic#376

Author: delwaterman

elasticsearch-model/lib/elasticsearch/model/response.rb

@@ -65,6 +65,12 @@ def timed_out
         def shards
           Hashie::Mash.new(response['_shards'])
         end
+
+        # Returns a Hashie::Mash of the aggregations
+        #
+        def aggregations
+          response['aggregations'] ? Hashie::Mash.new(response['aggregations']) : nil
+        end
       end
     end
   end

elasticsearch-model/test/unit/response_test.rb

@@ -7,7 +7,8 @@ def self.index_name;    'foo'; end
       def self.document_type; 'bar'; end
     end
 
-    RESPONSE = { 'took' => '5', 'timed_out' => false, '_shards' => {'one' => 'OK'}, 'hits' => { 'hits' => [] } }
+    RESPONSE = { 'took' => '5', 'timed_out' => false, '_shards' => {'one' => 'OK'}, 'hits' => { 'hits' => [] },
+                 'aggregations' => {'foo' => {'bar' => 10}}}
 
     setup do
       @search  = Elasticsearch::Model::Searching::SearchRequest.new OriginClass, '*'
@@ -63,5 +64,14 @@ def self.document_type; 'bar'; end
 
       Elasticsearch::Model::Response::Response.new OriginClass, @search
     end
+
+    should "access the aggregations" do
+      @search.expects(:execute!).returns(RESPONSE)
+
+      response = Elasticsearch::Model::Response::Response.new OriginClass, @search
+      assert_respond_to response, :aggregations
+      assert_kind_of Hashie::Mash, response.aggregations.foo
+      assert_equal 10, response.aggregations.foo.bar
+    end
   end
 end