Support for running a _query with an http method

This allows operations like delete by query.
Included test for delete by query.

goes.go

@@ -196,6 +196,23 @@ func (c *Connection) Search(query map[string]interface{}, indexList []string, ty
 	return r.Run()
 }
 
+//Query runs a query against an index using the provided http method.
+//This method can be used to execute a delete by query, just pass in "DELETE"
+//for the HTTP method.
+func (c *Connection) Query(query map[string]interface{}, indexList []string, typeList []string, httpMethod string, extraArgs url.Values) (Response, error) {
+	r := Request{
+		Conn:      c,
+		Query:     query,
+		IndexList: indexList,
+		TypeList:  typeList,
+		method:    httpMethod,
+		api:       "_query",
+		ExtraArgs: extraArgs,
+	}
+
+	return r.Run()
+}
+
 // Scan starts scroll over an index
 func (c *Connection) Scan(query map[string]interface{}, indexList []string, typeList []string, timeout string, size int) (Response, error) {
 	v := url.Values{}

goes_test.go

@@ -508,6 +508,70 @@ func (s *GoesTestSuite) TestDelete(c *C) {
 	c.Assert(response, DeepEquals, expectedResponse)
 }
 
+func (s *GoesTestSuite) TestDeleteByQuery(c *C) {
+	indexName := "testdeletebyquery"
+	docType := "tweet"
+	docId := "1234"
+
+	conn := NewConnection(ES_HOST, ES_PORT)
+	// just in case
+	conn.DeleteIndex(indexName)
+
+	_, err := conn.CreateIndex(indexName, map[string]interface{}{})
+	c.Assert(err, IsNil)
+	defer conn.DeleteIndex(indexName)
+
+	d := Document{
+		Index: indexName,
+		Type:  docType,
+		Id:    docId,
+		Fields: map[string]interface{}{
+			"user": "foo",
+		},
+	}
+
+	_, err = conn.Index(d, url.Values{})
+	c.Assert(err, IsNil)
+
+	_, err = conn.RefreshIndex(indexName)
+	c.Assert(err, IsNil)
+
+	query := map[string]interface{}{
+		"query": map[string]interface{}{
+			"bool": map[string]interface{}{
+				"must": []map[string]interface{}{
+					{
+						"match_all": map[string]interface{}{},
+					},
+				},
+			},
+		},
+	}
+
+	//should be 1 doc before delete by query
+	response, err := conn.Search(query, []string{indexName}, []string{docType}, url.Values{})
+	c.Assert(err, IsNil)
+	c.Assert(response.Hits.Total, Equals, uint64(1))
+
+	response, err = conn.Query(query, []string{indexName}, []string{docType}, "DELETE", url.Values{})
+
+	c.Assert(err, IsNil)
+
+	expectedResponse := Response{
+		Found:   false,
+		Index:   "",
+		Type:    "",
+		Id:      "",
+		Version: 0,
+	}
+	c.Assert(response, DeepEquals, expectedResponse)
+
+	//should be 0 docs after delete by query
+	response, err = conn.Search(query, []string{indexName}, []string{docType}, url.Values{})
+	c.Assert(err, IsNil)
+	c.Assert(response.Hits.Total, Equals, uint64(0))
+}
+
 func (s *GoesTestSuite) TestGet(c *C) {
 	indexName := "testget"
 	docType := "tweet"