Delete mapping is no longer supported in 2.x+ versions of ES

goes.go

@@ -504,6 +504,11 @@ func (c *Client) Update(d Document, query interface{}, extraArgs url.Values) (*R
 
 // DeleteMapping deletes a mapping along with all data in the type
 func (c *Client) DeleteMapping(typeName string, indexes []string) (*Response, error) {
+	if version, err := c.Version(); err != nil {
+		return nil, err
+	} else if version > "2" {
+		return nil, errors.New("Deletion of mappings is not supported in ES 2.x and above.")
+	}
 
 	r := Request{
 		IndexList: indexes,

goes_test.go

@@ -1365,6 +1365,10 @@ func (s *GoesTestSuite) TestDeleteMapping(c *C) {
 	time.Sleep(200 * time.Millisecond)
 
 	response, err = conn.DeleteMapping("tweet", []string{indexName})
+	if version, _ := conn.Version(); version > "2" {
+		c.Assert(err, ErrorMatches, ".*not supported.*")
+		return
+	}
 	c.Assert(err, IsNil)
 
 	c.Assert(response.Acknowledged, Equals, true)