add wait on delay (elastic#794)

Author: fxdgear

elasticsearch/transport.py

@@ -294,7 +294,7 @@ def perform_request(self, method, url, headers=None, params=None, body=None):
 
  if body is not None:
  try:
- body = body.encode('utf-8', 'surrogatepass') 
+ body = body.encode('utf-8', 'surrogatepass')
  except (UnicodeDecodeError, AttributeError):
  # bytes/str - no need to re-encode
  pass
@@ -311,6 +311,10 @@ def perform_request(self, method, url, headers=None, params=None, body=None):
  connection = self.get_connection()
 
  try:
+ # add a delay before attempting the next retry
+ # 0, 1, 3, 7, etc...
+ delay = 2**attempt - 1
+ time.sleep(delay)
  status, headers_response, data = connection.perform_request(method, url, params, body, headers=headers, ignore=ignore, timeout=timeout)
 
  except TransportError as e: