Added the exponential backoff code

Author: jprakash-db

src/databricks/sql/auth/retry.py

@@ -285,14 +285,27 @@ def sleep_for_retry(self, response: BaseHTTPResponse) -> bool:
         """
         retry_after = self.get_retry_after(response)
         if retry_after:
-            backoff = self.get_backoff_time()
+            backoff = self.get_exponential_backoff()
             proposed_wait = max(backoff, retry_after)
             self.check_proposed_wait(proposed_wait)
             time.sleep(proposed_wait)
             return True
 
         return False
 
+    def get_exponential_backoff(self) -> float:
+        """
+        This method implements the exponential backoff algorithm to calculate the delay between retries.
+        :return:
+        """
+
+        current_attempt = self.stop_after_attempts_count - self.total
+        proposed_backoff = (2**current_attempt) * self.delay_min
+        proposed_backoff = min(proposed_backoff, self.delay_max)
+        self.check_proposed_wait(proposed_backoff)
+
+        return proposed_backoff
+
     def get_backoff_time(self) -> float:
         """Calls urllib3's built-in get_backoff_time.
 

src/databricks/sql/thrift_backend.py

@@ -64,8 +64,8 @@
 # - 900s attempts-duration lines up w ODBC/JDBC drivers (for cluster startup > 10 mins)
 _retry_policy = {  # (type, default, min, max)
     "_retry_delay_min": (float, 1, 0.1, 60),
-    "_retry_delay_max": (float, 60, 5, 3600),
-    "_retry_stop_after_attempts_count": (int, 30, 1, 60),
+    "_retry_delay_max": (float, 30, 5, 3600),
+    "_retry_stop_after_attempts_count": (int, 5, 1, 60),
     "_retry_stop_after_attempts_duration": (float, 900, 1, 86400),
     "_retry_delay_default": (float, 5, 1, 60),
 }