add heartbeat interval

Signed-off-by: Ben Cassell <ben.cassell@databricks.com>

src/databricks/sql/thrift_backend.py

@@ -55,6 +55,7 @@
 
 TIMESTAMP_AS_STRING_CONFIG = "spark.thriftserver.arrowBasedRowSet.timestampAsString"
 DEFAULT_SOCKET_TIMEOUT = float(900)
+DEFAULT_STATEMENT_HEARTBEAT_INTERVAL = float(25)
 
 # see Connection.__init__ for parameter descriptions.
 # - Min/Max avoids unsustainable configs (sane values are far more constrained)
@@ -77,6 +78,7 @@ class ThriftBackend:
     _retry_stop_after_attempts_count: int
     _retry_stop_after_attempts_duration: float
     _retry_delay_default: float
+    _statement_heartbeat_interval: float
 
     def __init__(
         self,
@@ -134,6 +136,10 @@ def __init__(
         #  An integer representing the maximum number of redirects to follow for a request.
         #  This number must be <= _retry_stop_after_attempts_count.
         #  (defaults to None)
+        # _statement_heartbeat_interval
+        # The number of seconds to wait between sending GetOperationStatus requests to the server.
+        # (defaults to 25), as the server will already wait 5 seconds before responding to the request if the
+        # statement is still running, making a 30 second total interval between each heartbeat.
         # max_download_threads
         #  Number of threads for handling cloud fetch downloads. Defaults to 10
 
@@ -231,6 +237,10 @@ def __init__(
         # setTimeout defaults to 15 minutes and is expected in ms
         self._transport.setTimeout(timeout and (float(timeout) * 1000.0))
 
+        self._statement_heartbeat_interval = kwargs.get(
+            "_statement_heartbeat_interval", DEFAULT_STATEMENT_HEARTBEAT_INTERVAL
+        )
+
         self._transport.setCustomHeaders(dict(http_headers))
         protocol = thrift.protocol.TBinaryProtocol.TBinaryProtocol(self._transport)
         self._client = TCLIService.Client(protocol)
@@ -802,6 +812,7 @@ def _wait_until_command_done(self, op_handle, initial_operation_status_resp):
             ttypes.TOperationState.RUNNING_STATE,
             ttypes.TOperationState.PENDING_STATE,
         ]:
+            time.sleep(self._statement_heartbeat_interval)
             poll_resp = self._poll_for_status(op_handle)
             operation_state = poll_resp.operationState
             self._check_command_not_in_error_or_closed_state(op_handle, poll_resp)