feat: return singleton success future for exactly-once methods in Message (#608)

pradn · web-flow · commit 253ced28f308 · 2022-03-09T13:48:08.000-05:00
* Return singleton success future for exactly-once methods in subscriber.Message
diff --git a/google/cloud/pubsub_v1/subscriber/message.py b/google/cloud/pubsub_v1/subscriber/message.py
@@ -40,6 +40,9 @@
   attributes: {}
 }}"""
 
+_SUCCESS_FUTURE = futures.Future()
+_SUCCESS_FUTURE.set_result(AcknowledgeStatus.SUCCESS)
+
 
 def _indent(lines: str, prefix: str = "  ") -> str:
     """Indent some text.
@@ -291,12 +294,13 @@ def ack_with_response(self) -> "futures.Future":
             pubsub_v1.subscriber.exceptions.AcknowledgeError exception
             will be thrown.
         """
-        future = futures.Future()
-        req_future = None
+        req_future: Optional[futures.Future]
         if self._exactly_once_delivery_enabled_func():
+            future = futures.Future()
             req_future = future
         else:
-            future.set_result(AcknowledgeStatus.SUCCESS)
+            future = _SUCCESS_FUTURE
+            req_future = None
         time_to_ack = math.ceil(time.time() - self._received_timestamp)
         self._request_queue.put(
             requests.AckRequest(
@@ -390,12 +394,13 @@ def modify_ack_deadline_with_response(self, seconds: int) -> "futures.Future":
             will be thrown.
 
         """
-        future = futures.Future()
-        req_future = None
+        req_future: Optional[futures.Future]
         if self._exactly_once_delivery_enabled_func():
+            future = futures.Future()
             req_future = future
         else:
-            future.set_result(AcknowledgeStatus.SUCCESS)
+            future = _SUCCESS_FUTURE
+            req_future = None
 
         self._request_queue.put(
             requests.ModAckRequest(
@@ -451,12 +456,13 @@ def nack_with_response(self) -> "futures.Future":
             will be thrown.
 
         """
-        future = futures.Future()
-        req_future = None
+        req_future: Optional[futures.Future]
         if self._exactly_once_delivery_enabled_func():
+            future = futures.Future()
             req_future = future
         else:
-            future.set_result(AcknowledgeStatus.SUCCESS)
+            future = _SUCCESS_FUTURE
+            req_future = None
 
         self._request_queue.put(
             requests.NackRequest(
diff --git a/tests/unit/pubsub_v1/subscriber/test_message.py b/tests/unit/pubsub_v1/subscriber/test_message.py
@@ -156,6 +156,7 @@ def test_ack_with_response_exactly_once_delivery_disabled():
             )
         )
         assert future.result() == AcknowledgeStatus.SUCCESS
+        assert future == message._SUCCESS_FUTURE
         check_call_types(put, requests.AckRequest)
 
 
@@ -205,6 +206,7 @@ def test_modify_ack_deadline_with_response_exactly_once_delivery_disabled():
             requests.ModAckRequest(ack_id="bogus_ack_id", seconds=60, future=None)
         )
         assert future.result() == AcknowledgeStatus.SUCCESS
+        assert future == message._SUCCESS_FUTURE
         check_call_types(put, requests.ModAckRequest)
 
 
@@ -242,6 +244,7 @@ def test_nack_with_response_exactly_once_delivery_disabled():
             )
         )
         assert future.result() == AcknowledgeStatus.SUCCESS
+        assert future == message._SUCCESS_FUTURE
         check_call_types(put, requests.NackRequest)
 
 

Original file line number	Diff line number	Diff line change
`@@ -156,6 +156,7 @@ def test_ack_with_response_exactly_once_delivery_disabled():`
`156`	`156`	`)`
`157`	`157`	`)`
`158`	`158`	`assert future.result() == AcknowledgeStatus.SUCCESS`
	`159`	`+ assert future == message._SUCCESS_FUTURE`
`159`	`160`	`check_call_types(put, requests.AckRequest)`
`160`	`161`
`161`	`162`
`@@ -205,6 +206,7 @@ def test_modify_ack_deadline_with_response_exactly_once_delivery_disabled():`
`205`	`206`	`requests.ModAckRequest(ack_id="bogus_ack_id", seconds=60, future=None)`
`206`	`207`	`)`
`207`	`208`	`assert future.result() == AcknowledgeStatus.SUCCESS`
	`209`	`+ assert future == message._SUCCESS_FUTURE`
`208`	`210`	`check_call_types(put, requests.ModAckRequest)`
`209`	`211`
`210`	`212`
`@@ -242,6 +244,7 @@ def test_nack_with_response_exactly_once_delivery_disabled():`
`242`	`244`	`)`
`243`	`245`	`)`
`244`	`246`	`assert future.result() == AcknowledgeStatus.SUCCESS`
	`247`	`+ assert future == message._SUCCESS_FUTURE`
`245`	`248`	`check_call_types(put, requests.NackRequest)`
`246`	`249`
`247`	`250`