retries: fix issue so max_retries can be overridden to zero via messa…

…ge options (#646)

dramatiq/middleware/retries.py

@@ -98,7 +98,7 @@ def after_process_message(self, broker, message, *, result=None, exception=None)
         message.options["traceback"] = traceback.format_exc(limit=30)
         message.options["requeue_timestamp"] = int(time.time() * 1000)
 
-        max_retries = message.options.get("max_retries") or actor.options.get("max_retries", self.max_retries)
+        max_retries = message.options.get("max_retries", actor.options.get("max_retries", self.max_retries))
         retry_when = actor.options.get("retry_when", self.retry_when)
         if retry_when is not None and not retry_when(retries, exception) or \
            retry_when is None and max_retries is not None and retries >= max_retries:

tests/middleware/test_retries.py

@@ -214,7 +214,8 @@ def do_work():
     assert timestamps[-1] - timestamps[0] < 0.2
 
 
-def test_actors_can_be_assigned_message_max_retries(stub_broker, stub_worker):
+@pytest.mark.parametrize("max_retries_message_option", (0, 4))
+def test_actors_can_be_assigned_message_max_retries(stub_broker, stub_worker, max_retries_message_option):
     # Given that I have a database
     attempts = []
 
@@ -225,14 +226,14 @@ def do_work():
         raise RuntimeError("failure")
 
     # When I send it a message with tight backoff and custom max retries
-    do_work.send_with_options(max_retries=4, min_backoff=50, max_backoff=500)
+    do_work.send_with_options(max_retries=max_retries_message_option, min_backoff=50, max_backoff=500)
 
     # And join on the queue
     stub_broker.join(do_work.queue_name)
     stub_worker.join()
 
     # Then I expect it to be retried as specified in the message options
-    assert sum(attempts) == 5
+    assert sum(attempts) == 1 + max_retries_message_option
 
 
 def test_actors_can_conditionally_retry(stub_broker, stub_worker):