Set / Override OpenTelemetry Subscriber settings based on Python Version

google/cloud/pubsub_v1/subscriber/client.py

@@ -14,6 +14,7 @@
 
 from __future__ import absolute_import
 
+import sys
 import os
 import typing
 from typing import cast, Any, Callable, Optional, Sequence, Union
@@ -93,6 +94,23 @@ def __init__(
 
         self.subscriber_options = types.SubscriberOptions(*subscriber_options)
 
+        # Set / override Open Telemetry  option.
+        self._open_telemetry_enabled = (
+            self.subscriber_options.enable_open_telemetry_tracing
+        )
+        # OpenTelemetry features used by the library are not supported in Python versions <= 3.7.
+        # Refer https://github.com/open-telemetry/opentelemetry-python/issues/3993#issuecomment-2211976389
+        if (
+            self.subscriber_options.enable_open_telemetry_tracing
+            and sys.version_info.major == 3
+            and sys.version_info.minor < 8
+        ):
+            warnings.warn(
+                message="Open Telemetry for Python version 3.7 or lower is not supported. Disabling Open Telemetry tracing.",
+                category=RuntimeWarning,
+            )
+            self._open_telemetry_enabled = False
+
     @classmethod
     def from_service_account_file(  # type: ignore[override]
         cls, filename: str, **kwargs: Any

tests/unit/pubsub_v1/subscriber/test_subscriber_client.py

@@ -320,19 +320,24 @@ async def test_sync_pull_warning_if_return_immediately_async(creds):
 
 
 @pytest.mark.parametrize(
-    "enable_open_telemetry_tracing",
+    "enable_open_telemetry",
     [
         True,
         False,
     ],
 )
-def test_subscriber_settings(creds, enable_open_telemetry_tracing):
+def test_opentelemetry_subscriber_setting(creds, enable_open_telemetry):
     options = types.SubscriberOptions(
-        enable_open_telemetry_tracing=enable_open_telemetry_tracing
-    )
-    client = subscriber.Client(subscriber_options=options, credentials=creds)
-
-    assert (
-        client.subscriber_options.enable_open_telemetry_tracing
-        == enable_open_telemetry_tracing
+        enable_open_telemetry_tracing=enable_open_telemetry,
     )
+    if sys.version_info >= (3, 8) or enable_open_telemetry is False:
+        client = subscriber.Client(credentials=creds, subscriber_options=options)
+        assert client.subscriber_options == options
+        assert client._open_telemetry_enabled == enable_open_telemetry
+    else:
+        with pytest.warns(
+            RuntimeWarning,
+            match="Open Telemetry for Python version 3.7 or lower is not supported. Disabling Open Telemetry tracing.",
+        ):
+            client = subscriber.Client(credentials=creds, subscriber_options=options)
+            assert client._open_telemetry_enabled is False