fix(bigtable): Log warning on background task failure instead of exception

packages/google-cloud-bigtable/google/cloud/bigtable/data/_async/client.py

@@ -416,11 +416,18 @@ def _start_background_channel_refresh(self) -> None:
         ):
             # raise error if not in an event loop in async client
             CrossSync.verify_async_event_loop()
-            self._channel_refresh_task = CrossSync.create_task(
-                self._manage_channel,
-                sync_executor=self._executor,
-                task_name=f"{self.__class__.__name__} channel refresh",
-            )
+            try:
+                self._channel_refresh_task = CrossSync.create_task(
+                    self._manage_channel,
+                    sync_executor=self._executor,
+                    task_name=f"{self.__class__.__name__} channel refresh",
+                )
+            except Exception as e:
+                _LOGGER.warning(
+                    f"Failed to start background channel refresh task: {e}. "
+                    "Channel refresh will be disabled."
+                )
+                self._channel_refresh_task = None
 
     @CrossSync.convert
     async def close(self, timeout: float | None = 2.0):
@@ -1151,18 +1158,29 @@ def __init__(
             default_retryable_errors or ()
         )
 
+        if CrossSync.is_async:
+            try:
+                CrossSync.verify_async_event_loop()
+            except RuntimeError as e:
+                raise RuntimeError(
+                    f"{self.__class__.__name__} must be created within an async event loop context."
+                ) from e
         try:
-            self._register_instance_future = CrossSync.create_task(
-                self.client._register_instance,
-                self.instance_id,
-                self.app_profile_id,
-                id(self),
-                sync_executor=self.client._executor,
+            self._register_instance_future: CrossSync.Future[None] | None = (
+                CrossSync.create_task(
+                    self.client._register_instance,
+                    self.instance_id,
+                    self.app_profile_id,
+                    id(self),
+                    sync_executor=self.client._executor,
+                )
+            )
+        except Exception as e:
+            _LOGGER.warning(
+                f"Failed to start background instance registration: {e}. "
+                "Requests will proceed without proactive channel warming."
             )
-        except RuntimeError as e:
-            raise RuntimeError(
-                f"{self.__class__.__name__} must be created within an async event loop context."
-            ) from e
+            self._register_instance_future = None
 
     def _create_operation(
         self, op_type: OperationType, **kwargs

packages/google-cloud-bigtable/google/cloud/bigtable/data/_sync_autogen/client.py

@@ -306,11 +306,17 @@ def _start_background_channel_refresh(self) -> None:
             and (not self._disable_background_refresh)
         ):
             CrossSync._Sync_Impl.verify_async_event_loop()
-            self._channel_refresh_task = CrossSync._Sync_Impl.create_task(
-                self._manage_channel,
-                sync_executor=self._executor,
-                task_name=f"{self.__class__.__name__} channel refresh",
-            )
+            try:
+                self._channel_refresh_task = CrossSync._Sync_Impl.create_task(
+                    self._manage_channel,
+                    sync_executor=self._executor,
+                    task_name=f"{self.__class__.__name__} channel refresh",
+                )
+            except Exception as e:
+                _LOGGER.warning(
+                    f"Failed to start background channel refresh task: {e}. Channel refresh will be disabled."
+                )
+                self._channel_refresh_task = None
 
     def close(self, timeout: float | None = 2.0):
         """Cancel all background tasks"""
@@ -908,17 +914,20 @@ def __init__(
             default_retryable_errors or ()
         )
         try:
-            self._register_instance_future = CrossSync._Sync_Impl.create_task(
-                self.client._register_instance,
-                self.instance_id,
-                self.app_profile_id,
-                id(self),
-                sync_executor=self.client._executor,
+            self._register_instance_future: CrossSync._Sync_Impl.Future[None] | None = (
+                CrossSync._Sync_Impl.create_task(
+                    self.client._register_instance,
+                    self.instance_id,
+                    self.app_profile_id,
+                    id(self),
+                    sync_executor=self.client._executor,
+                )
+            )
+        except Exception as e:
+            _LOGGER.warning(
+                f"Failed to start background instance registration: {e}. Requests will proceed without proactive channel warming."
             )
-        except RuntimeError as e:
-            raise RuntimeError(
-                f"{self.__class__.__name__} must be created within an async event loop context."
-            ) from e
+            self._register_instance_future = None
 
     def _create_operation(
         self, op_type: OperationType, **kwargs

packages/google-cloud-bigtable/google/cloud/bigtable/data/execute_query/_async/execute_query_iterator.py

@@ -14,6 +14,7 @@
 
 from __future__ import annotations
 
+import logging
 from typing import (
     TYPE_CHECKING,
     Any,
@@ -60,6 +61,8 @@
     "google.cloud.bigtable.data.execute_query._sync_autogen.execute_query_iterator"
 )
 
+_LOGGER = logging.getLogger(__name__)
+
 
 def _has_resume_token(response: ExecuteQueryResponse) -> bool:
     response_pb = response._pb  # proto-plus attribute retrieval is slow.
@@ -144,6 +147,13 @@ def __init__(
         )
         self._req_metadata = req_metadata
         self._column_info = column_info
+        if CrossSync.is_async:
+            try:
+                CrossSync.verify_async_event_loop()
+            except RuntimeError as e:
+                raise RuntimeError(
+                    f"{self.__class__.__name__} must be created within an async event loop context."
+                ) from e
         try:
             self._register_instance_task = CrossSync.create_task(
                 self._client._register_instance,
@@ -152,10 +162,12 @@ def __init__(
                 id(self),
                 sync_executor=self._client._executor,
             )
-        except RuntimeError as e:
-            raise RuntimeError(
-                f"{self.__class__.__name__} must be created within an async event loop context."
-            ) from e
+        except Exception as e:
+            _LOGGER.warning(
+                f"Failed to start background instance registration: {e}. "
+                "Requests will proceed without proactive channel warming."
+            )
+            self._register_instance_task = None
 
     @property
     def is_closed(self) -> bool:

packages/google-cloud-bigtable/google/cloud/bigtable/data/execute_query/_sync_autogen/execute_query_iterator.py

@@ -17,6 +17,7 @@
 
 from __future__ import annotations
 
+import logging
 from typing import TYPE_CHECKING, Any, Dict, Optional, Sequence, Tuple
 
 from google.api_core import retry as retries
@@ -46,6 +47,7 @@
 
 if TYPE_CHECKING:
     from google.cloud.bigtable.data import BigtableDataClient as DataClientType
+_LOGGER = logging.getLogger(__name__)
 
 
 def _has_resume_token(response: ExecuteQueryResponse) -> bool:
@@ -127,10 +129,11 @@ def __init__(
                 id(self),
                 sync_executor=self._client._executor,
             )
-        except RuntimeError as e:
-            raise RuntimeError(
-                f"{self.__class__.__name__} must be created within an async event loop context."
-            ) from e
+        except Exception as e:
+            _LOGGER.warning(
+                f"Failed to start background instance registration: {e}. Requests will proceed without proactive channel warming."
+            )
+            self._register_instance_task = None
 
     @property
     def is_closed(self) -> bool:

packages/google-cloud-bigtable/tests/unit/data/_async/test_client.py

@@ -404,6 +404,33 @@ async def test__start_background_channel_refresh_disable_background_refresh(self
             assert client._channel_refresh_task is None
             ping_and_warm.assert_not_called()
 
+    @CrossSync.pytest
+    async def test__start_background_channel_refresh_task_creation_failure(
+        self, caplog
+    ):
+        import logging
+
+        client = self._make_client(
+            project="project-id",
+            _disable_background_refresh=True,
+        )
+        client._disable_background_refresh = False
+        client._emulator_host = None
+        with mock.patch.object(
+            CrossSync, "create_task", side_effect=RuntimeError("can't start new thread")
+        ) as mock_create_task:
+            with caplog.at_level(logging.WARNING):
+                client._start_background_channel_refresh()
+                assert client._channel_refresh_task is None
+                assert "Failed to start background channel refresh task" in caplog.text
+                assert "can't start new thread" in caplog.text
+                mock_create_task.assert_called_once_with(
+                    client._manage_channel,
+                    sync_executor=client._executor,
+                    task_name=f"{client.__class__.__name__} channel refresh",
+                )
+        await client.close()
+
     @CrossSync.drop
     @CrossSync.pytest
     async def test__start_background_channel_refresh_task_names(self):
@@ -1507,6 +1534,31 @@ def test_table_ctor_sync(self):
             TableAsync(client, "instance-id", "table-id")
         assert e.match("TableAsync must be created within an async event loop context.")
 
+    @CrossSync.pytest
+    async def test_table_ctor_task_creation_failure_warns_and_continues(self, caplog):
+        import logging
+
+        client = self._make_client()
+        with mock.patch.object(
+            CrossSync, "create_task", side_effect=RuntimeError("can't start new thread")
+        ) as mock_create_task:
+            with caplog.at_level(logging.WARNING):
+                table = self._make_one(client)
+                assert table._register_instance_future is None
+                assert "Failed to start background instance registration" in caplog.text
+                assert "can't start new thread" in caplog.text
+                mock_create_task.assert_called_once_with(
+                    client._register_instance,
+                    table.instance_id,
+                    table.app_profile_id,
+                    id(table),
+                    sync_executor=client._executor,
+                )
+        async with table:
+            pass
+        await table.close()
+        await client.close()
+
     @CrossSync.pytest
     # iterate over all retryable rpcs
     @pytest.mark.parametrize(

packages/google-cloud-bigtable/tests/unit/data/_sync_autogen/test_client.py

@@ -346,6 +346,31 @@ def test__start_background_channel_refresh_disable_background_refresh(self):
             assert client._channel_refresh_task is None
             ping_and_warm.assert_not_called()
 
+    def test__start_background_channel_refresh_task_creation_failure(self, caplog):
+        import logging
+
+        client = self._make_client(
+            project="project-id", _disable_background_refresh=True
+        )
+        client._disable_background_refresh = False
+        client._emulator_host = None
+        with mock.patch.object(
+            CrossSync._Sync_Impl,
+            "create_task",
+            side_effect=RuntimeError("can't start new thread"),
+        ) as mock_create_task:
+            with caplog.at_level(logging.WARNING):
+                client._start_background_channel_refresh()
+                assert client._channel_refresh_task is None
+                assert "Failed to start background channel refresh task" in caplog.text
+                assert "can't start new thread" in caplog.text
+                mock_create_task.assert_called_once_with(
+                    client._manage_channel,
+                    sync_executor=client._executor,
+                    task_name=f"{client.__class__.__name__} channel refresh",
+                )
+        client.close()
+
     def test__ping_and_warm_instances(self):
         """test ping and warm with mocked asyncio.gather"""
         client_mock = mock.Mock()
@@ -1262,6 +1287,32 @@ def test_ctor_invalid_timeout_values(self):
             assert "operation_timeout must be greater than 0" in str(e.value)
         client.close()
 
+    def test_table_ctor_task_creation_failure_warns_and_continues(self, caplog):
+        import logging
+
+        client = self._make_client()
+        with mock.patch.object(
+            CrossSync._Sync_Impl,
+            "create_task",
+            side_effect=RuntimeError("can't start new thread"),
+        ) as mock_create_task:
+            with caplog.at_level(logging.WARNING):
+                table = self._make_one(client)
+                assert table._register_instance_future is None
+                assert "Failed to start background instance registration" in caplog.text
+                assert "can't start new thread" in caplog.text
+                mock_create_task.assert_called_once_with(
+                    client._register_instance,
+                    table.instance_id,
+                    table.app_profile_id,
+                    id(table),
+                    sync_executor=client._executor,
+                )
+        with table:
+            pass
+        table.close()
+        client.close()
+
     @pytest.mark.parametrize(
         "fn_name,fn_args,is_stream,extra_retryables",
         [

packages/google-cloud-bigtable/tests/unit/data/execute_query/_async/test_query_iterator.py

@@ -401,3 +401,61 @@ async def __anext__(self):
 
         # The close method should be called by the finally block on error
         client_mock._remove_instance_registration.assert_called_once()
+
+    @CrossSync.drop
+    def test_iterator_ctor_sync(self):
+        # initializing iterator in a sync context should raise RuntimeError
+        client_mock = mock.Mock()
+        client_mock._register_instance = CrossSync.Mock()
+        with pytest.raises(RuntimeError) as e:
+            self._make_one(
+                client=client_mock,
+                instance_id="test-instance",
+                app_profile_id="test_profile",
+                request_body={},
+                prepare_metadata=_pb_metadata_to_metadata_types(
+                    metadata(column("test1", int64_type()))
+                ),
+                attempt_timeout=10,
+                operation_timeout=10,
+            )
+        assert e.match(
+            f"{self._target_class().__name__} must be created within an async event loop context."
+        )
+
+    @CrossSync.pytest
+    async def test_iterator_ctor_task_creation_failure_warns_and_continues(
+        self, caplog
+    ):
+        import logging
+
+        client_mock = mock.Mock()
+        client_mock._register_instance = CrossSync.Mock()
+        client_mock._remove_instance_registration = CrossSync.Mock()
+        client_mock._executor = concurrent.futures.ThreadPoolExecutor()
+        with mock.patch.object(
+            CrossSync, "create_task", side_effect=RuntimeError("can't start new thread")
+        ) as mock_create_task:
+            with caplog.at_level(logging.WARNING):
+                iterator = self._make_one(
+                    client=client_mock,
+                    instance_id="test-instance",
+                    app_profile_id="test_profile",
+                    request_body={},
+                    prepare_metadata=_pb_metadata_to_metadata_types(
+                        metadata(column("test1", int64_type()))
+                    ),
+                    attempt_timeout=10,
+                    operation_timeout=10,
+                )
+                assert iterator._register_instance_task is None
+                assert "Failed to start background instance registration" in caplog.text
+                assert "can't start new thread" in caplog.text
+                mock_create_task.assert_called_once_with(
+                    client_mock._register_instance,
+                    "test-instance",
+                    "test_profile",
+                    id(iterator),
+                    sync_executor=client_mock._executor,
+                )
+        await iterator.close()