Closed subscriber should raise an error if used as context manager #484
Description
Environment details
- OS type and version: Linux Ubuntu 20.04
- Python version: Python 3.8.10
- pip version: pip 20.0.2 from /usr/lib/python3/dist-packages/pip (python 3.8)
google-cloud-pubsubversion:
Name: google-cloud-pubsub
Version: 2.7.1
Summary: Google Cloud Pub/Sub API client library
Home-page: https://github.com/googleapis/python-pubsub
Author: Google LLC
Author-email: googleapis-packages@google.com
License: Apache 2.0
Location: /usr/local/lib/python3.8/dist-packages
Requires: proto-plus, grpc-google-iam-v1, packaging, google-api-core, libcst, grpcio
Required-by:
Steps to reproduce
- Setup example code as below
- Run example code
I have also verified that everything is working for me by running the equivalent code in GO and I can read messages from my PubSub subscription OK.
This problem has appeared before here; #176
It seems that it either was never fixed or has come back.
Code example
#------------------------------------------------------------------------
# Example code to create pull subscription to cdr_intl
# and print the results
#------------------------------------------------------------------------
from google.cloud import pubsub_v1
from concurrent.futures import TimeoutError
project_id = "the-project"
topic_id = "the-topic"
subscription_id = "the-sub"
# Number of seconds the subscriber should listen for messages
timeout = 5.0
publisher = pubsub_v1.PublisherClient()
subscriber = pubsub_v1.SubscriberClient()
topic_path = publisher.topic_path(project_id, topic_id)
# The `subscription_path` method creates a fully qualified identifier
# in the form `projects/{project_id}/subscriptions/{subscription_id}`
subscription_path = subscriber.subscription_path(project_id, subscription_id)
#------------------------------------------------------------------------
# Create the subscription
#------------------------------------------------------------------------
# Wrap the subscriber in a 'with' block to automatically call close() to
# close the underlying gRPC channel when done.
with subscriber:
try:
subscription = subscriber.create_subscription(
request={"name": subscription_path, "topic": topic_path}
)
print(f"Subscription created: {subscription}")
except:
print(f"Subscription already exists: {subscription_id}")
#------------------------------------------------------------------------
# Read messages
#------------------------------------------------------------------------
def callback(message: pubsub_v1.subscriber.message.Message) -> None:
print(f"Received {message}.")
message.ack()
streaming_pull_future = subscriber.subscribe(subscription_path, callback=callback)
print(f"Listening for messages on {subscription_path}..\n")
# Wrap subscriber in a 'with' block to automatically call close() when done.
with subscriber:
try:
# When `timeout` is not set, result() will block indefinitely,
# unless an exception is encountered first.
streaming_pull_future.result(timeout=timeout)
except TimeoutError:
streaming_pull_future.cancel() # Trigger the shutdown.
streaming_pull_future.result() # Block until the shutdown is complete.Stack trace
Thread-ConsumeBidirectionalStream caught unexpected exception Cannot invoke RPC: Channel closed! and will exit.
Traceback (most recent call last):
File "/usr/local/lib/python3.8/dist-packages/google/api_core/bidi.py", line 637, in _thread_main
self._bidi_rpc.open()
File "/usr/local/lib/python3.8/dist-packages/google/api_core/bidi.py", line 280, in open
call = self._start_rpc(iter(request_generator), metadata=self._rpc_metadata)
File "/usr/local/lib/python3.8/dist-packages/google/pubsub_v1/services/subscriber/client.py", line 1184, in streaming_pull
response = rpc(requests, retry=retry, timeout=timeout, metadata=metadata,)
File "/usr/local/lib/python3.8/dist-packages/google/api_core/gapic_v1/method.py", line 145, in __call__
return wrapped_func(*args, **kwargs)
File "/usr/local/lib/python3.8/dist-packages/google/api_core/retry.py", line 285, in retry_wrapped_func
return retry_target(
File "/usr/local/lib/python3.8/dist-packages/google/api_core/retry.py", line 188, in retry_target
return target()
File "/usr/local/lib/python3.8/dist-packages/google/api_core/grpc_helpers.py", line 154, in error_remapped_callable
result = callable_(*args, **kwargs)
File "/usr/local/lib/python3.8/dist-packages/grpc/_channel.py", line 1205, in __call__
call = self._managed_call(
File "/usr/local/lib/python3.8/dist-packages/grpc/_channel.py", line 1301, in create
call = state.channel.integrated_call(flags, method, host, deadline,
File "src/python/grpcio/grpc/_cython/_cygrpc/channel.pyx.pxi", line 476, in grpc._cython.cygrpc.Channel.integrated_call
File "src/python/grpcio/grpc/_cython/_cygrpc/channel.pyx.pxi", line 294, in grpc._cython.cygrpc._integrated_call
File "src/python/grpcio/grpc/_cython/_cygrpc/channel.pyx.pxi", line 218, in grpc._cython.cygrpc._call
File "src/python/grpcio/grpc/_cython/_cygrpc/channel.pyx.pxi", line 258, in grpc._cython.cygrpc._call
ValueError: Cannot invoke RPC: Channel closed!