asserting throwing for async publish with currently errored batch

[camerondavison]

Environment details

• OS type and version: linux
• Python version: python --version : Python 3.7.6
• pip version: pip --version : pip 19.3.1
• google-cloud-pubsub version: pip show google-cloud-pubsub 1.3.1

Code example

from google.cloud import pubsub_v1
import time


def main():
    publisher = pubsub_v1.PublisherClient()
    topic_path = "projects/*****/topics/*****"

    try:
        publisher.publish(topic_path, data=b'')  # invalid
    except:
        pass

    while True:
        print('publishing')
        publisher.publish(topic_path, data=b'valid')
        time.sleep(1)


if __name__ == '__main__':
    main()

Stack trace

Traceback (most recent call last):
  File "pubsub_error.py", line 21, in <module>
    main()
  File "pubsub_error.py", line 16, in main
    publisher.publish(topic_path, data=b'valid')
  File "/Users/camerondavison/Library/Python/3.7/lib/python/site-packages/google/cloud/pubsub_v1/publisher/client.py", line 364, in publish
    future = sequencer.publish(message)
  File "/Users/camerondavison/Library/Python/3.7/lib/python/site-packages/google/cloud/pubsub_v1/publisher/_sequencer/unordered_sequencer.py", line 113, in publish
    future = batch.publish(message)
  File "/Users/camerondavison/Library/Python/3.7/lib/python/site-packages/google/cloud/pubsub_v1/publisher/_batch/thread.py", line 334, in publish
    ), "Publish after stop() or publish error."
AssertionError: Publish after stop() or publish error.

As I mentioned just now in #26 (comment) it looks like there is an assert that was added that can now trigger for an errored out batch.

batch errors could happen any time so it seems like it would be better to move the assert below the check to see if the batch is still accepting new messages so that a new batch can be created if it errored out.

I validated the same code does not throw an exception on publish in 1.2.0

[pradn]

Cameron, thanks for the detailed bug report. I've just submitted a PR to fix the underlying issue.

[pradn]

We'll do a bugfix release early next week.

[pradn]

The fix is out in version 1.4.1.