Topic.flush() returns immediately, before all items are published

[feywind]

Topic.flush() is promisified, so it returns either a Promise or takes a callback, depending on how it's called. This calls Publisher.flush(), which likewise can deal with Promises. However, MessageQueue.publish(), which Publisher.flush() calls, does not support Promises, only callbacks. But Publisher.flush() is expecting it to support Promises, so no callback is passed down, and Publisher.flush() gets back undefined, which passes through as a resolve, and no wait happens.

[feywind]

Relevant code bit: https://github.com/googleapis/nodejs-pubsub/blob/main/src/publisher/message-queues.ts#L162

[baeminbo]

A public issue tracker is created for this issue: https://issuetracker.google.com/issues/246207643

[feywind]

Actually, a related issue: #1463

[feywind]

I think I was looking at the wrong branch or something, because this does actually promisify the calls: https://github.com/googleapis/nodejs-pubsub/blob/main/src/publisher/index.ts#L113

That was fixed by this PR: e494fb7

...which would've been in release 2.9.0.

So I need to re-study the original problem and see if there's something else.

[feywind]

I found some possibilities. Please give this a try and see if it does what's needed, and if not, I'll reopen.