PubSub - doesn't work on App Engine Standard

[jerjou]

Since the pubsub client lib is all async and uses thread pools (which GAE Standard doesn't allow), the pubsub lib doesn't work on GAE Standard.

[garrettjonesgoogle]

Could you make a request for a specific change you would like to see?

[jerjou]

At a high level, I'd like our client libraries to work on GAE Standard :-) I can think of a couple options I'd be happy with:

• GAE Standard supports background threads making urlfetches (this should fix at least the problem I'm currently encountering, when trying to publish to a topic on GAE Standard). I understand this option is outside the scope of this repo :-)
• PubSub client lib otherwise gets its background threads' urlfetches working on GAE Standard (perhaps by using ThreadManager?)
• PubSub client lib exposes synchronous versions of its methods, so GAE Standard users can make calls on the main thread

[briangranatir]

You probably already know this, but this is the error that appears when trying to run the new PubSub lib on GAE Standard (I'm using Java):

Google App Engine does not support Runtime.addShutdownHook

Would be nice if the new Cloud Client Libraries all worked on GAE Standard. Thanks!

For reference, I am running the sample code from the PubSubExample

[garrettjonesgoogle]

Development since this issue was filed: Java 8 on App Engine Standard will support gRPC, so Pub/Sub should work in that environment. Unfortunately, it won't work on Java 7 and there are no plans to support that. The work to get open issues fixed for Java 8 on App Engine Standard is being tracked in #1918 . I am going to close out the present issue - follow along in #1918 for progress.