MaxMessageSize too low for Cloud Pub/Sub

[mdietz94]

Cloud Pub/Sub allows responses of up to 20 MB, so the channel default of 4 MB causes deframing errors for users, as can be seen here https://code.google.com/p/cloud-pubsub/issues/detail?id=50 . MaxMessageSize should either be increased to at least 20 MB, or else users should be given the ability to change it themselves.

[garrettjonesgoogle]

@pongad : I'm unsure if this is already addressed in the pubsub-hp branch.

[pongad]

This issue seems to be alleviated by grpc/grpc-java#2307 . As of GRPC 1.0.3 though, the fix hasn't been merged...

[pongad]

@garrettjonesgoogle This is now available here. It is marked experimental though. Are we OK to use this? I'm a little worried about ABI compatibility with later releases. Or do we plan to shade the entire gRPC?

[garrettjonesgoogle]

Good catch. I'm trying to get away from dependencies on experimental features. We will need to think about this.

[garrettjonesgoogle]

Filed issue grpc/grpc-java#2763 .

[garrettjonesgoogle]

Maybe we could mark it as experimental on our own surface too, so that users can make their own choice about whether to depend on it.

[garrettjonesgoogle]

Hmm ideally we wouldn't actually want to expose this on our surface, since this can be completely determined by which API is in use.

[garrettjonesgoogle]

@pongad - GAX issue: googleapis/gax-java#149 - please resolve that issue if for some reason no GAX change is necessary to support Pub/Sub.

[pongad]

@mdietz94 Sorry it took me so long to get to this. I want to make sure. This is only for Subscriber right? The Publisher is unaffected?

[mdietz94]

Yes, this is only inbound message size, so this only affects Subscriber.

[garrettjonesgoogle]

This has been fixed for a while. #1911 moved the grpc call into GAX, so that it's no longer made directly from google-cloud-java. Resolving.