Protobuf 4

[LarsSven]

I had a quick question, why is Quarkus still using Protobuf 3.25.5 rather than using something like Protobuf 4.26 or higher?

I know there used to be some pretty big issues with migrating to the protobuf 4 releases, but I thought they got fixed.

I am asking because we wanted to use a protobuf 4 dependency but noticed that Quarkus gRPC was at 3.25.5, and I couldn't find any issue / PR really mentioning the current status of the protobuf version

[gsmet]

/cc @cescoffier @alesj

[cescoffier]

There is still quite some work to do to support Protobuf 4. Typically, we need to rewrite the code generator used to generate Mutiny interfaces. I can't say when it will be done.

There are also several breaking changes. They will require applications dealing with the Protobuf API (and the generated Java code) to update to the new API.

[cescoffier]

Of course, contributions are welcome.

[LarsSven]

Ah okay, that makes a lot of sense, thank you.

But you are planning to some day upgrade to Protobuf 4?

[cescoffier]

Yes, it's planned, but I can't say when.