Feat/grpc transcoding

[GreyPlane]

inherit the work from #1583 since it's likely abandoned

[lightbend-cla-validator]

Hi @WayneWang12,

Thank you for your contribution! We really value the time you've taken to put this together.

We see that you have signed the Lightbend Contributors License Agreement before, however, the CLA has changed since you last signed it. Please review the new CLA and sign it before we proceed with reviewing this pull request:

https://www.lightbend.com/contribute/cla

[lightbend-cla-validator]

Hi @WayneWang12,

Thank you for your contribution! We really value the time you've taken to put this together.

We see that you have signed the Lightbend Contributors License Agreement before, however, the CLA has changed since you last signed it. Please review the new CLA and sign it before we proceed with reviewing this pull request:

https://www.lightbend.com/contribute/cla

[GreyPlane]

weird blocking issue scalapb/ScalaPB#1583

[lightbend-cla-validator]

Hi @WayneWang12,

Thank you for your contribution! We really value the time you've taken to put this together.

We see that you have signed the Lightbend Contributors License Agreement before, however, the CLA has changed since you last signed it. Please review the new CLA and sign it before we proceed with reviewing this pull request:

https://www.lightbend.com/contribute/cla

[lightbend-cla-validator]

Hi @WayneWang12,

Thank you for your contribution! We really value the time you've taken to put this together.

We see that you have signed the Lightbend Contributors License Agreement before, however, the CLA has changed since you last signed it. Please review the new CLA and sign it before we proceed with reviewing this pull request:

https://www.lightbend.com/contribute/cla

[lightbend-cla-validator]

Hi @WayneWang12,

Thank you for your contribution! We really value the time you've taken to put this together.

We see that you have signed the Lightbend Contributors License Agreement before, however, the CLA has changed since you last signed it. Please review the new CLA and sign it before we proceed with reviewing this pull request:

https://www.lightbend.com/contribute/cla

[GreyPlane]

I think this is ready to go, the implementation itself is stable enough to review, while I'm still working on adding more tests and documentations.

[johanandren]

Nice to see work here but just so you know: we don't quite have the bandwidth to properly keep up with reviewing this PR right now, so don't think of it as something that will get merged soon.

[GreyPlane]

Nice to see work here but just so you know: we don't quite have the bandwidth to properly keep up with reviewing this PR right now, so don't think of it as something that will get merged soon.

That's understandable, just knowing you guys are interested on this is enough.

[lightbend-cla-validator]

Hi @WayneWang12,

Thank you for your contribution! We really value the time you've taken to put this together.

We see that you have signed the Lightbend Contributors License Agreement before, however, the CLA has changed since you last signed it. Please review the new CLA and sign it before we proceed with reviewing this pull request:

https://www.lightbend.com/contribute/cla

[GreyPlane]

• Gradle plugin wouldn't generate ScalaPB classes for library protos, which causes generated Scala proto classes(user side) failed to use HTTP transcoding related proto classes, I've added these into protoSrc, but not very confident it's the right thing to do.
• Scripted test reported huge duplicated generated proto classes, mainly from google.api.*, which I haven't figure out how to deal with.

I think these two are the remaining blocker, but it's hard to solve due I'm lacking relative experience, so any help or suggestion was appreciate.