rpc-java | netty rpc which supports multi protocols | Websocket library

But what is generic version of SOME_GENERIC_KEY.get()? I tried Context.current().keyValueEntries but cannot compile(not public).

Context purposefully does not allow iterating over the keys, as this allows using Java visibility to restrict access to setting/getting particular keys. This produces similar results to ThreadLocal. Keys use the Java-default identity equality (k1 == k2), and the string passed to Context.key(KEY_KNOWN) is a debug string unused during get()s.

While Context is a Map-like data structure, it isn't intended as a general-purpose map as it is immutable and storing many related keys is better served with a normal HashMap or POJO.

Then how do you store many keys, one for each header that you found in Metadata? Use a Map. Create a Map with the entries found and store that map in a Context.Key> key.

I can't explain the real root of the problem but the thing that helped me is providing different ports for the server and gRPC, hope it will help someone

Looks like the path of proto file is not correcttly. Try to move proto files to src/main/resouces/proto or set path in protobuf plugin configuration.

This is works well with kotlin DSL.

You are missing the protobuf-java dependency.

The documentation recommends to checkout a git tag:

You are strongly encouraged to check out a git release tag, since there will already be a build of grpc available

gRPC-Go's codegen (https://github.com/grpc/grpc-go/tree/master/cmd/protoc-gen-go-grpc) is picked up by protoc automatically instead of specified in the --plugin flag (maybe there is a way, but I've never tried).

First you need to install protoc-gen-go-grpc plugin following the gRPC quickstart. Make sure the plugin is in PATH.

Then use the protoc-gen-go-grpc plugin in the same way for protoc builtins:

Once the server receives the StreamObserver for responses to the client it can call the object from any thread at any time (although the object is not thread-safe, so concurrent calls are not permitted). There's no need to couple it with incoming requests in onNext().

The client calling onComplete() is normal and does not end the RPC. If your code turns around and calls onComplete(), however, at that point you can no longer send any more messages on the stream. You will probably want to observe client cancellations, which can be achieved by casting the StreamObserver to ServerCallStreamObserver and calling setOnCancelHandler(Runnable) at the start of the RPC.

If you are not using the latest version, try updating to it. It looks similar to this issue that was fixed recently. I would imagine the error message still showing up, but the job now finishing means that the support team is still working on it and hopefully they will fix it in the next release.

io.grpc.* is in grpc-api (which most other grpc dependencies will depend on). io.grpc.stub.* is in grpc-stub. io.grpc.protobuf.* is in grpc-protobuf. javax.annotation.Generated can be found in Tomcat's annotations-api.

So you need to add (as mentioned in the grpc-java readme):