GrpcServerService.java

package gae.piaz.grpc.server;

import gae.piaz.grpc.lib.HelloReply;
import gae.piaz.grpc.lib.HelloRequest;
import gae.piaz.grpc.lib.SimpleGrpc;
import io.grpc.stub.StreamObserver;
import net.devh.boot.grpc.server.service.GrpcService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@GrpcService
public class GrpcServerService extends SimpleGrpc.SimpleImplBase {

    private static final Logger log = LoggerFactory.getLogger(GrpcServerService.class);

    @Override
    public void sayHello(HelloRequest req, StreamObserver<HelloReply> responseObserver) {
        log.info("say hello called");
        HelloReply reply = HelloReply.newBuilder().setMessage("Hello ==> " + req.getName()).build();
        responseObserver.onNext(reply);
        responseObserver.onCompleted();
    }

}

Related to medium article: https://gae-piaz.medium.com/springboot-with-grpc-fast-start-implementation-f8881fda0973