jobserv/src/main/java/JobServ/JobServServer.java

package JobServ;

import io.grpc.Server;
import io.grpc.ServerBuilder;
import io.grpc.stub.StreamObserver;

import java.io.IOException;
import java.util.logging.Logger;

public class JobServServer {
    private static final Logger logger = Logger.getLogger(JobServServer.class.getName());

    private Server server;

    // starts the GRPC API Server
    private void start() throws IOException {
	// TODO: this should be passed in from a configuration manager
	int port = 8448;
	server = ServerBUilder.forPort(port)
	    .addService(new JobServImpl())
	    .build()
	    .start();
	logger.info("Server initialized without tls");
	Runtime.getRuntime().addShutdownHook(new thread() {
		@Override
		public void run() {
		    // JVM shutdown might break logger functionality
		    // so investigate this....
		    logger.info("Shutting down server");
		    JobServServer.this.stop();
		}
	    });
    }

    private void stop() {
	if (server != null) {
	    server.shutdown();
	}
    }

    // spinlock for main()
    private void blockUntilShutdown() throws InterruptedException {
	if (server != null) {
	    server.awaitTermination();
	}
    }

    // Main funciton. starts GRPC server and spins until server is shutdown
    public static void main(String[] args) throws IOException, InterruptedException {
	final JobServServer server = new JobServServer();
	server.start();
	server.blockUntilShutdown();
    }

    // wrap around stub code generated by GRPC
    static class JobServImpl extends JobServGrpc.JobServImplBase {
	
	@Override
	public void getStatusDetail(RequestMessage request,
				    StreamObserver<JobStatusMessage> responder) {
	    // TODO: Implement job controller, check request type, do the thing
	    JobStatusMessage reply = JobStatusMessage.newBuilder()
		.setPID(-1)
		.setProcessStatus(-1)
		.build();
	    responder.onNext(reply);
	    responder.onCompleted();
	}

	@Override
	public void getJobOutput(RequestMessage request,
				 StreamObserver<OutputMessage> responder) {
	    // TODO: Implement job controller, get output, do the thing
	    OutputMessage reply = OutputMessage.newBuilder()
		.setPID(-1)
		.setProcessOutput("Hello World!")
		.build();
	    responder.onNext(reply);
	    responder.onCompleted();
	}

	@Override
	public void makeNewJob(NewJobMessage request,
			       StreamObserver<JobStatusMessage> responder) {
	    // TODO: Implement job controller, Start Job, do the thing
	    JobStatusMessage reply = JobStatusMessage.newBuilder()
		.setPID(-1)
		.setProcessStatus(-1)
		.build():
	    responder.onNext(reply);
	    responder.onCompleted();
	}
    }
}