feat: add JSON-RPC control adapter

cmd/rvbox-server/main.go

@@ -80,6 +80,19 @@ func run(configPath string) error {
 	}
 	grpcServer := grpc.NewServer(grpc.MaxRecvMsgSize(int(configured.Protocol.MaxControlRequestBytes)), grpc.MaxSendMsgSize(int(configured.Protocol.MaxControlRequestBytes)))
 	rvboxv1.RegisterControlServer(grpcServer, controlService)
+	var rpcListener net.Listener
+	var rpcServer *http.Server
+	if configured.JSONRPC.Enabled {
+		rpcListener, err = net.Listen("tcp", configured.JSONRPC.Listen)
+		if err != nil {
+			return fmt.Errorf("listen for JSON-RPC: %w", err)
+		}
+		defer rpcListener.Close()
+		if configured.JSONRPC.NonLoopbackBind {
+			log.Printf("rvbox-server: WARNING JSON-RPC is unauthenticated and bound to non-loopback address %s", configured.JSONRPC.Listen)
+		}
+		rpcServer = &http.Server{Handler: control.NewJSONRPCHandler(controlService, int64(configured.Protocol.MaxJSONRPCBodyBytes)), ReadHeaderTimeout: configured.Flow.WriteDeadline}
+	}
 	agent := &session.AgentServer{
 		Store: persistence, Registry: registry, Path: configured.Server.AgentPath,
 		Limits: agentproto.Limits{
@@ -93,9 +106,12 @@ func run(configPath string) error {
 		HeartbeatIdle: configured.Protocol.HeartbeatIdle, LivenessTimeout: configured.Protocol.LivenessTimeout,
 	}
 	httpServer := &http.Server{Handler: agent, ReadHeaderTimeout: configured.Flow.WriteDeadline}
-	serveError := make(chan error, 2)
+	serveError := make(chan error, 3)
 	go func() { serveError <- httpServer.Serve(listener) }()
 	go func() { serveError <- grpcServer.Serve(controlListener) }()
+	if rpcServer != nil {
+		go func() { serveError <- rpcServer.Serve(rpcListener) }()
+	}
 
 	signals := make(chan os.Signal, 1)
 	signal.Notify(signals, os.Interrupt, syscall.SIGTERM)
@@ -103,15 +119,27 @@ func run(configPath string) error {
 	select {
 	case err := <-serveError:
 		if errors.Is(err, http.ErrServerClosed) {
+			if rpcServer != nil {
+				_ = rpcServer.Close()
+			}
 			grpcServer.Stop()
 			return nil
 		}
+		_ = httpServer.Close()
+		if rpcServer != nil {
+			_ = rpcServer.Close()
+		}
 		grpcServer.Stop()
 		return err
 	case <-signals:
 		shutdownContext, cancel := context.WithTimeout(context.Background(), configured.Server.ShutdownGrace)
 		defer cancel()
 		httpErr := httpServer.Shutdown(shutdownContext)
+		if rpcServer != nil {
+			if err := rpcServer.Shutdown(shutdownContext); httpErr == nil {
+				httpErr = err
+			}
+		}
 		grpcDone := make(chan struct{})
 		go func() { grpcServer.GracefulStop(); close(grpcDone) }()
 		select {