handle error

network/grpc/grpc.go

@@ -76,7 +76,7 @@ func interceptor(
 	)
 }
 
-func (g *GrpcStream) Client(ctx context.Context, stream network.Stream) *grpc.ClientConn {
+func (g *GrpcStream) Client(ctx context.Context, stream network.Stream) (*grpc.ClientConn, error) {
 	return WrapClient(ctx, stream)
 }
 
@@ -128,7 +128,7 @@ func (g *GrpcStream) Close() error {
 
 // --- conn ---
 
-func WrapClient(ctx context.Context, s network.Stream) *grpc.ClientConn {
+func WrapClient(ctx context.Context, s network.Stream) (*grpc.ClientConn, error) {
 	opts := grpc.WithContextDialer(func(ctx context.Context, peerIdStr string) (net.Conn, error) {
 		return &streamConn{s}, nil
 	})
@@ -145,11 +145,10 @@ func WrapClient(ctx context.Context, s network.Stream) *grpc.ClientConn {
 		opts)
 
 	if err != nil {
-		// TODO: this should not fail at all
-		panic(err)
+		return nil, err
 	}
 
-	return conn
+	return conn, nil
 }
 
 // streamConn represents a net.Conn wrapped to be compatible with net.conn

network/interface.go

@@ -55,7 +55,7 @@ type Network interface {
 }
 
 type Protocol interface {
-	Client(context.Context, network.Stream) *rawGrpc.ClientConn
+	Client(context.Context, network.Stream) (*rawGrpc.ClientConn, error)
 	Handler() func(network.Stream)
 }
 

network/server.go

@@ -784,8 +784,14 @@ func (s *DefaultServer) NewProtoConnection(
 
 	s.logger.Debug("create grpc client", "protocol", protocol, "peer", peerID)
 
-	// don't need context.WithTimeout, rpc client is fake
-	return p.Client(ctx, stream), nil
+	clt, err := p.Client(ctx, stream)
+	if err != nil {
+		s.logger.Error("create grpc client failed", "protocol", protocol, "peer", peerID, "err", err)
+
+		return nil, err
+	}
+
+	return clt, nil
 }
 
 func (s *DefaultServer) GetMetrics() *Metrics {