Adr*_*ian 12 go protocol-buffers grpc

google/protobuf/timestamp.protoprotoc
protoc -I  ./   ./*.proto --go_out=plugins=grpc:.
.proto
#domain.proto
syntax = "proto3";
option java_multiple_files = true;
option java_package = "com.viant.xyz";
option java_outer_classname = "domain";

import "google/protobuf/timestamp.proto";

message Foo {
    Timestamp modifiedTime = 1;
    ...
}

我看到以下错误:

domain.proto: Import "google/protobuf/timestamp.proto" was not found or had errors.
domain.proto:44:5: "Timestamp" is not defined.

我错过了什么,或者还没有支持?