遇到proto编译问问，看看proto语法，记录一下
protobuf3 语法指南
http://colobu.com/2017/03/16/Protobuf3-language-guide/
https://developers.google.com/protocol-buffers/docs/proto3?hl=zh-cn#generating
protobuf2 语法指南
http://colobu.com/2015/01/07/Protobuf-language-guide/
https://developers.google.com/protocol-buffers/docs/proto
原文：https://www.cnblogs.com/xudong-bupt/p/9363904.html