02.proto示例

syntax = "proto3"; //在最上面定义使用的是proto3
package cars; //定义本文件的package名
option go_package = "trip/proto;tripPb"; //定义生成go文件的package路径，tripPb相当于生成包的别名

//定义一个消息类型，类似go的struct
message Location { 
  double lat = 1; //定义浮点数类型，字段名lat，`=1`代表顺序排在第一个
  double lon = 2;
}

message Trip{
  string            start          = 1;
  string            end            = 2;
  int64             duration_sec   = 3;
  int64             fee_cent       = 4;
  Location          start_pos      = 5; //引用上面定义的message类型，字段名start_pos，`=5`代表顺序排在第五个
  Location          end_pos        = 6; //字段名end_pos，生成go代码时会使用驼峰规则
  repeated Location path_locations = 7; //repeated定义为复合类型，类似go的slice或php的数组
  TripStatus        status         = 8; //引用下面的枚举类型，代表状态
}

//定义枚举类型
enum TripStatus { 
  IS_NOT_SPECIFIED = 0;
  NOT_START        = 1;
  IN_PROGRESS      = 2;
  FINISHED         = 3;
  PAID             = 4;
  OVER             = 5;
}

message GetTripRequest {
  string id = 1;
}

message GetTripResponse{
  string id   = 1;
  Trip   trip = 2;
}

//定义GRPC的服务端和客户端
service TripService {
  //定义服务接口GetTrip，接收参数为 GetTripRequest，返回为GetTripResponse
  rpc GetTrip (GetTripRequest) returns (GetTripResponse);
}