syntax = "proto3";
import "google/protobuf/empty.proto";

option go_package = "./postal";

enum DeliverResult {
  Success = 0;
  ReceiverOffline = 1;
}

service Postal {
  rpc Deliver(ReqDeliver) returns (ResDeliver);
  rpc DeliverBatch(ReqDeliverBatch) returns(ResDeliver);
  // broadcast request to postal cluster
  rpc DeliverGroup(ReqDeliverGroup) returns(ResDeliver);

  // rpc GroupCreate(ReqGroupCreate) returns(ResGroupCreate);
  rpc GroupJoin(ReqGroupJoin) returns(google.protobuf.Empty);
  rpc GroupLeave(ReqGroupLeave) returns(google.protobuf.Empty);
  rpc GroupDissolve(ReqGroupDissolve) returns(google.protobuf.Empty);

  // 返回当前节点外部连接断点, 如 websocket addr
  rpc Endpoint(google.protobuf.Empty) returns(ResEndpoint);
}

message Message {
  int64 time = 3;
  int32 svcNo = 4;
  int32 msgNo = 5;
  string svc = 13;
  string msg = 14;
  bytes body = 15; // protobuf bytes
}

message ReqDeliver {
  string receiver = 1;
  Message msg = 2;

  // bool sync = 7; // 是否同步阻塞等待投递结果, 默认false立即返回放到队列消费投递
}

message ResDeliver {
  bool ok = 1;
  int32 code = 2;
  string msg = 3;
}

message ReqDeliverBatch {
  repeated string receivers = 1;
  Message msg = 2;
}

message ReqDeliverGroup {
  string gid = 1;
  Message msg = 2;
}

message ReqGroupCreate {
  string gid = 1; // 群id
  map<string, string> tags = 3; // 群标签...

  bool persistent = 7; // 群关系是否持久化, 默认否
}

message ResGroupCreate {
  string gid = 1; // 群id
}

message ReqGroupJoin {
  string uid = 1;
  repeated string gids = 2;
}

message ReqGroupLeave {
  string uid = 1;
  repeated string gids = 2;
}

message ReqGroupDissolve {
  string gid = 1;
}

// 集群之间接口调用，重定向消息...
service PostalCluster {
  // socket不在当前节点，重新投递消息
  rpc Redirect(ReqRedirect) returns(ResDeliver);
}

message ReqRedirect {
  int32 ttl = 1;  // 投递一次减一, 到0丢弃
  int32 redirectMethod = 2;  // 10 deliver, 11 deliverBatch, 12 deliverGroup
  // bool sync = 7;  // 是否同步阻塞等待投递结果,否则放到channel顺序投递
  ReqDeliver  deliver = 10;
  ReqDeliverBatch  deliverBatch = 11;
  ReqDeliverGroup  deliverGroup = 12;
}

message ResEndpoint {
  string endpoint = 1;
  map<string, string> extra = 2;
}