// Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

syntax = "proto2";
package paddle.distributed;
option cc_generic_services = true;
option cc_enable_arenas = true;

enum MessageType {
  STOP = 1;            // STOP an Interceptor
  DATA_IS_READY = 2;   // upstream data is ready
  DATA_IS_USELESS = 3; // downstream has used the data
  ERR = 4;             // current Interceptor encounters error
  RESET = 5;           // reset the status
  START = 6;
}

message InterceptorMessage {
  optional sint64 src_id = 1 [ default = 0 ];
  optional sint64 dst_id = 2 [ default = 0 ];
  optional MessageType message_type = 3 [ default = RESET ];
  optional bool ctrl_message = 4 [ default = false ];
  optional int64 scope_idx = 5 [ default = 0 ];
}

message InterceptorResponse { optional bool rst = 1 [ default = false ]; }

service MessageService {
  rpc ReceiveInterceptorMessage(InterceptorMessage)
      returns (InterceptorResponse);
  rpc IncreaseBarrierCount(InterceptorMessage) returns (InterceptorResponse);
}