// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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.

// This protobuf definition file actually requires protobuf3 despite using
// protobuf2 syntax.
syntax = "proto2";
package kudu.subprocess;

option java_package = "org.apache.kudu.subprocess";

import "google/protobuf/any.proto";
import "kudu/common/wire_protocol.proto";

// EchoResponsePB simply echoes the data in EchoRequestPB as a response.
message EchoRequestPB {
  required string data = 1;

  // Optional amount of time in milliseconds to sleep for.
  optional int32 sleep_ms = 2;
}
message EchoResponsePB {
  required string data = 1;
}

// Metrics for the subprocess subsystem.
message SubprocessMetricsPB {
  // Amount of time the request spent in the subprocess's inbound queue before
  // being serviced.
  optional int64 inbound_queue_time_ms = 1;

  // Amount of time the response spent in the subprocess's outbound queue
  // before being sent over the pipe.
  optional int64 outbound_queue_time_ms = 2;

  // Number of requests in the subprocess's inbound queue at the time the
  // response is being returned from the subprocess.
  optional int64 inbound_queue_length = 3;

  // Number of responses in the subprocess's outbound queue at the time the
  // response is being returned from the subprocess.
  optional int64 outbound_queue_length = 4;

  // The amount of time it took to execute the request (i.e. the time in
  // between waiting in the inbound and outbound queues).
  optional int64 execution_time_ms = 5;
}

// Request sent to the subprocess.
message SubprocessRequestPB {
  // A sequence number that uniquely identifies a call to the subprocess. This
  // number is sent back in the Response and allows to match it to the original
  // Request.
  optional int64 id = 1;

  // The request.
  optional google.protobuf.Any request = 3;
}

// Sent by the subprocess in response to a request.
message SubprocessResponsePB {
  optional int64 id = 1;

  // Only set if there was some kind of subprocess-side error.
  optional AppStatusPB error = 2;

  // The subprocess response. Only set for requests that actually expect a
  // response.
  optional google.protobuf.Any response = 3;

  // Metrics for the generic subprocess subsystem.
  optional SubprocessMetricsPB metrics = 4;
}