/*
 * Copyright 2024, gRPC 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 = "proto3";

// A controllable service for testing.
//
// The control service has one RPC of each kind, the input to each RPC controls
// the output.
service Control {
  rpc Unary(ControlInput) returns (ControlOutput) {}
  rpc ServerStream(ControlInput) returns (stream ControlOutput) {}
  rpc ClientStream(stream ControlInput) returns (ControlOutput) {}
  rpc BidiStream(stream ControlInput) returns (stream ControlOutput) {}
}

message ControlInput {
  // Whether metadata should be echo'd back in the initial metadata.
  //
  // Ignored if the initial metadata has already been sent back to the
  // client.
  //
  // Each header field name in the request headers will be prefixed with
  // "echo-". For example the header field name "foo" will be returned
  // as "echo-foo. Note that semicolons aren't valid in HTTP header field
  // names (apart from pseudo headers). As such all semicolons should be
  // removed (":path" should become "echo-path").
  bool echo_metadata_in_headers = 1;

  // Parameters for response messages.
  PayloadParameters message_params = 2;

  // The number of response messages.
  int32 number_of_messages = 3;

  // The status code and message to use at the end of the RPC.
  //
  // If this is set then the RPC will be ended after `number_of_messages`
  // messages have been sent back to the client.
  RPCStatus status = 5;

  // Whether the response should be trailers only.
  //
  // Ignored unless it's set on the first message on the stream. When set
  // the RPC will be completed with a trailers-only response using the
  // status code and message from 'status'. The request metadata will be
  // included if 'echo_metadata_in_trailers' is set.
  //
  // If this is set then 'number_of_messages', 'message_params', and
  // 'echo_metadata_in_headers' are ignored.
  bool is_trailers_only = 6;

  // Whether metadata should be echo'd back in the trailing metadata.
  //
  // Ignored unless 'status' is set.
  //
  // Each header field name in the request headers will be prefixed with
  // "echo-". For example the header field name "foo" will be returned
  // as "echo-foo. Note that semicolons aren't valid in HTTP header field
  // names (apart from pseudo headers). As such all semicolons should be
  // removed (":path" should become "echo-path").
  bool echo_metadata_in_trailers = 4;
}

message RPCStatus {
  // Status code indicating the outcome of the RPC.
  StatusCode code = 1;

  // The message to include with the 'code' at the end of the RPC.
  string message = 2;
}

enum StatusCode {
  OK = 0;
  CANCELLED = 1;
  UNKNOWN = 2;
  INVALID_ARGUMENT = 3;
  DEADLINE_EXCEEDED = 4;
  NOT_FOUND = 5;
  ALREADY_EXISTS = 6;
  PERMISSION_DENIED = 7;
  RESOURCE_EXHAUSTED = 8;
  FAILED_PRECONDITION = 9;
  ABORTED = 10;
  OUT_OF_RANGE = 11;
  UNIMPLEMENTED = 12;
  INTERNAL = 13;
  UNAVAILABLE = 14;
  DATA_LOSS = 15;
  UNAUTHENTICATED = 16;
}

message PayloadParameters {
  // The number of bytes to put into the output payload.
  int32 size = 1;

  // The content to use in the payload. The value is truncated to an octet.
  uint32 content = 2;
}

message ControlOutput {
  bytes payload = 1;
}