// Copyright 2018, OpenCensus Authors
//
// 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";

// NOTE: This proto is experimental and is subject to change at this point.
// Please do not use it at the moment.

package opencensus.proto.agent.common.v1;

import "google/protobuf/timestamp.proto";

option java_multiple_files = true;
option java_package = "io.opencensus.proto.agent.common.v1";
option java_outer_classname = "CommonProto";

option go_package = "github.com/census-instrumentation/opencensus-proto/gen-go/agent/common/v1";

// Identifier metadata of the Node that produces the span or tracing data.
// Note, this is not the metadata about the Node or service that is described by associated spans.
// In the future we plan to extend the identifier proto definition to support
// additional information (e.g cloud id, etc.)
message Node {
  // Identifier that uniquely identifies a process within a VM/container.
  ProcessIdentifier identifier = 1;

  // Information on the OpenCensus Library that initiates the stream.
  LibraryInfo library_info = 2;

  // Additional information on service.
  ServiceInfo service_info = 3;

  // Additional attributes.
  map<string, string> attributes = 4;

  // TODO(songya): Add more identifiers in the future as needed, like cloud
  // identifiers.
}

// Identifier that uniquely identifies a process within a VM/container.
message ProcessIdentifier {

  // The host name. Usually refers to the machine/container name.
  // For example: os.Hostname() in Go, socket.gethostname() in Python.
  string host_name = 1;

  // Process id.
  uint32 pid = 2;

  // Start time of this ProcessIdentifier. Represented in epoch time.
  google.protobuf.Timestamp start_timestamp = 3;
}

// Information on OpenCensus Library.
message LibraryInfo {

  enum Language {
    LANGUAGE_UNSPECIFIED = 0;
    CPP = 1;
    C_SHARP = 2;
    ERLANG = 3;
    GO_LANG = 4;
    JAVA = 5;
    NODE_JS = 6;
    PHP = 7;
    PYTHON = 8;
    RUBY = 9;
  }

  // Language of OpenCensus Library.
  Language language = 1;

  // Version of Agent exporter of Library.
  string exporter_version = 2;

  // Version of OpenCensus Library.
  string core_library_version = 3;
}

// Additional service information.
message ServiceInfo {

  // Name of the service.
  string name = 1;

  // TODO(songya): add more fields as needed.
}
