syntax = "proto3";

package tensorflow;
option cc_enable_arenas = true;
option java_outer_classname = "EventProtos";
option java_multiple_files = true;
option java_package = "org.tensorflow.util";

import "tensorflow/core/framework/summary.proto";

// Protocol buffer representing an event that happened during
// the execution of a Brain model.
message Event {
  // Timestamp of the event.
  double wall_time = 1;

  // Global step of the event.
  int64 step = 2;

  oneof what {
    // An event file was started, with the specified version.
    // This is use to identify the contents of the record IO files
    // easily.  Current version is "brain.Event:2".  All versions
    // start with "brain.Event:".
    string file_version = 3;
    // An encoded version of a GraphDef.
    bytes graph_def = 4;
    // A summary was generated.
    Summary summary = 5;
    // The user output a log message. Not all messages are logged, only ones
    // generated via the Python tensorboard_logging module.
    LogMessage log_message = 6;
    // The state of the session which can be used for restarting after crashes.
    SessionLog session_log = 7;
    // The metadata returned by running a session.run() call.
    TaggedRunMetadata tagged_run_metadata = 8;
    // An encoded version of a MetaGraphDef.
    bytes meta_graph_def = 9;
  }
}

// Protocol buffer used for logging messages to the events file.
message LogMessage {
  enum Level {
    UNKNOWN = 0;
    // Note: The logging level 10 cannot be named DEBUG. Some software
    // projects compile their C/C++ code with -DDEBUG in debug builds. So the
    // C++ code generated from this file should not have an identifier named
    // DEBUG.
    DEBUGGING = 10;
    INFO = 20;
    WARN = 30;
    ERROR = 40;
    FATAL = 50;
  }
  Level level = 1;
  string message = 2;
}

// Protocol buffer used for logging session state.
message SessionLog {
  enum SessionStatus {
    STATUS_UNSPECIFIED = 0;
    START = 1;
    STOP = 2;
    CHECKPOINT = 3;
  }

  SessionStatus status = 1;
  // This checkpoint_path contains both the path and filename.
  string checkpoint_path = 2;
  string msg = 3;
}

// For logging the metadata output for a single session.run() call.
message TaggedRunMetadata {
  // Tag name associated with this metadata.
  string tag = 1;
  // Byte-encoded version of the `RunMetadata` proto in order to allow lazy
  // deserialization.
  bytes run_metadata = 2;
}

// Worker heartbeat messages.  Support for these operations is currently
// internal and expected to change.

// Current health status of a worker.
enum WorkerHealth {
  OK = 0;  // By default a worker is healthy.
  RECEIVED_SHUTDOWN_SIGNAL = 1;
  INTERNAL_ERROR = 2;
}

// Indicates the behavior of the worker when an internal error or shutdown
// signal is received.
enum WorkerShutdownMode {
  DEFAULT = 0;
  SHUTDOWN_IMMEDIATELY = 1;
  WAIT_FOR_COORDINATOR = 2;
}

message WatchdogConfig {
  int64 timeout_ms = 1;
}

message WorkerHeartbeatRequest {
  WorkerShutdownMode shutdown_mode = 1;
  WatchdogConfig watchdog_config = 2;
}

message WorkerHeartbeatResponse {
  WorkerHealth health_status = 1;
  repeated Event worker_log = 2;
  string hostname = 3;
}