syntax = "proto3";

package envoy;

message HotRestartMessage {
  // Child->parent requests
  message Request {
    message PassListenSocket {
      string address = 1;
    }
    message ShutdownAdmin {
    }
    message Stats {
    }
    message DrainListeners {
    }
    message Terminate {
    }
    oneof request {
      PassListenSocket pass_listen_socket = 1;
      ShutdownAdmin shutdown_admin = 2;
      Stats stats = 3;
      DrainListeners drain_listeners = 4;
      Terminate terminate = 5;
    }
  }

  // Parent->child replies
  message Reply {
    message PassListenSocket {
      int32 fd = 1;
    }
    message ShutdownAdmin {
      uint64 original_start_time_unix_seconds = 1;
    }
    message Span {
      uint32 first = 1;
      uint32 last = 2; // inclusive
    }
    message RepeatedSpan {
      repeated Span spans = 1;
    }
    message Stats {
      // Values for server_stats, which don't fit with the "combination logic" approach.
      uint64 memory_allocated = 1;
      uint64 num_connections = 2;

      // Keys are fully qualified stat names.
      //
      // The amount added to the counter since the last time a message included the counter in this
      // map. (The first time a counter is included in this map, it's the amount added since the
      // final latch() before hot restart began).
      map<string, uint64> counter_deltas = 3;
      // The parent's current values for various gauges in its stats store.
      map<string, uint64> gauges = 4;
      // Maps the string representation of a StatName into an array of Spans,
      // which indicate which of the StatName tokens are dynamic. For example,
      // if we are recording a counter or gauge named "a.b.c.d.e.f", where "a",
      // and "d.e" were created from a StatNameDynamicPool, then we'd map
      // "a.b.c.d.e.f" to the span array [[0,0], [3,4]], where the [0,0] span
      // covers the "a", and the [3,4] span covers "d.e".
      map<string, RepeatedSpan> dynamics = 5;
    }
    oneof reply {
      // When this oneof is of the PassListenSocketReply type, there is a special
      // implied meaning: the recvmsg that got this proto has control data to make
      // the passing of the fd work, so make use of CMSG_SPACE etc.
      PassListenSocket pass_listen_socket = 1;
      ShutdownAdmin shutdown_admin = 2;
      Stats stats = 3;
    }
  }

  oneof requestreply {
    Request request = 1;
    Reply reply = 2;
  }

  bool didnt_recognize_your_last_message = 3;
}