syntax = "proto3";

import "api/address.proto";

import "google/protobuf/struct.proto";
import "google/protobuf/wrappers.proto";

// Identifies location of where either Envoy runs or where upstream hosts run.
message Locality {
  // Region this zone belongs to.
  string region = 1;

  // Availability Zone (AZ) in AWS, Zone in GCP.
  string zone = 2;

  // When used for locality of upstream hosts, this field further splits zone
  // into smaller chunks of sub_zones so they can be load balanced
  // independently
  string sub_zone = 3;
}

// Identifies a specific Envoy instance. Remote server may have per Envoy configuration.
message Node {
  string id = 1;
  google.protobuf.Struct metadata = 2;
  Locality locality = 3;
}

message Duration {
  google.protobuf.UInt32Value milliseconds = 1;
}

message Endpoint {
  ResolvedAddress address = 1;
}