syntax = "proto3";

package envoy.type;

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

import "udpa/annotations/status.proto";
import "validate/validate.proto";

option java_package = "io.envoyproxy.envoy.type";
option java_outer_classname = "TokenBucketProto";
option java_multiple_files = true;
option go_package = "github.com/envoyproxy/go-control-plane/envoy/type";
option (udpa.annotations.file_status).package_version_status = FROZEN;

// [#protodoc-title: Token bucket]

// Configures a token bucket, typically used for rate limiting.
message TokenBucket {
  // The maximum tokens that the bucket can hold. This is also the number of tokens that the bucket
  // initially contains.
  uint32 max_tokens = 1 [(validate.rules).uint32 = {gt: 0}];

  // The number of tokens added to the bucket during each fill interval. If not specified, defaults
  // to a single token.
  google.protobuf.UInt32Value tokens_per_fill = 2 [(validate.rules).uint32 = {gt: 0}];

  // The fill interval that tokens are added to the bucket. During each fill interval
  // `tokens_per_fill` are added to the bucket. The bucket will never contain more than
  // `max_tokens` tokens.
  google.protobuf.Duration fill_interval = 3 [(validate.rules).duration = {
    required: true
    gt {}
  }];
}