// Copyright 2025 Envoy Project 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";

package envoy.type.v3;

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

option java_package = "io.envoyproxy.envoy.type.v3";
option java_outer_classname = "HashPolicyProto";
option java_multiple_files = true;
option go_package = "github.com/envoyproxy/go-control-plane/envoy/type/v3;typev3";
option (udpa.annotations.file_status).package_version_status = ACTIVE;

// [#protodoc-title: Hash Policy]

// Specifies the hash policy
message HashPolicy {
  option (udpa.annotations.versioning).previous_message_type = "envoy.type.HashPolicy";

  // The source IP will be used to compute the hash used by hash-based load balancing
  // algorithms.
  message SourceIp {
    option (udpa.annotations.versioning).previous_message_type = "envoy.type.HashPolicy.SourceIp";
  }

  // An Object in the :ref:`filterState <arch_overview_data_sharing_between_filters>` will be used
  // to compute the hash used by hash-based load balancing algorithms.
  message FilterState {
    // The name of the Object in the filterState, which is an Envoy::Hashable object. If there is no
    // data associated with the key, or the stored object is not Envoy::Hashable, no hash will be
    // produced.
    string key = 1 [(validate.rules).string = {min_len: 1}];
  }

  oneof policy_specifier {
    option (validate.required) = true;

    SourceIp source_ip = 1;

    FilterState filter_state = 2;
  }
}
