// 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.extensions.filters.http.cdn_loop.v3;

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

option java_package = "io.envoyproxy.envoy.extensions.filters.http.cdn_loop.v3";
option java_outer_classname = "CdnLoopProto";
option java_multiple_files = true;
option go_package = "github.com/envoyproxy/go-control-plane/envoy/extensions/filters/http/cdn_loop/v3;cdn_loopv3";
option (udpa.annotations.file_status).package_version_status = ACTIVE;

// [#protodoc-title: HTTP CDN-Loop Filter]
// [#extension: envoy.filters.http.cdn_loop]

// CDN-Loop Header filter config. See the :ref:`configuration overview
// <config_http_filters_cdn_loop>` for more information.
message CdnLoopConfig {
  // The CDN identifier to use for loop checks and to append to the
  // CDN-Loop header.
  //
  // RFC 8586 calls this the cdn-id. The cdn-id can either be a
  // pseudonym or hostname the CDN is in control of.
  //
  // cdn_id must not be empty.
  string cdn_id = 1 [(validate.rules).string = {min_len: 1}];

  // The maximum allowed count of cdn_id in the downstream CDN-Loop
  // request header.
  //
  // The default of 0 means a request can transit the CdnLoopFilter
  // once. A value of 1 means that a request can transit the
  // CdnLoopFilter twice and so on.
  uint32 max_allowed_occurrences = 2;
}
