Line data    Source code

       1             : #include "source/common/http/header_mutation.h"
       2             : 
       3             : #include "source/common/router/header_parser.h"
       4             : 
       5             : namespace Envoy {
       6             : namespace Http {
       7             : 
       8             : namespace {
       9             : 
      10             : using HeaderAppendAction = envoy::config::core::v3::HeaderValueOption::HeaderAppendAction;
      11             : using HeaderValueOption = envoy::config::core::v3::HeaderValueOption;
      12             : 
      13             : // TODO(wbpcode): Inherit from Envoy::Router::HeadersToAddEntry to make sure the formatter
      14             : // has the same behavior as the router's formatter. We should try to find a more clean way
      15             : // to reuse the formatter after the router's formatter is completely removed.
      16             : class AppendMutation : public HeaderEvaluator, public Envoy::Router::HeadersToAddEntry {
      17             : public:
      18             :   AppendMutation(const HeaderValueOption& header_value_option)
      19           0 :       : HeadersToAddEntry(header_value_option), header_name_(header_value_option.header().key()) {}
      20             : 
      21             :   void evaluateHeaders(Http::HeaderMap& headers, const Formatter::HttpFormatterContext& context,
      22           0 :                        const StreamInfo::StreamInfo& stream_info) const override {
      23           0 :     const std::string value = formatter_->formatWithContext(context, stream_info);
      24             : 
      25           0 :     if (!value.empty() || add_if_empty_) {
      26           0 :       switch (append_action_) {
      27           0 :         PANIC_ON_PROTO_ENUM_SENTINEL_VALUES;
      28           0 :       case HeaderValueOption::APPEND_IF_EXISTS_OR_ADD:
      29           0 :         headers.addReferenceKey(header_name_, value);
      30           0 :         return;
      31           0 :       case HeaderValueOption::ADD_IF_ABSENT: {
      32           0 :         auto header = headers.get(header_name_);
      33           0 :         if (!header.empty()) {
      34           0 :           return;
      35           0 :         }
      36           0 :         headers.addReferenceKey(header_name_, value);
      37           0 :         break;
      38           0 :       }
      39           0 :       case HeaderValueOption::OVERWRITE_IF_EXISTS:
      40           0 :         if (headers.get(header_name_).empty()) {
      41           0 :           return;
      42           0 :         }
      43           0 :         FALLTHRU;
      44           0 :       case HeaderValueOption::OVERWRITE_IF_EXISTS_OR_ADD:
      45           0 :         headers.setReferenceKey(header_name_, value);
      46           0 :         break;
      47           0 :       }
      48           0 :     }
      49           0 :   }
      50             : 
      51             : private:
      52             :   Envoy::Http::LowerCaseString header_name_;
      53             : };
      54             : 
      55             : class RemoveMutation : public HeaderEvaluator {
      56             : public:
      57           0 :   RemoveMutation(const std::string& header_name) : header_name_(header_name) {}
      58             : 
      59             :   void evaluateHeaders(Http::HeaderMap& headers, const Formatter::HttpFormatterContext&,
      60           0 :                        const StreamInfo::StreamInfo&) const override {
      61           0 :     headers.remove(header_name_);
      62           0 :   }
      63             : 
      64             : private:
      65             :   const Envoy::Http::LowerCaseString header_name_;
      66             : };
      67             : } // namespace
      68             : 
      69           0 : HeaderMutations::HeaderMutations(const ProtoHeaderMutatons& header_mutations) {
      70           0 :   for (const auto& mutation : header_mutations) {
      71           0 :     switch (mutation.action_case()) {
      72           0 :     case envoy::config::common::mutation_rules::v3::HeaderMutation::ActionCase::kAppend:
      73           0 :       header_mutations_.emplace_back(std::make_unique<AppendMutation>(mutation.append()));
      74           0 :       break;
      75           0 :     case envoy::config::common::mutation_rules::v3::HeaderMutation::ActionCase::kRemove:
      76           0 :       header_mutations_.emplace_back(std::make_unique<RemoveMutation>(mutation.remove()));
      77           0 :       break;
      78           0 :     default:
      79           0 :       PANIC_DUE_TO_PROTO_UNSET;
      80           0 :     }
      81           0 :   }
      82           0 : }
      83             : 
      84             : void HeaderMutations::evaluateHeaders(Http::HeaderMap& headers,
      85             :                                       const Formatter::HttpFormatterContext& context,
      86           0 :                                       const StreamInfo::StreamInfo& stream_info) const {
      87           0 :   for (const auto& mutation : header_mutations_) {
      88           0 :     mutation->evaluateHeaders(headers, context, stream_info);
      89           0 :   }
      90           0 : }
      91             : 
      92             : } // namespace Http
      93             : } // namespace Envoy