Line data    Source code

       1             : #pragma once
       2             : 
       3             : #include <string>
       4             : #include <vector>
       5             : 
       6             : #include "envoy/access_log/access_log.h"
       7             : #include "envoy/config/core/v3/base.pb.h"
       8             : #include "envoy/http/header_evaluator.h"
       9             : #include "envoy/http/header_map.h"
      10             : 
      11             : #include "source/common/http/header_map_impl.h"
      12             : #include "source/common/protobuf/protobuf.h"
      13             : 
      14             : namespace Envoy {
      15             : namespace Router {
      16             : 
      17             : class HeaderParser;
      18             : using HeaderParserPtr = std::unique_ptr<HeaderParser>;
      19             : 
      20             : using HeaderAppendAction = envoy::config::core::v3::HeaderValueOption::HeaderAppendAction;
      21             : using HeaderValueOption = envoy::config::core::v3::HeaderValueOption;
      22             : using HeaderValue = envoy::config::core::v3::HeaderValue;
      23             : 
      24             : struct HeadersToAddEntry {
      25             :   HeadersToAddEntry(const HeaderValue& header_value, HeaderAppendAction append_action);
      26             :   HeadersToAddEntry(const HeaderValueOption& header_value_option);
      27             : 
      28             :   std::string original_value_;
      29             :   bool add_if_empty_ = false;
      30             : 
      31             :   Formatter::FormatterPtr formatter_;
      32             :   HeaderAppendAction append_action_;
      33             : };
      34             : 
      35             : /**
      36             :  * HeaderParser manipulates Http::HeaderMap instances. Headers to be added are pre-parsed to select
      37             :  * between a constant value implementation and a dynamic value implementation based on
      38             :  * StreamInfo::StreamInfo fields.
      39             :  */
      40             : class HeaderParser : public Http::HeaderEvaluator {
      41             : public:
      42             :   /*
      43             :    * @param headers_to_add defines the headers to add during calls to evaluateHeaders
      44             :    * @return HeaderParserPtr a configured HeaderParserPtr
      45             :    */
      46             :   static HeaderParserPtr
      47             :   configure(const Protobuf::RepeatedPtrField<HeaderValueOption>& headers_to_add);
      48             : 
      49             :   /*
      50             :    * @param headers_to_add defines headers to add during calls to evaluateHeaders.
      51             :    * @param append_action defines action taken to append/overwrite the given value for an existing
      52             :    * header or to only add this header if it's absent.
      53             :    * @return HeaderParserPtr a configured HeaderParserPtr.
      54             :    */
      55             :   static HeaderParserPtr
      56             :   configure(const Protobuf::RepeatedPtrField<envoy::config::core::v3::HeaderValue>& headers_to_add,
      57             :             HeaderAppendAction append_action);
      58             : 
      59             :   /*
      60             :    * @param headers_to_add defines headers to add during calls to evaluateHeaders
      61             :    * @param headers_to_remove defines headers to remove during calls to evaluateHeaders
      62             :    * @return HeaderParserPtr a configured HeaderParserPtr
      63             :    */
      64             :   static HeaderParserPtr
      65             :   configure(const Protobuf::RepeatedPtrField<HeaderValueOption>& headers_to_add,
      66             :             const Protobuf::RepeatedPtrField<std::string>& headers_to_remove);
      67             : 
      68        1386 :   static const HeaderParser& defaultParser() {
      69        1386 :     static HeaderParser* instance = new HeaderParser();
      70        1386 :     return *instance;
      71        1386 :   }
      72             : 
      73             :   void evaluateHeaders(Http::HeaderMap& headers, const Formatter::HttpFormatterContext& context,
      74             :                        const StreamInfo::StreamInfo& stream_info) const override;
      75             : 
      76             :   void evaluateHeaders(Http::HeaderMap& headers, const Formatter::HttpFormatterContext& context,
      77             :                        const StreamInfo::StreamInfo* stream_info) const;
      78             : 
      79             :   /**
      80             :    * Helper methods to evaluate methods without explicitly passing request and response headers.
      81             :    * The method will try to fetch request headers from steam_info. Response headers will always be
      82             :    * empty.
      83             :    */
      84         648 :   void evaluateHeaders(Http::HeaderMap& headers, const StreamInfo::StreamInfo& stream_info) const {
      85         648 :     evaluateHeaders(headers, {stream_info.getRequestHeaders()}, &stream_info);
      86         648 :   }
      87          70 :   void evaluateHeaders(Http::HeaderMap& headers, const StreamInfo::StreamInfo* stream_info) const {
      88          70 :     evaluateHeaders(headers,
      89          70 :                     Formatter::HttpFormatterContext{
      90          70 :                         stream_info == nullptr ? nullptr : stream_info->getRequestHeaders()},
      91          70 :                     stream_info);
      92          70 :   }
      93             : 
      94             :   /*
      95             :    * Same as evaluateHeaders, but returns the modifications that would have been made rather than
      96             :    * modifying an existing HeaderMap.
      97             :    * @param stream_info contains additional information about the request.
      98             :    * @param do_formatting whether or not to evaluate configured transformations; if false, returns
      99             :    * original values instead.
     100             :    */
     101             :   Http::HeaderTransforms getHeaderTransforms(const StreamInfo::StreamInfo& stream_info,
     102             :                                              bool do_formatting = true) const;
     103             : 
     104             :   static std::string translateMetadataFormat(const std::string& header_value);
     105             :   static std::string translatePerRequestState(const std::string& header_value);
     106             : 
     107             : protected:
     108         428 :   HeaderParser() = default;
     109             : 
     110             : private:
     111             :   std::vector<std::pair<Http::LowerCaseString, HeadersToAddEntry>> headers_to_add_;
     112             :   std::vector<Http::LowerCaseString> headers_to_remove_;
     113             : };
     114             : 
     115             : } // namespace Router
     116             : } // namespace Envoy