uhv: define extensible validation API #19752
Description
As part of the unified header validation component, Envoy will need to define an extensible API. The tech spec describes a simple API that will be initially implemented.
class HeaderValidator {
enum class HeaderEntryValidationResult { Accept, Reject };
virtual HeaderEntryValidationResult validateHeaderEntry(
const HeaderEntry& entry) PURE;
// validateRequestHeaderMap performs URI path normalization and may redirect
// request to the new URI path
enum class RequestHeaderMapValidationResult { Accept, Reject, Redirect };
virtual RequestHeaderMapValidationResult validateRequestHeaderMap(
RequestHeaderMap& header_map) PURE;
enum class ResponseHeaderMapValidationResult { Accept, Reject };
virtual ResponseHeaderMapValidationResult validateResponseHeaderMap(
ResponseHeaderMap& header_map) PURE;
};
class HeaderValidatorFactory : public Config::TypedFactory {
enum class Protocol { HTTP09, HTTP1, HTTP2, HTTP3 };
virtual std::shared_ptr<HeaderValidator> createHeaderValidator(
Protocol protocol) const PURE;
};The goal of this issue is to define the API, get feedback from the team and community, document the API, and potentially create factory stubs for the support HTTP codecs.