fix(conformance-test): HTTPRouteRewriteHost (#2596)

Author: AlinsRan

Makefile

@@ -52,7 +52,7 @@ GO_LDFLAGS ?= "-X=$(VERSYM)=$(VERSION) -X=$(GITSHASYM)=$(GITSHA) -X=$(BUILDOSSYM
 # gateway-api
 GATEAY_API_VERSION ?= v1.3.0
 ## https://github.com/kubernetes-sigs/gateway-api/blob/v1.3.0/pkg/features/httproute.go
-SUPPORTED_EXTENDED_FEATURES = "HTTPRouteDestinationPortMatching,HTTPRouteMethodMatching,HTTPRoutePortRedirect,HTTPRouteRequestMirror,HTTPRouteSchemeRedirect,GatewayAddressEmpty,HTTPRouteResponseHeaderModification,GatewayPort8080"
+SUPPORTED_EXTENDED_FEATURES = "HTTPRouteDestinationPortMatching,HTTPRouteMethodMatching,HTTPRoutePortRedirect,HTTPRouteRequestMirror,HTTPRouteSchemeRedirect,GatewayAddressEmpty,HTTPRouteResponseHeaderModification,GatewayPort8080,HTTPRouteHostRewrite"
 CONFORMANCE_TEST_REPORT_OUTPUT ?= $(DIR)/apisix-ingress-controller-conformance-report.yaml
 ## https://github.com/kubernetes-sigs/gateway-api/blob/v1.3.0/conformance/utils/suite/profiles.go
 CONFORMANCE_PROFILES ?= GATEWAY-HTTP,GATEWAY-GRPC

internal/adc/translator/httproute.go

@@ -179,17 +179,19 @@ func (t *Translator) fillPluginFromHTTPRequestHeaderFilter(plugins adctypes.Plug
 	obj := plugins[pluginName]
 	var plugin *adctypes.RewriteConfig
 	if obj == nil {
-		plugin = &adctypes.RewriteConfig{
-			Headers: &adctypes.Headers{
-				Add:    make(map[string]string, len(reqHeaderModifier.Add)),
-				Set:    make(map[string]string, len(reqHeaderModifier.Set)),
-				Remove: make([]string, 0, len(reqHeaderModifier.Remove)),
-			},
-		}
+		plugin = &adctypes.RewriteConfig{}
 		plugins[pluginName] = plugin
 	} else {
 		plugin = obj.(*adctypes.RewriteConfig)
 	}
+	if plugin.Headers == nil {
+		plugin.Headers = &adctypes.Headers{
+			Add:    make(map[string]string, len(reqHeaderModifier.Add)),
+			Set:    make(map[string]string, len(reqHeaderModifier.Set)),
+			Remove: make([]string, 0, len(reqHeaderModifier.Remove)),
+		}
+	}
+
 	for _, header := range reqHeaderModifier.Add {
 		val := plugin.Headers.Add[string(header.Name)]
 		if val != "" {