[api-gateway]: Support http, https and www-http as AppProtocol in kubernetes' service

Fix #6560

Author: Krast76

internal/dag/accessors.go

@@ -108,15 +108,21 @@ func validateExternalName(svc *core_v1.Service, enableExternalNameSvc bool) erro
 
 // the ServicePort's AppProtocol must be one of the these.
 const (
-	protoK8sH2C = "kubernetes.io/h2c"
-	protoK8sWS  = "kubernetes.io/ws"
+	protoK8sH2C  = "kubernetes.io/h2c"
+	protoK8sWS   = "kubernetes.io/ws"
+	protoHttp    = "www-http"
+	protoHttps   = "https"
+	protoWebHttp = "http"
 )
 
 func toContourProtocol(appProtocol string) (string, bool) {
 	proto, ok := map[string]string{
 		// *NOTE: for gateway-api: the websocket is enabled by default
-		protoK8sWS:  "",
-		protoK8sH2C: "h2c",
+		protoK8sWS:   "",
+		protoK8sH2C:  "h2c",
+		protoHttp:    "",
+		protoHttps:   "tls",
+		protoWebHttp: "",
 	}[appProtocol]
 	return proto, ok
 }