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Signed-off-by: huabing zhao <[email protected]>

internal/xds/translator/httpfilters.go

@@ -49,6 +49,8 @@ func registerHTTPFilter(filter httpFilter) {
 // always se their own native per-route configuration.
 type httpFilter interface {
 	// patchHCM patches the HttpConnectionManager with the filter.
+	// Note: this method may be called multiple times for the same filter, please
+	// make sure to avoid duplicate additions of the same filter.
 	patchHCM(mgr *hcmv3.HttpConnectionManager, irListener *ir.HTTPListener) error
 
 	// patchRoute patches the provide Route with a filter's Route level configuration.