S3: Add Vary header for non-wildcard AllowOrigin (#7547)

weed/s3api/cors/cors.go

@@ -361,6 +361,10 @@ func ApplyHeaders(w http.ResponseWriter, corsResp *CORSResponse) {
 
 	if corsResp.AllowOrigin != "" {
 		w.Header().Set("Access-Control-Allow-Origin", corsResp.AllowOrigin)
+
+		if corsResp.AllowOrigin != "*" {
+			w.Header().Add("Vary", "Origin")
+		}
 	}
 
 	if corsResp.AllowMethods != "" {