robustness against empty mirror var

diff --git a/vars/buildcontainer.groovy b/vars/buildcontainer.groovy
index e37145036072275d7787cad1258db56f9e5c65be..643cec461900ee3fa2ed9a1ffdcda2b0eecd5d68 100644 (file)
--- a/vars/buildcontainer.groovy
+++ b/vars/buildcontainer.groovy
@@ -25,7 +25,7 @@ def call(Map args) {
 
   mirrorArg = ""
   if (args.mirror) {
-    mirrorArg = "--registry-mirror ${mirrorArg}"
+    mirrorArg = "--registry-mirror '${mirrorArg}'"
   }
   container('kaniko') { 
     sh """