fix(k8s): validate Mathmast username input and enhance error handling in kubectl config clearing

Signed-off-by: 孙振宇 <>

bin/freeleaps-cluster-authenticator

@@ -186,7 +186,15 @@ setup_kubelogin() {
 
 prompt_username() {
   echo "[PROMPT] Please enter your Mathmast account name (ending with @mathmast.com, eg. jack@mathmast.com):"
+  
   read -r username
+
+  # While loop to check if username is valid
+  while ! echo "${username}" | grep -qE '^[a-zA-Z0-9._%+-]+@mathmast.com$'; do
+    echo "[ERROR] Username invalid, please enter a valid Mathmast account name (ending with @mathmast.com, eg. jack@mathmast.com):"
+    read -r username
+  done
+
   echo "[PROMPT] Username: ${username}"
 }
 
@@ -260,10 +268,25 @@ clear_auth() {
 
   echo "[CLEAR] Clearing kubectl authentication..."
 
-  kubectl config delete-user "${username}"
-  kubectl config delete-context "${username}@freeleaps-cluster"
-  kubectl config delete-cluster freeleaps-cluster
-  kubectl config unset current-context
+  if ! kubectl config delete-user "${username}" > /dev/null 2>&1; then
+    echo "[ERROR] User ${username} not found in kubectl config."
+    exit 1
+  fi
+
+  if ! kubectl config delete-context "${username}@freeleaps-cluster" > /dev/null 2>&1; then
+    echo "[ERROR] Context ${username}@freeleaps-cluster not found in kubectl config."
+    exit 1
+  fi
+
+  if ! kubectl config delete-cluster freeleaps-cluster > /dev/null 2>&1; then
+    echo "[ERROR] Cluster freeleaps-cluster not found in kubectl config."
+    exit 1
+  fi
+
+  if ! kubectl config unset current-context > /dev/null 2>&1; then
+    echo "[ERROR] Unable to unset current context in kubectl config."
+    exit 1
+  fi
 
   echo "[CLEAR] kubectl authentication cleared successfully."
 }