Better k9s alias

zsh/aliases.zsh

@@ -79,7 +79,20 @@ fi
 # Docker and kubernetes aliases
 command -v k9s > /dev/null 2>&1
 if [ $? -eq 0 ]; then
-    alias kns="k9s"
+    kns() {
+        local kube_config
+        if [ -z $KUBECONFIG ]; then
+            kube_config=$HOME/.kube/config
+        else
+            kube_config=$KUBECONFIG
+        fi
+        if [ -f $kube_config ]; then
+            k9s
+        else
+            echo >&2 error: $kube_config does not exist
+            return 1
+        fi
+    }
 fi
 
 command -v lazydocker > /dev/null 2>&1