improve dummy check and in scripts

check

@@ -1,6 +1,20 @@
 #!/bin/sh
 
-exec 3>&1
-exec 1>&2
+set -e
 
-echo "[]" >&3
+exec 3>&1 # make stdout available as fd 3 for the result
+exec 1>&2 # redirect all output to stderr for logging
+
+PAYLOAD=$(mktemp /tmp/resource-check.XXXXXX)
+
+cat > "$PAYLOAD" <&0
+
+TS=$(jq '.version.timestamp // empty' < "$PAYLOAD")
+
+if [ -z "$TS" ]; then
+  echo '[]' >&3
+else
+  jq -n "[
+    { timestamp: $TS }
+  ]" >&3
+fi