caddy-frontend: Fix configuration validation script

As caddy_configuration_state provides information with exit code use it
directly in the if instead of running it with $(), which stops execution when
configuration is not changed.

Improve checking for too old result - do not remove the file, instead check
for too old result and then recalculate.

/reviewed-on nexedi/slapos!589

software/caddy-frontend/buildout.hash.cfg

@@ -98,7 +98,7 @@ md5sum = 061cc244558fd3af2b6bacf17cae5555
 
 [template-validate-script]
 filename = templates/validate-script.sh.in
-md5sum = 89839a3f4ab71cab459afd1c27d00326
+md5sum = f26e11574f266c7437c9c89e3c93825a
 
 [template-configuration-state-script]
 filename = templates/configuration-state-script.sh.in

software/caddy-frontend/templates/validate-script.sh.in

@@ -5,9 +5,12 @@ set -e
 LAST_STATE_FILE={{ last_state_file }}
 
 # force validation each 2 hours
-[ -f $LAST_STATE_FILE ] && find $LAST_STATE_FILE -mmin +120 -delete
-configuration_state=$({{ caddy_configuration_state }})
-if [ ! -f $LAST_STATE_FILE ] || $configuration_state ; then
+old_found=1
+if [ -f $LAST_STATE_FILE ] ; then
+  old_found=$(find $LAST_STATE_FILE -mmin +120 | wc -l)
+fi
+
+if [ "$old_found" -eq 1 ] || {{ caddy_configuration_state }} ; then
   # do not catch errors during validation
   set +e
   {{ wrapper }} -validate