feat: prune old cld backups after sync

hosts/AZ-CLD-1/services/var-backup-sync.nix

@@ -27,6 +27,7 @@ in {
 
     path = with pkgs; [
       coreutils
+      findutils
       openssh
       rsync
       util-linux
@@ -53,7 +54,9 @@ in {
         exit 1
       fi
 
-      flock -n "$lock_file" \
+      (
+        flock -n 9
+
         rsync \
           -aH \
           --no-owner \
@@ -69,6 +72,13 @@ in {
           -e "ssh -i ${sshKey} -p ${targetPort} -o IdentitiesOnly=yes -o BatchMode=yes -o StrictHostKeyChecking=accept-new -o UserKnownHostsFile=/var/lib/${serviceName}/known_hosts" \
           ${sourceDir} \
           ${targetUser}@${targetHost}:${targetDir}
+
+        echo "Removing /var/backup files older than 7 days"
+        find ${sourceDir} -type f -mtime +7 -print -delete
+
+        echo "Removing empty directories under /var/backup"
+        find ${sourceDir} -mindepth 1 -depth -type d -empty -print -delete
+      ) 9>"$lock_file"
     '';
   };