report which backup tasks are missing in the xymon report

ROOT/DEBIAN/control

@@ -3,6 +3,6 @@ Priority: optional
 Section: otherosfs
 Maintainer: Chemistry COs <support@ch.cam.ac.uk>
 Architecture: all
-Version: 0.9-ch101
+Version: 0.9-ch102
 Depends: zfs-dkms, postgresql-13 | postgresql-9.5 | postgresql-9.4 , liblockfile-simple-perl, libdbi-perl, libjson-perl, libzfs-perl-chem, libnet-openssh-perl, libdbd-pg-perl, mbuffer, rsync, nfs-kernel-server, pv, libwww-curl-perl, libformat-human-bytes-perl
 Description: a backup system using ZFS (repository 'backup-scheduler')

ROOT/usr/lib/xymon/client/ext/zfs-backups

@@ -57,6 +57,11 @@ my $stj=$dbh->prepare($sqlc);
 my $backuptask_count_query = "select count(backup_task_id) from backup_task natural join host where hostname=?";
 my $backtask_count=$dbh->prepare($backuptask_count_query);
 
+# if a task has never completed, it will be missing from hobbit_view. We identify this via a full join
+# on the view and look for a null field.
+my $missing_tasks_query = "select backup_task_id, backup_task.backup_task_name from backup_task natural join host full join hobbit_view using (backup_task_id) where host.hostname=? and hobbit_view.backup_task_name is null";
+my $missing_tasks = $dbh->prepare($missing_tasks_query);
+
 foreach my $hr (@{$all}) {
     my $hostname=$hr->[0];
     print "Considering $hostname\n";
@@ -209,6 +214,11 @@ foreach my $hr (@{$all}) {
     if($rows_for_this_host != $required_rows_for_this_host) {
       my $msg = "$rows_for_this_host results logged for host but $required_rows_for_this_host backup tasks are configured. Check backup_log table: maybe there has not yet been a succesful backup?\n";
       $bb->color_line('red', $msg);
+
+      $missing_tasks->execute($hostname);
+      while(my $missing_task = $missing_tasks->fetchrow_hashref) {
+         $bb->color_line('red', "missing backup for task id " . $missing_task->{'backup_task_id'} . " (" . $missing_task->{'backup_task_name'} . ")\n");
+      }
     }
     $bb->send;
 }