[ome-users] E-mailing users on the system, Cron jobs and backing up,

[josh.moore at gmx.de]

Woodbridge, Mark R writes:
 > > -----Original Message-----
 > > Sent: 11 August 2009 14:51
 > > To: ome-users
 > > Subject: [ome-users] E-mailing users on the system, Cron jobs and
 > > backing up,

 > > 1/ Is there an easy way of extracting users e-mail addresses from
 > > omero to send then an e-mail, (for example to warn about a
 > > shutdown or maintenance) I would ideally only wish to e-mail
 > > active users, ie people who have used omero in the last month for
 > > example. Clearly I can copy and paste out the addresses at the
 > > moment, but as more users are added to the system this will ot be
 > > practical.
 > 
 > I run this command (on Linux) which gives a list that I just copy
 > and paste into Outlook:
 > 
 > PGPASSWORD=<dbpassword> psql -h <dbserver> -p <dbport> -U <dbuser>
 > -c 'select email from experimenter' <dbname>

I added a ticket for this type of functionality, because at the moment
there's nothing like "getActiveUsers()":

  https://trac.openmicroscopy.org.uk/omero/ticket/1419

The information is stored in that database, so it's just a matter of
exposing it.

 > > 2/ I was wondering if anyone has a script that could be run as a
 > > cron job to make sure the omero server is running, and if its not
 > > running start it,
 > 
 > I have a cron job that runs a short Java program that tries to
 > connect to OMERO and sends me an email if it fails. I can send you
 > this off-list if it would help. It could be done even more simply
 > using bash and python. To actually check whether the server is
 > running (regardless of whether it is accepting connections) I guess
 > you'll have to use 'ps' or its equivalent on Windows (or perhaps
 > some ICE monitoring tool?)

There are various ways to do this, depending on what one wants to
guarantee.

 bin/omero admin status || bin/omero admin start

would do the most basic check and if it does not find the server,
start it. "start" will also run "status" until either 1) the server is
up or 2) 5 minutes pass.

"status", however, does not attempt a login which is definitely the
best way of fulling checking the system, and what I tend to use in my
cron jobs.

 > We host our OMERO database and files on our standard (file)servers
 > so do we don't do any OMERO-specific backups, but I have my doubts
 > about what happens if a transaction/upload is in progress when the
 > backup is made.

pg_dump is transactionally safe, but the files on disk may be out of
sync. A filesystem level backup is less safe from the postgres
perspective.

 > Mark.

~Josh.