systemd unit files for backing up the mongo database of a standard rocket.chat docker install

mongo-backup.service

[Unit]
Description=Run a backup-dump of the mongo database in the mongo docker container
Requisite=mongo.service
After=mongo.service

[Service]
Type=oneshot
User=root
# have to escape the %s or systemd replaces them
ExecStart=/bin/docker exec -t mongo bash -c 'mongodump --archive=/data/dump/$(date +%%Y%%m%%d%%H%%M%%S).gz --gzip'

# notify #rocket-admin channel that the backup worked
# N.B. need to update the host and hook token in the URL part
ExecStartPost=/bin/bash -c 'curl --insecure --silent -X POST -H \'Content-Type: application/json\' --data \'{"text":"Backup to %H:/data/mongo/dump/ completed successfully"}\' https://HOST/hooks/WEBHOOKKEY | grep --quiet \'^{"success":true}$\''

# delete all but 14 most recent backups (double % for escaping systemd replacements)
ExecStartPost=/bin/bash -c "echo 'Mongo backup completed; removing excess backups..' ; find /data/mongo/dump/ -type f -printf '%%T@ %%p\n' | sort --reverse --numeric | tail --lines +14 | cut --fields 2 --delimiter=' ' | xargs --no-run-if-empty rm -fv"

mongo-backup.timer

[Unit]
Description=mongo backup timer

[Timer]
OnCalendar=daily

rocketchat.service (snippet)

[Unit]
Description=rocketchat
Requires=docker.service
Requires=httpd.service
Requires=mongo.service
Requires=mongo-backup.timer
After=docker.service
After=mongo.service

[Install]
WantedBy=multi-user.target

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