[pkg-go] Bug#1060297: acmetool's systemd timer is stopped when the package is upgraded

[Timothy Allen]

This happened to me again today. Having learned a little more about 
Debian packaging, I looked at the flowchart of the upgrade process[1] 
and the maintainer scripts executed. The file 
/var/lib/dpkg/info/acmetool.preinst contains the following code:

    # Automatically added by dh_installsystemd/13.24.2
    if [ -z "$DPKG_ROOT" ] && [ "$1" = upgrade ] && [ -d
    /run/systemd/system ] ; then
             deb-systemd-invoke stop 'acmetool.timer' >/dev/null || true
    fi
    # End automatically added section

...which would explain why the timer gets stopped on upgrade. 
Unfortunately, I can't find "deb-systemd-invoke stop" in debhelper's 
source in the context of a preinst script[2], nor can I find any 
reference to a preinst script in the acmetool packaging[3], so I'm at a 
loss to explain where that code comes from.

It occurs to me that the above code would be fine if the postinst script 
restarted the timer afterwards. Looking at acmetool's control file, I 
see it calls:

    dh_installsystemd --no-enable --no-start acmetool.timer

...where "--no-start" is described as:

    Do not start the unit file after upgrades and after initial
    installation (the
    latter is only relevant for services without a corresponding init
    script).

I can understand not wanting to start the timer after initial 
installation (it doesn't have a valid configuration, so it'll probably 
just produce errors if started), but given that Let's Encrypt is 
shortening certificate times to 47 days[4], and no longer sending 
reminder emails when certificates are about to expire[5], having 
acmetool upgrades silently stop certificate renewals is pretty annoying.

Perhaps "--no-stop-on-upgrade" could be added to the dh_installsystemd 
invocation? Since acmetool isn't a long-lived service, restarting it 
automatically on upgrade isn't necessary, it'll restart itself  anyway.


Timothy.


[1]: https://www.debian.org/doc/debian-policy/ap-flowcharts.html

[2]: 
https://github.com/search?q=repo%3ADebian%2Fdebhelper%20deb-systemd-invoke%20stop&type=code

[3]: 
https://salsa.debian.org/search?search=preinst&nav_source=navbar&project_id=6891&group_id=2638&search_code=true&repository_ref=master

[4]: https://www.theregister.com/2025/04/14/ssl_tls_certificates/

[5]: https://letsencrypt.org/2025/01/22/ending-expiration-emails/