Bug#991947: apt-setup: Consider adding $codename-updates configuration to /etc/apt/sources.list (if available even if yet $codename is testing)

[Salvatore Bonaccorso <carnil@debian.org>]

Source: apt-setup
Version: 1:0.166
Severity: wishlist
Tags: d-i
X-Debbugs-Cc: carnil@debian.org

Dear Debian Install System Team,

When installing bullseye with the current RC3 I noticed that while the
debconf menu suggests (and has selected) to add release updates suites
($codename-updates) to the sources.list in case when bullseye is yet
testing, they are not added via generators/92updates because
generators/90services-select in case of the suite not beeng stable or
odstable, does not select it:

updates=y
if [ "$suite" != stable ] && [ "$suite" != oldstable ]; then
        disable_service updates || true
        updates=n
fi

I wonder if this could be handled in times before a stable release is
planned, and the suite is already present on the mirrors (this is at
some time before a stable release prepartion when release team starts to
interact with infrastructure teams I think to setup what is needed for
the next stable release)

The reason I ask this, is that the coverage would be bigger for people
having it in the sources.list if they install it in time shortly before
a stable release is released, and we strongly rely on updates to be
possible to push via the stable-updates mechanism, see for instance
https://lists.debian.org/debian-stable-announce/2021/06/msg00001.html ?

Cyril mentioned two ideas how this can be done. Either having a flag
which can be enabled one we switch from an Alpha  to some RC Release for
d-i once the installer matured enough and infrastructure is set up in
perspective of a future stable release.

One other alternative would be to do an online test if the suite is
already present and only add it in that case.

What do you think of this idea? If you think it's nonsense, feel free to
mark it straight as wontfix and close it.

Regards,
Salvatore