Re: RFC: add maximum debootstrap storing time, or check for updates and invalidate

[Jan Kiszka <jan.kiszka@siemens.com>]

On 04.11.21 16:12, Henning Schild wrote:
> Hi,
> 
> Isar does have the problem that a debootstrap does the only real
> "apt-get update". That is in fact intentional but can lead to the
> situation where an outdated chrootfs can break a build. I.e. apt-get
> wants to install a package in a version that is not available upstream
> anymore.
> 
> Now when this happens is impossible to say. It depends on the amount of
> packages one has, maybe the distro one is using (sid moving faster than
> oldstable), and frozen custom mirror never moving.
> 
> With local builds people usually clean all, and for sstate people will
> also have to find their own way of dealing with it. But one could say
> ... it is becoming more of a problem. Not something to not merge the
> sstate changes for, but something to think about for the future. 
> 
> My current idea would be to introduce
> DISTRO_MAX_CHROOT_AGE?="3d"
> 
> anon python function
>   if /var/..apt/ older than DISTRO_MAX_AGE
>     cleanall bootstrap recipe, or somehow enforce re-run
> 
> An alternative (maybe better) would be to say
> 
> check_for_updates after rootfs_install
>   copy rootfs to rootfs_tmp
>   chroot rootfs_tmp
>   apt-get update
>   if "apt-get upgrade is not empty"
>     bbwarn(image lacking some updates that meanwhile have been
>     published)
>     cleanall bootstrap recipe
>     if ISAR_BE_STRICT_ABOUT_THAT=true
>       fail
> 

It's all a trade-off: The above will only run when redoing a rootfs, not
when the buildchroot is considered "done" while a dependency
installation later on may still fail. And running such a check on every
rebuild, even when you only want to build a single package, not a
complete image, may take too much time.

I agree that some update check could be valuable, provided its
controllable whether it is executed or not. And bonus for a simpler way
of triggering the invalidation of all bootstrap tasks, faster than "rm
-rf tmp".

Jan

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