Systemd conversion versus updates in back Fedora branches

[Richard Shaw]

On Sun, Oct 23, 2011 at 10:52 PM, Tom Lane <tgl at redhat.com> wrote:
> The current packaging guidelines require packages that update from sysv
> init scripts to systemd scripts to provide conversion triggers that are
> fired on the basis of an NVR comparison:
> https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Packages_migrating_to_a_systemd_unit_file_from_a_SysV_initscript
>
> That is, we assume that we know that all releases with NVR < some-cutoff
> use initscripts and all releases with NVR >= same-cutoff use systemd.
> The comments in the above-linked page acknowledge that this means it's
> impossible to upgrade the package to a newer upstream release in
> pre-systemd Fedora branches.  (You can't just move the cutoff value
> forward, because then an upgrade in F16 or later will mistakenly re-fire
> the update trigger.)

I'm not sure if this was the best things to do but on the mythtv
package on RPM Fusion I added an additional requirement for
%triggerrun that the fedora release >= 16 by enclosing the whole
scriptlet in a %if 0{?fedora}...%endif,  which seemed to make sense as
we're not supposed to change/convert within a release. I had to do
this because the same EVR is used for all supported Fedora releases.

Is there something wrong with this approach?

Thanks,
Richard