Help me triage

[Daniel P. Berrange]

On Tue, Sep 30, 2008 at 09:04:38PM +0100, Keith Roberts wrote:
> On Tue, 30 Sep 2008, Peter Robinson wrote:
> 
> >To: Keith Roberts <keith at karsites.net>,
> >    For testers of Fedora Core development releases
> >    <fedora-test-list at redhat.com>
> >From: Peter Robinson <pbrobinson at gmail.com>
> >Subject: Re: Help me triage
> >
> >>>>># Is there a general policy around using perl in pre/post ?
> >>>>>https://bugzilla.redhat.com/show_bug.cgi?id=462996
> >>>>
> >>>>There is no such policy.
> >>>
> >>>I wish there was a policy for not using perl in pre/post scripts. The
> >>>number of packages that use perl in a single line of the spec file and
> >>>don't require it as a general dependency hence pulling in all of perl
> >>>for nothing.
> >>
> >>Not been following this topic that closely. Are you referring to using 
> >>perl
> >>for pre/post RPM package installation?
> >
> >Yes. As per the RHBZ bug that's mentioned (and just been closed
> >because the perl script has been replaced with a sed script).
> >
> >Peter
> 
> Would it be practical to use a PHP CLI script for pre/post 
> RPM installation - not in this particular case, but in 
> general? I find that bash scripts are a bit cryptic, and 
> lack the power that PHP CLI scripts can offer. I have 
> written backup scripts using PHP CLI mode scripts, and then 
> called bash O/S shell programs that are not natively 
> suppoerted by PHP. This gives me all the power of bash shell 
> scripting, and all the added functionality and ease of use 
> of PHP syntax :)

This is totally missing the point. The fact that RPM %post scripts
exist at all is bad enough, but if you find yourself needing more
"power" than just shell its usually a sign that you're solving the
wrong problem.  PHP isn't helping here - in fact it would be
encouraging over-use of scripts. It is a pretty reasonable generalization
that if you need more than shell, then you're probably doing it wrong.
Furthermore anything you do in %post, needs to be reversable upon
uninstall for %postun when the last instance of a package is removed.
If your script is longer than a couple of lines of shell, then its
highly unlikely you'll be able to create a bug-free %postun to
reverse its action.

Daniel
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