Let pdebuild update build ev

[Werner Mahr]

Junichi Uekawa wrote:

> At Wed, 12 Sep 2012 05:46:35 +0200,
> Werner Mahr wrote:
>> 
>> Am Dienstag, 11. September 2012, 10:49:25 schrieben Sie:
>> > hmm.. I don't see this is useful ?
>> 
>> In my situtation it is usefull. I have stable, testing, natty and oneiric
>> machines for amd64 and i386. I could use hooks to update them when they
>> get used, but in that way the update wouldn't be saved (in qemubuilder
>> the items wouldn't even be cached). If I update them in a row, I can use
>> the caching of my proxy to save some time, but then I would have to find
>> out in my script if I would have to call qemubuilder or pbuilder.
>> 
>> Otoh when I build from cmdline, I don't need to update everytime when I
>> build something, so I have a command to call only one command and I'm
>> done, instead of going everytime trough an update, which would be the
>> case with a hook (I'm not sure if there is a cmdlineoption to let the
>> builder do it everytime it is called, but erverytime is to often).
>> 
>> I have an i386 machine, so at least in qemubuilder I really like to save
>> every command I can save, as it's much slower than a real machine.
> 
> Personally I use a wrapper script that does the following (update the
> chroot if it's older than 1 day), you probably want something in the
> line. apt-get update etc are slow so you'll probably want to avoid
> running it every time.
> 
>[script cut]

[Resent to here for completeness]

Yeah, a script for that could be usefull if you want to update them all. In 
my 
case I have a script that build's new svn revisions of amule, when they 
appear. If I would use something like your wrapper, I would either have to 
run 
it from a cronjob, or would have to run it in the script right. If run in a 
cronjob, I update stuff that's not used for sometimes 2 weeks or more. If 
run 
in the script, I could run the snippet right before the build, so at least 4 
machines get updated when one is startetd, or I could run it a the beginning 
of the script, which could mean that the last machine is started after the 
archives have been updated again. In started this update mechanism, because 
I 
got build failures from uninstallable deps. They just have been updated and 
the old version hasn't been found for downloading.

With a wrapper script I would have to find out the correct baseimgae and 
update 
only this one, plus I have to find out which system to use, as the i386 
builds 
are done with pbuilder. This are all informations pdebuild already has, but 
doesn't tell me, so in sum I would duplicate the functions of pdebuild in a 
wrapper where I could just use these functions. And from a logical point of 
view: I installed pdebuild to just call one command for building different 
packages on different arches and distros, and I don't need to implement any 
decisions which program to use. If I would have to implement this functions 
for the update of the base-images, I could just use the result of this 
decisions and call the different programs directly, which would render 
pdebuild 
useless.