RE: [OE-core] [PATCH] scripts/oe-setup-builddir: migrate build/conf/templateconf.cfg to new template locations

[Peter Kjellerstedt <peter.kjellerstedt@axis.com>]

> -----Original Message-----
> From: Alexander Kanavin <alex.kanavin@gmail.com>
> Sent: den 2 september 2022 17:09
> To: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
> Cc: openembedded-core@lists.openembedded.org; Alexander Kanavin
> <alex@linutronix.de>
> Subject: Re: [OE-core] [PATCH] scripts/oe-setup-builddir: migrate
> build/conf/templateconf.cfg to new template locations
> 
> On Fri, 2 Sept 2022 at 16:47, Peter Kjellerstedt
> <peter.kjellerstedt@axis.com> wrote:
> 
> > The expectation is of course that if one has one's own .templateconf
> > file, then it will of course have to be updated to match the changes
> > in OE. Nothing unusual with that. But that is something I do as
> > maintainer of our environment. For our developers it will then just
> > work.
> 
> Please consider that there are three different ways to obtain the
> location of the template, and they must all work. For those who have
> created a build/conf by supplying TEMPLATECONF on the command line or
> templateconf.cfg (which I would say is everyone, except you) the
> suggested code will only make things worse, not better. It would take
> wrong but helpful value in templateconf.cfg that points to a custom
> template, and replace it with meta/conf/templates/default, because
> that is what they have in .templateconf. Then all trace of where the
> template came from is lost.

Actually, that does not correspond to what the documentation says. 
The way we do things (i.e., modify .templateconf to define a default 
TEMPLATECONF) _is_ what the documentation says one should do. See:
https://docs.yoctoproject.org/dev/singleindex.html#creating-a-custom-template-configuration-directory

Also note that templateconf.cfg is not documented at all. My guess 
(based on the current code) is that it is only supposed to be used 
internally as a way to store the value of a previous build where 
TEMPLATECONF was explicitly set.

So based on the documentation, the officially supported ways to 
configure the template directory is to either specify TEMPLATECONF 
explicitly or by modifying .templateconf to set a default value.

That said, I do agree with your suggested change to prefer an 
explicitly set TEMPLATECONF before a value from templateconf.cfg, 
which also agrees with the idea that templateconf.cfg is only an 
internal way of storing the last TEMPLATECONF used.

> 
> And as discussed previously, you don't even need to jump through the
> extra hoops with generated template configurations to begin with, and
> can write the dynamically generated configs directly into build/conf.
> 
> Alex

//Peter