[Zope3-dev] Building standalone ZPT from Zope 3 using zpkgtools

[Martijn Faassen]

Shane Hathaway wrote:
[snip]
> I'm sure Fred is doing excellent work, but I'm having trouble seeing why
> we need zpkgtools.  Is it not sufficient to just "python setup.py
> install" all of Zope 3?  I've been doing that with Zope 3 Subversion
> checkouts and Twisted, even though I actually use less than 10% of the
> code installed.  In fact, my co-workers are about to put such a system
> into production.  The unused code causes no problems that I've detected.

I think one of the main reasons for zpkgtools is indeed to allow a 
release of part of the repository, such as just the page template 
engine, but as you say, in the context of Five I've definitely found it 
a lot easier to just tell people to use the whole of Zope 3, as that is 
already released by another party. I also think it easier to have the 
release and repository be very similar.

I'm not convinced myself that this weighs up against the reasons not to 
invent a zope3 specific packaging system; there are a few drawbacks 
currently:

* it's unique to Zope 3 and ZODB. Nobody else is using it. Is the Zope 3 
project in the business of building package tools, or do we not have 
enough difficulty on our hands just building Zope 3?

* apparently, as seen on the ZODB list, the packaging format currently 
used makes life harder for downstream packages such as debian.

* it doesn't tackle some use cases. I'm not sure it could help 
integration of Zope 3 into Zope 2.8, for instance; a svn:external seemed 
to make more sense.

I think the first point is the most important worry; we're doing 
something nobody else is doing in an area outside Zope's core purpose, 
which is to be a web application service. This stands apart from the 
quality and merit the tool and its ideas certainly have. I just do not 
think it a good idea if the Zope project ends up having to maintain 
*and* explain this indefinitely. I hope, and trust this is the 
intention, that efforts can be undertaken to make the packaging tool 
used outside of the Zope project, preferably a Python standard. Of 
course you still run the significant risk it will never be accepted as such.

Regards,

Martijn