[Zope3-Users] Re: Using svn checkout with zc packages

[Philipp von Weitershausen]

On 29 Jul 2007, at 23:27 , Tom Dossis wrote:
>> P.S.: I can't recommend easy_install because that will install  
>> eggs into the global site-packages location (which is rarely a  
>> good idea when you're deploying Zope). Unless of course you use  
>> workingenv or virtual python.
>
> You can configure the easy_install target location(s) easily enough:
>
> http://peak.telecommunity.com/DevCenter/EasyInstall#configuration- 
> files
> http://peak.telecommunity.com/DevCenter/EasyInstall#custom- 
> installation-locations
> http://docs.python.org/inst/config-syntax.html
>
> For example I use the file ~/.pydistutils.cfg to install all eggs  
> to my 'personal' location:
> (see: http://peak.telecommunity.com/DevCenter/EasyInstall#mac-os-x- 
> user-installation).
>
> [install]
> install_lib = ~/Library/Python/$py_version_short/site-packages
> install_scripts = ~/bin
>
> Are there shortcomings using these options?

For me, the whole point of *not* installing Zope into site-packages  
is isolation. I have many different sandboxes that I don't want to  
interfere with each other (just like in the old days, I could have  
multiple Zope installations and instances of those installations that  
didn't know anything of each other).

Sure, I can use .pydistutils.cfg to set an alternate location, but  
that'll apply for *all* sandboxes again, therefore not serving the  
isolation concern. And yes, I can tell easy_install on a one-by-one  
basis where I want to install my eggs, but that's not really  
comfortable (also, the destination has to be on your PYTHONPATH).

zc.buildout is very comfortable here. It will make sure that your  
sandbox will only have those eggs on sys.path that they need, not  
more and not less (even though you can have eggs shared by sandboxes  
so that you'll only have to download and install the same version of  
an egg once).