Python Packages : A looming problem? packages might no longer work? (well not on your platform or python version anyway)

[Steven D'Aprano]

On Wed, 22 Apr 2009 23:27:23 -0400, David Lyon wrote:


>> Why? Why should every package on PyPI need to support all those Python
>> versions? That should be the decision of the package maintainer. If
>> they want to support every version of Python back to 1.0, they can, and
>> if they want to only support version 2.5 that's fine too.
> 
> Why shouldn't packages support more than one python version?

They can. That depends on the developer of the package.


> Looking at it conversely....
> 
> Why should the package developer dictacte which python version the
> package will run on ?

Because they're the developer. Who else should decide what Python 
versions to support? What are you going to do, hold a gun to their head 
and force them to support Python 2.1 when they've written it using 2.6 
features?



>> For all we know, three quarters of the packages on PyPI have never been
>> tested *at all*.
> 
> Right. Why not run some tests....

Be my guest.


>> What's the dire problem you are trying to solve?
> 
> Backward and forward compatability of python package resources.

That's not a problem, that's a feature.

What's the *problem* that you are trying to solve? What bad thing will 
happen if we don't build your proposed system?


>> What "Super-Computers" do you know of that run Python?
> 
> Google. Amazon web services..

They're not super computers. They're distributed networks of "regular" 
computers.


>> Who is paying for this?
> 
>>From as little as $30 per month. Funding isn't so much the issue.

Whether it is $30 a month or $30,000 a month, who do you expect to pay it?


>>> With this basic structure, a daily building/testing infrastructure
>>> working across the different versions of python and operating systems,
>>> could easily become a reality.
>> 
>> Oh yeah, "easily".
> 
> pypi_packagelist = getallpypipackages()
> 
> for package in pypi_packagelist:
>     testpackageonallplatforms(package)


You don't have either getallpypipackages() or 
testpackageonallplatforms(), so this is just Py in the Sky (pun intended) 
fantasizing. But okay, for the sake of the argument, let's pretend you 
have your cluster, and your test suite. You run the test, and get a list 
of 18,000 errors (that's an average of three errors per package). Now 
what?




-- 
Steven