[AstroPy] Healpy

[Peter Williams]

The last paragraph in this FAQ entry:

http://www.gnu.org/licenses/gpl-faq.html#IfInterpreterIsGPL

seems, to me, to make it clear that using a GPL'd module inside an
interpreted program/library (e.g. astropy) obliges you to make it
available under GPL-compatible terms. I am generally positive about the
GPL but I find this to be unfortunate.

I think the best solution in these cases is to provide extension hooks
in the core (BSD/MIT-type-licensed) module so that you can load up an
optional GPL-licensed module so that GPL-only features can be used in a
relatively convenient way through the core module's API.

Peter

On Mon, 2015-10-05 at 12:32 -0400, Perry Greenfield wrote:
> Not if the functionality is essential to the package (at least from
> what I understand). I’ll see if I can dig that aspect of the license
> that specifically mentions it (or legal discussion around it).
> 
> Cheers, Perry
> 
> On Oct 5, 2015, at 12:30 PM, Wolfgang Kerzendorf <
> wkerzendorf at gmail.com> wrote:
> 
> > This is very off topic:
> > 
> > I thought you just can’t ship a non-GPL package with GPL libraries.
> > BUT: If Microsoft makes Word relying on some GPLed library (core
> > -functionality), then they can ship a closed source copy of Word as
> > long as the user needs to download the GPL library from some other
> > source? 
> > 
> > Isn’t that right?
> > 
> > Cheers, 
> >   Wolfgang
> > > On Oct 5, 2015, at 18:20, Perry Greenfield <stsci.perry at gmail.com
> > > > wrote:
> > > 
> > > If that were the case then Python would have to be licensed as
> > > GPL since it uses readline optionally. But it isn’t and I know
> > > that they have looked at that issue carefully. From what I
> > > understand, if the functionality is not core to the package, and
> > > it isn’t bundled with the package, it doesn’t force the licensing
> > > of it. There probably are subtleties here since one might argue
> > > that readline is doesn’t add functionality to Python (but
> > > obviously it does), and healpy does. 
> > > 
> > > In this case I’m inclined to worry unless someone wants to make a
> > > legal issue of it, and in that even about the most that would
> > > happen is a cease-and-desist order. They aren’t going to make a
> > > lot of money suing Astropy (well, given the current checking
> > > account, they are bound to lose a lot of money in legal fees).
> > > 
> > > Perry
> > > 
> > > On Oct 5, 2015, at 12:07 PM, Nathan Goldbaum <
> > > nathan12343 at gmail.com> wrote:
> > > 
> > > > 
> > > > 
> > > > On Sat, Oct 3, 2015 at 2:46 AM, Thomas Robitaille <
> > > > thomas.robitaille at gmail.com> wrote:
> > > > Hi Emil,
> > > > 
> > > > The 'reproject' Astropy-affiliated package provides a way to
> > > > easily
> > > > reproject images using Healpy in addition to astropy.wcs:
> > > > 
> > > > http://reproject.readthedocs.org/en/stable/
> > > > 
> > > > The functionality with Healpy is optional, so the package is
> > > > normally
> > > > BSD-licensed, but if you do install Healpy, then as indicated
> > > > here:
> > > > 
> > > > http://reproject.readthedocs.org/en/stable/healpix.html
> > > > 
> > > > you have to abide by the GPL license instead.
> > > > 
> > > > Hi Tom,
> > > > 
> > > > I don't want to stir up any problems for you, but I don't
> > > > understand how this works legally.
> > > > 
> > > > You're distributing code that imports healpy. Even if it's
> > > > "optional" functionality, the code that imports healpy is being
> > > > distributed under a BSD license. As far as I understand it, the
> > > > intent of the user doesn't matter for the licensing, all that
> > > > matters is the license the code is distributed under.
> > > > 
> > > > I'd strongly urge you to contact e.g. debian-legal or the
> > > > software freedom conservancy about this to get an opinion from
> > > > an expert. I suspect your only legal recourses here are either
> > > > to no longer import healpy in the reproject package or
> > > > relicense reproject under a GPLv2 compatible license.
> > > > 
> > > > -Nathan
> > > > 
> > > > 
> > > > Cheers,
> > > > Tom
> > > > 
> > > > Emil Lenc wrote:
> > > > > Hi All,
> > > > > 
> > > > > I was wondering if there were any plans to incorporate healpy
> > > > > (the python interface to the HEALPIX library) into astropy? I
> > > > > often work between HEALPIX and FITS format images and it
> > > > > would be really convenient to have these two common formats
> > > > > available within the same package.
> > > > > 
> > > > > Cheers,
> > > > > 
> > > > > Emil.
> > > > > _______________________________________________
> > > > > AstroPy mailing list
> > > > > AstroPy at scipy.org
> > > > > https://mail.scipy.org/mailman/listinfo/astropy
> > > > _______________________________________________
> > > > AstroPy mailing list
> > > > AstroPy at scipy.org
> > > > https://mail.scipy.org/mailman/listinfo/astropy
> > > > 
> > > > _______________________________________________
> > > > AstroPy mailing list
> > > > AstroPy at scipy.org
> > > > https://mail.scipy.org/mailman/listinfo/astropy
> > > 
> > > _______________________________________________
> > > AstroPy mailing list
> > > AstroPy at scipy.org
> > > https://mail.scipy.org/mailman/listinfo/astropy
> > 
> > _______________________________________________
> > AstroPy mailing list
> > AstroPy at scipy.org
> > https://mail.scipy.org/mailman/listinfo/astropy
> 
> _______________________________________________
> AstroPy mailing list
> AstroPy at scipy.org
> https://mail.scipy.org/mailman/listinfo/astropy
> 
>