[PROJ] PROJ 7.0.0RC1

[Bas Couwenberg]

On 2020-02-18 13:45, Even Rouault wrote:
>> Hence it seems that proj-datumgrid itself is not entirely superseded 
>> by
>> proj-data, unlike the regional archives.
> 
> For "normal" users, proj-datumgrid should be deprecated. We indeed need 
> a few
> "old" grids for the tests, that can be fetched for there. We could 
> potentially
> consider just dumping them, or a spatial subset of them, in PROJ main 
> repo,
> now that we have a data/for_tests subdirectory.

Including the grids required for tests in the proj tree is a good idea, 
although it's also nice to have them automatically installed in 
/usr/share/proj to not need the CDN for those grids.

>> Packaging proj-data has the same problem as proj-datumgrid regional
>> archive, it's a PITA to maintain the copyright file for the various
>> grids
> 
> How can we help for that ? We have the README files with all copyright 
> and
> licensing information.

What's documented in the README currently is good enough to know which 
license applies to which file, but it lacks a copyright statement like 
you'll find in source code.

> I guess you may have some required formalism for the
> sake of Debian packaging.

We use the machine readable format for the packages maintained by the 
Debian GIS team:

  https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/

The file generally consists of blocks of files grouped by license, e.g.:

  Files: *
  Copyright: 2019-2020, John Doe <jdoe at example.com>
                  2020, Alice Bob <alice at example.com>
  License: GPL-3+

  Files: foo.c
   bar.c
  Copyright: 1980-1995, Foo Corp
  License: BSD-3-Clause

The above is a common case where most of the project code has common 
copyright holders, and a few sources from other origins are included 
with their own license & copyright.

For the datumgrids the copyright holders & license differs for most 
files, requiring Files blocks for every agency which is doable, but we 
can't rely on the licensecheck tool to generate most of the copyright 
file for us.

> Would a CSV file like
> https://github.com/OSGeo/proj-datumgrid/blob/master/filelist.csv be 
> helpful,
> with filename, copyright and license columns, so that you can automate 
> the
> building of the Debian copyright file ?

It would be helpful if it had a copyright column, that's the biggest 
piece of missing information we'd need to hunt down if we were to 
package proj-data for Debian.

> That .csv file was created to automate
> the mass conversion of GTX & NTv2 grids to GeoTIFF files. It could be a 
> good
> start if we wanted to resurect it in PROJ-data repository for the sake 
> of
> easing maintaining copyright informatio
> I'd note also that all GeoTIFF file in PROJ-data embed copyright & 
> licensing
> info in TIFF metadata.

If adding grids to proj-data not only requires the license to be 
documented but also the copyright statement, that would at least make 
sure that packages don't need to hunt for that information every time 
grids are added. We still need to do that for all the grids currently 
included. And that's not a task I'm want to spend my time on.

Kind Regards,

Bas