Bug#954112: tzdata: Add ICU tzdata files

[Aurelien Jarno <aurelien@aurel32.net>]

control: tag -1 +moreinfo

Hi,

On 2020-10-19 21:02, Aurelien Jarno wrote:
> Hi,
> 
> On 2020-10-19 14:56, Dimitri John Ledkov wrote:
> > On Mon, 16 Mar 2020 23:09:58 +0000 Dimitri John Ledkov <xnox@ubuntu.com> wrote:
> > > Package: tzdata
> > > Version: 2019c-3
> > > Severity: normal
> > >
> > > Dear Maintainer,
> > >
> > > This adds ICU timezone datafiles from icu-data repository.
> > >
> > > The source .txt data files are sources for the binary .res files,
> > > which are compiled at build time. Shipping this enabled to update
> > > timezone database files at runtime for icu, by rebuilding icu by
> > > setting `U_TIMEZONE_FILES_DIR` build-time config option, or at runtime
> > > with environment variable `ICU_TIMEZONE_FILES_DIR`. This will resolve
> > > a long standing bug that tzdata inside icu is never updated, and thus
> > > apps that use icu to access tzdata are always out of date (i.e. php).
> > >
> > > Note that the .txt files do duplicate tzdata data files a bit. As they
> > > are generated with a Java app by ICU upstream which merges tzdata
> > > files as input together with https://github.com/unicode-org/cldr xmls
> > > overrides. Maybe in the future, I will provide a more complete /
> > > reproducible process to rebuild icu input .txt files from the tzdata
> > > files directly with the xml overlays "from complete scratch".
> > >
> > > However, at least .res files generated are reproducible and match
> > > checksums of the prebuild .res files distributed in the icu-data
> > > repository.
> > >
> > > Regards,
> > >
> > > Dimitri.
> > 
> > Hi, Is this going to be reviewed / considered for inclusion?
> > 
> > icu package in Debian now compiles with such a definition too, and is
> > actively trying to lookup updated tzdata from that location.

I got a look at that patch, and I fail to see why it should be part of
the tzdata source package:
- it doesn't use any files from the tzdata sources
- the unicode-org github repository is not updated synchronously with
  tzdata, and even lagging by a few versions (currently it only has
  2020d instead of 2020f). This would prevent use to ship new tzdata
  versions until the unicode-org repository is updated.

In that regard it would be better to just ship and independent
tzdata-icu source package instead.

Regards,
Aurelien

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurelien@aurel32.net                 http://www.aurel32.net