Re: [PHP-DEV] Timezone Rules, which dataset to pick?
On 07/04/2022 11.34, Derick Rethans wrote: > Hi! ... > In the last few years, the maintainer of the Iana TZ Data project has > diverged somewhat from the consensus of the community, and degraded some > data by no longer having an entry for each country and merged timezones > where data does not differ since 1970. (Removing transitions from these > regions where data **does** differ before 1970, even if these were > available). ... > Comments? This article [1] mentions that tzdata can be built in a way to include the "merged away" data: It is possible to build tzdata with PACKRATDATA=backzone if historic pre-1970 data is needed. Would this be an option, too? [1] https://developers.redhat.com/articles/2022/01/28/tzdata-time-zone-database-rhel-2021-update -- Regards, Mike OpenPGP_signature Description: OpenPGP digital signature
Re: [PHP-DEV] Timezone Rules, which dataset to pick?
On Thu, 7 Apr 2022, Nikita Popov wrote: > On Thu, Apr 7, 2022 at 11:34 AM Derick Rethans wrote: > > > Java's date/time maintainer has created a fork based on the original > > Iana TZ data to put back some of the removed/deprecated data to > > better serve their users, and I would think that this is also best > > suited as a data set for PHP. > > > > If you want to read about the intricacies, see: > > https://github.com/JodaOrg/global-tz#rationale > > > > But this does mean a divergence from the "official" TZ data, > > although Joda's data is arguably better. My recommendation is that > > from the 2022b release we switch to Joda's version. (I will today > > merge in the 2022a data from the Iana source.) > > Keeping in mind that people deploying PHP on Linux usually end up > using OS-provided zoneinfo, do you know which source distros base that > on? I think we should follow the distro-consensus here, whatever that > may be. NetBSD has switched, FreeBSD is entertaining the idea and offers the new data as an option. I haven't seen any comments from Linux distributions. Our long standing stance on distributions patching PHP for their own use has always been "you're on your own". The data these users receive is already degraded, due to their patching, and that Iana TZ has already removed some historical data since a few releases. As this removal only pertains pre-1970 data, where the Joda time version provides accurate data for all countries (and not just aribitrary ones), I both don't see that a divergence is a big problem, nor do I find it an argument for releasing known-wrong data. It is mostly African countries now with known-wrong data, but the TZ maintainer tried merging Amsterdam and Brussels (removing likely-correct pre-1970 Dutch data in favour of certainly-wrong pre-1970 Belgium data), and several other European countries. That was stopped for now, but I am certainly he'll try again. I don't think it is acceptable for us to say that we're okay with some countries data to be known-wrong. cheers, Derick -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: https://www.php.net/unsub.php
Re: [PHP-DEV] Timezone Rules, which dataset to pick?
On Thu, Apr 7, 2022 at 11:34 AM Derick Rethans wrote: > Hi! > > As you might be aware, I maintain the date time support in PHP. As part > of that I regularly have to update the rules that timezones employ - > changes in Daylight Saving Time rules, or other changes to rules due to > political foibles. > > In the last few years, the maintainer of the Iana TZ Data project has > diverged somewhat from the consensus of the community, and degraded some > data by no longer having an entry for each country and merged timezones > where data does not differ since 1970. (Removing transitions from these > regions where data **does** differ before 1970, even if these were > available). > > Java's date/time maintainer has created a fork based on the original > Iana TZ data to put back some of the removed/deprecated data to better > serve their users, and I would think that this is also best suited as a > data set for PHP. > > If you want to read about the intricacies, see: > https://github.com/JodaOrg/global-tz#rationale > > But this does mean a divergence from the "official" TZ data, although > Joda's data is arguably better. My recommendation is that from the 2022b > release we switch to Joda's version. (I will today merge in the 2022a > data from the Iana source.) > > Comments? > > If you want to discuss this live, come find me in "Room 11": > https://chat.stackoverflow.com/rooms/11/php > > cheers, > Derick > Keeping in mind that people deploying PHP on Linux usually end up using OS-provided zoneinfo, do you know which source distros base that on? I think we should follow the distro-consensus here, whatever that may be. Regards, Nikita
