Zammad-scheduler constantly crashes if user have unknown timezone

[v-starodubov]

Infos:

• Used Zammad version: 5.2.3
• Installation method: docker-compose
• Operating system: Amazon Linux
• Database + version: MySQL 8.0.23 (Aurora MySQL 3.02.1)
• Elasticsearch version: 7.17.3
• Browser + version: Microsoft Edge 106.0.1370.52 (64-bit)

Expected behavior:

• Zammad set user's timezone to default UTC +00:00 if something wrong.

Actual behavior:

• Zammad-scheduler crashes if user's timezone equals Etc/Unknown

bundler: failed to load command: script/background-worker.rb (script/background-worker.rb)
/usr/local/bundle/gems/activesupport-6.1.7/lib/active_support/core_ext/time/zones.rb:100:in `rescue in find_zone!': Invalid Timezone: Etc/Unknown (ArgumentError)
{...}
/usr/local/bundle/gems/tzinfo-2.0.5/lib/tzinfo/data_source.rb:321:in `validate_timezone_identifier': Invalid identifier: Etc/Unknown (TZInfo::InvalidTimezoneIdentifier)

Steps to reproduce the behavior:

• You must set your browser timezone to Etc/Unknown
  
• Login into Zammad app and wait some time before scheduler start some actions with your session.

To fix crashes you need to start session from another device on same account, where timezone is not broken.

[v-starodubov]

I have investigate more and i think the source of the problem is different. After i changed browser to Mozilla Firefox 106.0.1 (64-bit) the timezone fixed (Europe/Kyiv) i get the same blank field in Branding/Timezone.

And if i change something, zammad-scheduler crashes with error

/usr/local/bundle/gems/activesupport-6.1.7/lib/active_support/core_ext/time/zones.rb:100:in `rescue in find_zone!': Invalid Timezone: Europe/Kyiv (ArgumentError)

And I found that the Branding/Timezone field not Kyiv, but Kiev.

I changed my timezone with plugin to Europe/Berlin, entered zammad app, changed timezone and everything works good.

My operation system: Ubuntu 22.10.
I asked colleague with Windows 10 to check same page, he got filled timezone field with his current timezone.

[v-starodubov]

https://mm.icann.org/pipermail/tz-announce/2022-August/000071.html

[mantas]

Looks like this is 2 separate issues. We ain't handling unknown timezones correctly. It should not crash in any case.

As for Kyiv/Kiev in the dropdown. Kiev/Kyiv in that dropdown relies on timezones data provided by your OS.

[tschaefer]

@mantas We should consider to use the gem tzinfo-data as tz database, at least that would mean we are OS independent.