1234477 - Wrong timezone conversion in email notification from Google Calendar

Status: RESOLVED WORKSFORME

(Calendar :: E-mail based Scheduling (iTIP/iMIP), defect)

Description

[Grisha Pushkov]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:44.0) Gecko/20100101 Firefox/44.0
Build ID: 20151214004008

Steps to reproduce:

I have received notification for event from Google Calendar and in "When" field time was converted wrong.
Looking at email source I got this header (not actually a header, header in body):
> When: Tue 22 Dec 2015 12:30pm - 1:30pm Moscow+00 - Moscow

I suppose that Thunderbird understands it as UTC+00 and I get 9:30 – 10:30 time interval, instead of 12:30 – 13:30.

Time in System Preferences is set to UTC+03. I'm using OS X El Capitan 10.11.1.

Comment 1

[[:MakeMyDay]]

What exact version of Lightning and the Google provider do you use?

Comment 2

[Grisha Pushkov]

Lightning 4.0.4.1 as an addon. There is no Google provider installed.

Comment 3

[[:MakeMyDay]]

Ok, I got this probably wrong. Is this your Google calendar (which you access by CalDAV then) or someone elses calendar and you're not using Google calendar yourself? Reading your first statements, I would assume the latter now.

In general, this is an unusual way to specify timezones - either one uses Moscow or the utc offset. But maybe this is just handled that way in the displayed part of the message.

Can you please attach the complete message to this bug (if you want to modify information for privacy reasons before, please to it in a way without changing the information structure)?

Comment 4

[Grisha Pushkov]

Yes, I was quite inaccurate that it's email notification and not CalDAV thing.
Here is the source of the message: https://pastebin.mozilla.org/8855138.

I can't get what Thunderbird type uses (plain or HTML). Changing "View -> Message Body As" doesn't change anything. But definitely time conversion has a place to be, because in source I see:
> When: Tue 22 Dec 2015 12:30pm - 1:30pm Moscow+00 - Moscow
and in the rendered message:
> 22 декабря 2015 г. 9:30 – 10:30

Comment 5

[[:MakeMyDay]]

This seems not to be the complete message - there is no ics part within and even the html part seems not to be complete. For analysis the whole message is needed. If this is all you have, maybe the mesage is corrupt.

The lines you're quoting are usually not used to extract the meeting information from the message (except you have used email to calendar conversion, what is typically not neccessary for email invitations).

Comment 6

[Grisha Pushkov]

Full message: https://pastebin.mozilla.org/8855140.

Comment 7

[[:MakeMyDay]]

Lightning behaves correctly. The specified start and end times are explicitely utc without any offset (z suffix is equivalent to UTC)

>DTSTART:20151222T093000Z
>DTEND:20151222T103000Z

So this is a Google issue or maybe related to a faulty operation/configuration of the sender.

Comment 8

[[:MakeMyDay]]

What timezone do you have configured as your local timezone in Lightning? If none, you should do that.

Comment 9

[Grisha Pushkov]

> >DTSTART:20151222T093000Z
> >DTEND:20151222T103000Z
>
> So this is a Google issue or maybe related to a faulty operation/configuration of the sender.

It seems to be right – 09:30 in UTC+00 should be displayed as 12:30 for my UTC+03.

Comment 10

[Grisha Pushkov]

Ok, now it's displayed correctly!
I have changed timezone in "Preferences - Calendar - General - Timezon - Europe/Moscow".

Comment 11

[Grisha Pushkov]

Maybe setting `calendar.timezone.local` automatically is a good idea?

Comment 12

[Grisha Pushkov]

I had "floating" value by default.

Comment 13

[[:MakeMyDay]]

Resolving this to wfm as per comment 10.

Setting this without user interaction in a relibale cannot be always achived. For devices that provide their position it would be a valuable option, but usually desktop systems (and also notebooks) don't do so. That said, an automated detection may end up in not wanted results, so it's up to the user to set the proper timezone atm.

Comment 14

[Grisha Pushkov]

So Thunderbird can't get system timezone?
Something like to what _/etc/localtime_ links in Unix systems, for example.

Comment 15

[[:MakeMyDay]]

What you want is probably bug 1129963.