Today, I was looking at fedocal as I found out it could not import its own iCal files.
Well, to be exact, the import worked fine but then it was not able to display the meeting. The source of the issue is that the iCal output is relying on timezone name such as EDT or CEST while fedocal actually expects timezone to be of type US/Eastern or Europe/Paris.
So I went looking for a way to convert the acronyms to real timezone.
I finally found out the following script:
import pytz
from datetime import datetime
timezone_lookup = dict()
for tz in pytz.common_timezones:
name = pytz.timezone(tz).localize(datetime.now()).tzname()
if key in timezone_lookup:
timezone_lookup[name].append(tz)
else:
timezone_lookup[name] = [tz]
for key in sorted(timezone_lookup):
print key, timezone_lookup[key]
Which led me to discover things like:
IST ['Asia/Colombo', 'Asia/Kolkata', 'Europe/Dublin']
The Indian Standard Time and the Irish Standard Time have the same acronym
but also:
EST ['America/Atikokan', 'America/Cayman', 'America/Jamaica', 'America/Panama', 'Australia/Brisbane', 'Australia/Currie', 'Australia/Hobart', 'Australia/Lindeman', 'Australia/Melbourne', 'Australia/Sydney']
So how to handle this?
The only solution I could came up with is relying on both the acronym and the offset between that timezone and UTC
Adjusted script:
import pytz
from datetime import datetime
timezone_lookup = dict()
for tz in pytz.common_timezones:
name = pytz.timezone(tz).localize(datetime.now()).tzname()
offset = pytz.timezone(tz).localize(datetime.now()).utcoffset()
key = (name, offset)
if key in timezone_lookup:
timezone_lookup[key].append(tz)
else:
timezone_lookup[key] = [tz]
for key in sorted(timezone_lookup):
print key, timezone_lookup[key]
And corresponding output:
...
('EST', datetime.timedelta(-1, 68400)) ['America/Atikokan', 'America/Cayman', 'America/Jamaica', 'America/Panama']
('EST', datetime.timedelta(0, 36000)) ['Australia/Brisbane', 'Australia/Currie', 'Australia/Hobart', 'Australia/Lindeman', 'Australia/Melbourne', 'Australia/Sydney']
...
('IST', datetime.timedelta(0, 3600)) ['Europe/Dublin']
('IST', datetime.timedelta(0, 19800)) ['Asia/Colombo', 'Asia/Kolkata']
...
So much fun...
