如何在 Django 应用程序中获取原始本地机器时区？

Question

In Django you have a TIME_ZONE setting, which, as I understand, somehow patches the standard date and time packages in runtime, making them think the application is working in the time zone specified. As a result, generic Python methods for determining local time zone do not work (they just show the configured time zone).

I can evaluate the link of /etc/localtime like in this answer or use another Linux-specific method but I am concerned about the portability issue, as some developers run the app on Windows.

Can I find out in a platform independent way what was the original time zone on the machine?

Answer 1

As there were no answers, I will post a workaround here.

Though we cannot recover the initial time zone (without affecting the current settings), we can obtain and save it before Django's initialization. For example:

1. For running locally, we can augment manage.py :

cmd = sys.argv[1] if len(sys.argv) >= 2 else ""
if cmd == "runserver":
    from tzlocal import get_localzone
    os.environ['MACHINE_TIME_ZONE'] = get_localzone().tzname(None)
# ...
execute_from_command_line(sys.argv)

2. For production, the way depends on how you launch the application. For example, if you are using Gunicorn, you can put it into gunicorn.conf.py or wsgi.py . The main thing is tu put it somewhere before loading Django libraries:

from tzlocal import get_localzone
os.environ['MACHINE_TIME_ZONE'] = get_localzone().tzname(None)

Later you can access this environment variable to retrieve the value.