I was really surprised to not find an easy way to do this in Python. We wrote this in December and it passed, because it was winter:
def get_utc_time(dt_or_str, number_of_days=None, time_format=DATETIME_FORMAT):
"""
:param dt_or_str:
:return:
"""
eastern = pytz.timezone('US/Eastern')
# try:
if isinstance(dt_or_str, datetime):
new_date_str = dt_or_str.strftime(time_format)
new_date_obj = dt_or_str
else:
new_date_str = dt_or_str
new_date_obj = datetime.strptime(dt_or_str, time_format)
if not number_of_days:
utc_time = eastern.localize(
datetime.strptime(new_date_str, time_format),
is_dst=None).astimezone(pytz.utc)
else:
est_time = new_date_obj - timedelta(days=number_of_days)
utc_time = eastern.localize(est_time, is_dst=None).astimezone(pytz.utc)
utc_time = utc_time.replace(tzinfo=None)
What this did is add 5 hours to your time to make it UTC. It turns out in Spring/Summer Eastern time is only 4 hours behind UTC, so our code is now broken.
This is the test we wrote that does not work in Summer:
def test_get_utc_time_incoming_string(self):
result = get_utc_time("2017-02-02 04:38")
self.assertEqual(result, datetime.datetime(2017, 2, 2, 8, 38))
How can you convert EST to UTC that will work year round? I don't want to hard code it since daylight savings period changes each year.
Found this on an answer:
def is_daylight_savings(timezone_name):
tz = pytz.timezone(timezone_name)
now = pytz.utc.localize(datetime.utcnow())
return now.astimezone(tz).dst() != timedelta(0)
so now this:
def get_utc_time(dt_or_str, number_of_days=None, time_format=DATETIME_FORMAT):
"""
:param dt_or_str:
:return:
"""
eastern = pytz.timezone(TIMEZONE)
it_is_daylight_savings = is_daylight_savings(TIMEZONE)
if isinstance(dt_or_str, datetime):
new_date_str = dt_or_str.strftime(time_format)
new_date_obj = dt_or_str
else:
new_date_str = dt_or_str
new_date_obj = datetime.strptime(dt_or_str, time_format)
if not number_of_days:
utc_time = eastern.localize(
datetime.strptime(new_date_str, time_format),
is_dst=it_is_daylight_savings).astimezone(pytz.utc)
else:
est_time = new_date_obj - timedelta(days=number_of_days)
utc_time = eastern.localize(est_time, is_dst=it_is_daylight_savings).astimezone(pytz.utc)
utc_time = utc_time.replace(tzinfo=None)
return utc_time
as freedom of speech dies, freedom to be rude increases exponentionally