Files
osxphotos/osxphotos/datetime_utils.py

63 lines
1.8 KiB
Python

""" datetime utilities """
import datetime
def get_local_tz(dt):
""" return local timezone as datetime.timezone tzinfo for dt
Args:
dt: datetime.datetime
Returns:
local timezone for dt as datetime.timezone
Raises:
ValueError if dt is not timezone naive
"""
if not datetime_has_tz(dt):
return dt.astimezone().tzinfo
else:
raise ValueError("dt must be naive datetime.datetime object")
def datetime_remove_tz(dt):
""" remove timezone from a datetime.datetime object
dt: datetime.datetime object with tzinfo
returns: dt without any timezone info (naive datetime object) """
if type(dt) != datetime.datetime:
raise TypeError(f"dt must be type datetime.datetime, not {type(dt)}")
return dt.replace(tzinfo=None)
def datetime_has_tz(dt):
""" return True if datetime dt has tzinfo else False
dt: datetime.datetime
returns True if dt is timezone aware, else False """
if type(dt) != datetime.datetime:
raise TypeError(f"dt must be type datetime.datetime, not {type(dt)}")
return dt.tzinfo is not None and dt.tzinfo.utcoffset(dt) is not None
def datetime_naive_to_local(dt):
""" convert naive (timezone unaware) datetime.datetime
to aware timezone in local timezone
dt: datetime.datetime without timezone
returns: datetime.datetime with local timezone """
if type(dt) != datetime.datetime:
raise TypeError(f"dt must be type datetime.datetime, not {type(dt)}")
if dt.tzinfo is not None and dt.tzinfo.utcoffset(dt) is not None:
# has timezone info
raise ValueError(
"dt must be naive/timezone unaware: "
f"{dt} has tzinfo {dt.tzinfo} and offset {dt.tizinfo.utcoffset(dt)}"
)
return dt.replace(tzinfo=get_local_tz(dt))