zulip/zerver/lib/timestamp.py

42 lines
1.4 KiB
Python

import datetime
import calendar
class TimezoneNotUTCException(Exception):
pass
def verify_UTC(dt: datetime.datetime) -> None:
if dt.tzinfo is None or dt.tzinfo.utcoffset(dt) != datetime.timezone.utc.utcoffset(dt):
raise TimezoneNotUTCException(f"Datetime {dt} does not have a UTC timezone.")
def convert_to_UTC(dt: datetime.datetime) -> datetime.datetime:
if dt.tzinfo is None:
return dt.replace(tzinfo=datetime.timezone.utc)
return dt.astimezone(datetime.timezone.utc)
def floor_to_hour(dt: datetime.datetime) -> datetime.datetime:
verify_UTC(dt)
return datetime.datetime(*dt.timetuple()[:4], tzinfo=datetime.timezone.utc)
def floor_to_day(dt: datetime.datetime) -> datetime.datetime:
verify_UTC(dt)
return datetime.datetime(*dt.timetuple()[:3], tzinfo=datetime.timezone.utc)
def ceiling_to_hour(dt: datetime.datetime) -> datetime.datetime:
floor = floor_to_hour(dt)
if floor == dt:
return floor
return floor + datetime.timedelta(hours=1)
def ceiling_to_day(dt: datetime.datetime) -> datetime.datetime:
floor = floor_to_day(dt)
if floor == dt:
return floor
return floor + datetime.timedelta(days=1)
def timestamp_to_datetime(timestamp: float) -> datetime.datetime:
return datetime.datetime.fromtimestamp(float(timestamp), tz=datetime.timezone.utc)
def datetime_to_timestamp(dt: datetime.datetime) -> int:
verify_UTC(dt)
return calendar.timegm(dt.timetuple())