zulip/zerver/lib/timestamp.py

50 lines
1.2 KiB
Python

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