Files
supervisor/hassio/utils/dt.py
2018-03-13 23:28:38 +01:00

84 lines
2.6 KiB
Python

"""Tools file for HassIO."""
import asyncio
from datetime import datetime, timedelta, timezone
import logging
import re
import aiohttp
import async_timeout
import pytz
UTC = pytz.utc
_LOGGER = logging.getLogger(__name__)
FREEGEOIP_URL = "https://freegeoip.net/json/"
# Copyright (c) Django Software Foundation and individual contributors.
# All rights reserved.
# https://github.com/django/django/blob/master/LICENSE
DATETIME_RE = re.compile(
r'(?P<year>\d{4})-(?P<month>\d{1,2})-(?P<day>\d{1,2})'
r'[T ](?P<hour>\d{1,2}):(?P<minute>\d{1,2})'
r'(?::(?P<second>\d{1,2})(?:\.(?P<microsecond>\d{1,6})\d{0,6})?)?'
r'(?P<tzinfo>Z|[+-]\d{2}(?::?\d{2})?)?$'
)
async def fetch_timezone(websession):
"""Read timezone from freegeoip."""
data = {}
try:
with async_timeout.timeout(10, loop=websession.loop):
async with websession.get(FREEGEOIP_URL) as request:
data = await request.json()
except (aiohttp.ClientError, asyncio.TimeoutError, KeyError) as err:
_LOGGER.warning("Can't fetch freegeoip data: %s", err)
except ValueError as err:
_LOGGER.warning("Error on parse freegeoip data: %s", err)
return data.get('time_zone', 'UTC')
# Copyright (c) Django Software Foundation and individual contributors.
# All rights reserved.
# https://github.com/django/django/blob/master/LICENSE
def parse_datetime(dt_str):
"""Parse a string and return a datetime.datetime.
This function supports time zone offsets. When the input contains one,
the output uses a timezone with a fixed offset from UTC.
Raises ValueError if the input is well formatted but not a valid datetime.
Returns None if the input isn't well formatted.
"""
match = DATETIME_RE.match(dt_str)
if not match:
return None
kws = match.groupdict() # type: Dict[str, Any]
if kws['microsecond']:
kws['microsecond'] = kws['microsecond'].ljust(6, '0')
tzinfo_str = kws.pop('tzinfo')
tzinfo = None # type: Optional[dt.tzinfo]
if tzinfo_str == 'Z':
tzinfo = UTC
elif tzinfo_str is not None:
offset_mins = int(tzinfo_str[-2:]) if len(tzinfo_str) > 3 else 0
offset_hours = int(tzinfo_str[1:3])
offset = timedelta(hours=offset_hours, minutes=offset_mins)
if tzinfo_str[0] == '-':
offset = -offset
tzinfo = timezone(offset)
else:
tzinfo = None
kws = {k: int(v) for k, v in kws.items() if v is not None}
kws['tzinfo'] = tzinfo
return datetime(**kws)
def utcnow():
"""Returns current timestamp including timezone."""
return datetime.now(UTC)