import enum
import logging
import re
-from typing import NewType, Tuple
+from typing import Any, NewType, Tuple
import holidays # type: ignore
import pytz
logger = logging.getLogger(__name__)
+def is_timezone_aware(dt: datetime.datetime) -> bool:
+ """See: https://docs.python.org/3/library/datetime.html
+ #determining-if-an-object-is-aware-or-naive
+
+ >>> is_timezone_aware(datetime.datetime.now())
+ False
+
+ >>> is_timezone_aware(now_pacific())
+ True
+
+ """
+ return (
+ dt.tzinfo is not None and
+ dt.tzinfo.utcoffset(dt) is not None
+ )
+
+
+def is_timezone_naive(dt: datetime.datetime) -> bool:
+ return not is_timezone_aware(dt)
+
+
def replace_timezone(dt: datetime.datetime,
tz: datetime.tzinfo) -> datetime.datetime:
+ """
+ Replaces the timezone on a datetime object directly (leaving
+ the year, month, day, hour, minute, second, micro, etc... alone).
+ Note: this changes the instant to which this dt refers.
+
+ >>> from pytz import UTC
+ >>> d = now_pacific()
+ >>> d.tzinfo.tzname(d)[0] # Note: could be PST or PDT
+ 'P'
+ >>> h = d.hour
+ >>> o = replace_timezone(d, UTC)
+ >>> o.tzinfo.tzname(o)
+ 'UTC'
+ >>> o.hour == h
+ True
+
+ """
+ return datetime.datetime(
+ dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second, dt.microsecond,
+ tzinfo=tz
+ )
+
+
+def replace_time_timezone(t: datetime.time,
+ tz: datetime.tzinfo) -> datetime.time:
+ """
+ Replaces the timezone on a datetime.time directly without performing
+ any translation.
+
+ >>> t = datetime.time(8, 15, 12, 0, pytz.UTC)
+ >>> t.tzname()
+ 'UTC'
+
+ >>> t = replace_time_timezone(t, pytz.timezone('US/Pacific'))
+ >>> t.tzname()
+ 'US/Pacific'
+
+ """
+ return t.replace(tzinfo=tz)
+
+
+def translate_timezone(dt: datetime.datetime,
+ tz: datetime.tzinfo) -> datetime.datetime:
+ """
+ Translates dt into a different timezone by adjusting the year, month,
+ day, hour, minute, second, micro, etc... appropriately. The returned
+ dt is the same instant in another timezone.
+
+ >>> from pytz import UTC
+ >>> d = now_pacific()
+ >>> d.tzinfo.tzname(d)[0] # Note: could be PST or PDT
+ 'P'
+ >>> h = d.hour
+ >>> o = translate_timezone(d, UTC)
+ >>> o.tzinfo.tzname(o)
+ 'UTC'
+ >>> o.hour == h
+ False
+
+ """
return dt.replace(tzinfo=None).astimezone(tz=tz)
def now() -> datetime.datetime:
+ """
+ What time is it? Result returned in UTC
+ """
return datetime.datetime.now()
-def now_pst() -> datetime.datetime:
- return replace_timezone(now(), pytz.timezone("US/Pacific"))
+def now_pacific() -> datetime.datetime:
+ """
+ What time is it? Result in US/Pacific time (PST/PDT)
+ """
+ return datetime.datetime.now(pytz.timezone("US/Pacific"))
def date_to_datetime(date: datetime.date) -> datetime.datetime:
+ """
+ Given a date, return a datetime with hour/min/sec zero (midnight)
+
+ >>> import datetime
+ >>> date_to_datetime(datetime.date(2021, 12, 25))
+ datetime.datetime(2021, 12, 25, 0, 0)
+
+ """
return datetime.datetime(
date.year,
date.month,
)
+def time_to_datetime_today(time: datetime.time) -> datetime.datetime:
+ """
+ Given a time, returns that time as a datetime with a date component
+ set based on the current date. If the time passed is timezone aware,
+ the resulting datetime will also be (and will use the same tzinfo).
+ If the time is timezone naive, the datetime returned will be too.
+
+ >>> t = datetime.time(13, 14, 0)
+ >>> d = now_pacific().date()
+ >>> dt = time_to_datetime_today(t)
+ >>> dt.date() == d
+ True
+
+ >>> dt.time() == t
+ True
+
+ >>> dt.tzinfo == t.tzinfo
+ True
+
+ >>> dt.tzinfo == None
+ True
+
+ >>> t = datetime.time(8, 15, 12, 0, pytz.UTC)
+ >>> t.tzinfo == None
+ False
+
+ >>> dt = time_to_datetime_today(t)
+ >>> dt.tzinfo == None
+ False
+
+ """
+ now = now_pacific()
+ tz = time.tzinfo
+ return datetime.datetime.combine(now, time, tz)
+
+
def date_and_time_to_datetime(date: datetime.date,
time: datetime.time) -> datetime.datetime:
+ """
+ Given a date and time, merge them and return a datetime.
+
+ >>> import datetime
+ >>> d = datetime.date(2021, 12, 25)
+ >>> t = datetime.time(12, 30, 0, 0)
+ >>> date_and_time_to_datetime(d, t)
+ datetime.datetime(2021, 12, 25, 12, 30)
+
+ """
return datetime.datetime(
date.year,
date.month,
time.hour,
time.minute,
time.second,
- time.millisecond
+ time.microsecond,
)
-def datetime_to_date(date: datetime.datetime) -> datetime.date:
- return datetime.date(
- date.year,
- date.month,
- date.day
- )
+def datetime_to_date_and_time(
+ dt: datetime.datetime
+) -> Tuple[datetime.date, datetime.time]:
+ """Return the component date and time objects of a datetime.
+
+ >>> import datetime
+ >>> dt = datetime.datetime(2021, 12, 25, 12, 30)
+ >>> (d, t) = datetime_to_date_and_time(dt)
+ >>> d
+ datetime.date(2021, 12, 25)
+ >>> t
+ datetime.time(12, 30)
+
+ """
+ return (dt.date(), dt.timetz())
+
+
+def datetime_to_date(dt: datetime.datetime) -> datetime.date:
+ """Return the date part of a datetime.
+
+ >>> import datetime
+ >>> dt = datetime.datetime(2021, 12, 25, 12, 30)
+ >>> datetime_to_date(dt)
+ datetime.date(2021, 12, 25)
+
+ """
+ return datetime_to_date_and_time(dt)[0]
+
+
+def datetime_to_time(dt: datetime.datetime) -> datetime.time:
+ """Return the time part of a datetime.
+
+ >>> import datetime
+ >>> dt = datetime.datetime(2021, 12, 25, 12, 30)
+ >>> datetime_to_time(dt)
+ datetime.time(12, 30)
+
+ """
+ return datetime_to_date_and_time(dt)[1]
-# An enum to represent units with which we can compute deltas.
class TimeUnit(enum.Enum):
+ """An enum to represent units with which we can compute deltas."""
MONDAYS = 0
TUESDAYS = 1
WEDNESDAYS = 2
MONTHS = 13
YEARS = 14
+ @classmethod
+ def is_valid(cls, value: Any):
+ if type(value) is int:
+ return value in cls._value2member_map_
+ elif type(value) is TimeUnit:
+ return value.value in cls._value2member_map_
+ elif type(value) is str:
+ return value in cls._member_names_
+ else:
+ print(type(value))
+ return False
+
def n_timeunits_from_base(
count: int,
unit: TimeUnit,
base: datetime.datetime
) -> datetime.datetime:
+ """Return a datetime that is N units before/after a base datetime.
+ e.g. 3 Wednesdays from base datetime, 2 weeks from base date, 10
+ years before base datetime, 13 minutes after base datetime, etc...
+ Note: to indicate before/after the base date, use a positive or
+ negative count.
+
+ >>> base = string_to_datetime("2021/09/10 11:24:51AM-0700")[0]
+
+ The next (1) Monday from the base datetime:
+ >>> n_timeunits_from_base(+1, TimeUnit.MONDAYS, base)
+ datetime.datetime(2021, 9, 13, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Ten (10) years after the base datetime:
+ >>> n_timeunits_from_base(10, TimeUnit.YEARS, base)
+ datetime.datetime(2031, 9, 10, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Fifty (50) working days (M..F, not counting holidays) after base datetime:
+ >>> n_timeunits_from_base(50, TimeUnit.WORKDAYS, base)
+ datetime.datetime(2021, 11, 23, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Fifty (50) days (including weekends and holidays) after base datetime:
+ >>> n_timeunits_from_base(50, TimeUnit.DAYS, base)
+ datetime.datetime(2021, 10, 30, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Fifty (50) months before (note negative count) base datetime:
+ >>> n_timeunits_from_base(-50, TimeUnit.MONTHS, base)
+ datetime.datetime(2017, 7, 10, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Fifty (50) hours after base datetime:
+ >>> n_timeunits_from_base(50, TimeUnit.HOURS, base)
+ datetime.datetime(2021, 9, 12, 13, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Fifty (50) minutes before base datetime:
+ >>> n_timeunits_from_base(-50, TimeUnit.MINUTES, base)
+ datetime.datetime(2021, 9, 10, 10, 34, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ Fifty (50) seconds from base datetime:
+ >>> n_timeunits_from_base(50, TimeUnit.SECONDS, base)
+ datetime.datetime(2021, 9, 10, 11, 25, 41, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ """
+ assert TimeUnit.is_valid(unit)
if count == 0:
return base
timedelta = datetime.timedelta(days=count)
return base + timedelta
+ # N hours from base
+ elif unit == TimeUnit.HOURS:
+ timedelta = datetime.timedelta(hours=count)
+ return base + timedelta
+
+ # N minutes from base
+ elif unit == TimeUnit.MINUTES:
+ timedelta = datetime.timedelta(minutes=count)
+ return base + timedelta
+
+ # N seconds from base
+ elif unit == TimeUnit.SECONDS:
+ timedelta = datetime.timedelta(seconds=count)
+ return base + timedelta
+
# N workdays from base
elif unit == TimeUnit.WORKDAYS:
if count < 0:
base.minute,
base.second,
base.microsecond,
+ base.tzinfo,
)
# N years from base
base.minute,
base.second,
base.microsecond,
+ base.tzinfo,
)
+ if unit not in set([TimeUnit.MONDAYS,
+ TimeUnit.TUESDAYS,
+ TimeUnit.WEDNESDAYS,
+ TimeUnit.THURSDAYS,
+ TimeUnit.FRIDAYS,
+ TimeUnit.SATURDAYS,
+ TimeUnit.SUNDAYS]):
+ raise ValueError(unit)
+
# N weekdays from base (e.g. 4 wednesdays from today)
direction = 1 if count > 0 else -1
count = abs(count)
start = base
while True:
dow = base.weekday()
- if dow == unit and start != base:
+ if dow == unit.value and start != base:
count -= 1
if count == 0:
return base
include_fractional=False,
twelve_hour=True,
) -> str:
+ """
+ Helper to return a format string without looking up the documentation
+ for strftime.
+
+ >>> get_format_string()
+ '%Y/%m/%d %I:%M:%S%p%z'
+
+ >>> get_format_string(date_time_separator='@')
+ '%Y/%m/%d@%I:%M:%S%p%z'
+
+ >>> get_format_string(include_dayname=True)
+ '%a/%Y/%m/%d %I:%M:%S%p%z'
+
+ >>> get_format_string(include_dayname=True, twelve_hour=False)
+ '%a/%Y/%m/%d %H:%M:%S%z'
+
+ """
fstring = ""
if include_dayname:
fstring += "%a/"
if use_month_abbrevs:
- fstring = f"%Y/%b/%d{date_time_separator}"
+ fstring = f"{fstring}%Y/%b/%d{date_time_separator}"
else:
- fstring = f"%Y/%m/%d{date_time_separator}"
+ fstring = f"{fstring}%Y/%m/%d{date_time_separator}"
if twelve_hour:
fstring += "%I:%M"
if include_seconds:
include_fractional=False,
twelve_hour=True,
) -> str:
- """A nice way to convert a datetime into a string."""
+ """
+ A nice way to convert a datetime into a string; arguably better than
+ just printing it and relying on it __repr__().
+
+ >>> d = string_to_datetime(
+ ... "2021/09/10 11:24:51AM-0700",
+ ... )[0]
+ >>> d
+ datetime.datetime(2021, 9, 10, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+ >>> datetime_to_string(d)
+ '2021/09/10 11:24:51AM-0700'
+ >>> datetime_to_string(d, include_dayname=True, include_seconds=False)
+ 'Fri/2021/09/10 11:24AM-0700'
+
+ """
fstring = get_format_string(
date_time_separator=date_time_separator,
include_timezone=include_timezone,
include_fractional=False,
twelve_hour=True,
) -> Tuple[datetime.datetime, str]:
- """A nice way to convert a string into a datetime. Also consider
- dateparse.dateparse_utils for a full parser.
+ """A nice way to convert a string into a datetime. Returns both the
+ datetime and the format string used to parse it. Also consider
+ dateparse.dateparse_utils for a full parser alternative.
+
+ >>> d = string_to_datetime(
+ ... "2021/09/10 11:24:51AM-0700",
+ ... )
+ >>> d
+ (datetime.datetime(2021, 9, 10, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200))), '%Y/%m/%d %I:%M:%S%p%z')
+
"""
fstring = get_format_string(
date_time_separator=date_time_separator,
def timestamp() -> str:
- """Return a timestamp for now in Pacific timezone."""
+ """Return a timestamp for right now in Pacific timezone."""
ts = datetime.datetime.now(tz=pytz.timezone("US/Pacific"))
return datetime_to_string(ts, include_timezone=True)
include_timezone=False,
twelve_hour=True,
) -> str:
- """A nice way to convert a datetime into a time (only) string."""
+ """A nice way to convert a datetime into a time (only) string.
+ This ignores the date part of the datetime.
+
+ >>> d = string_to_datetime(
+ ... "2021/09/10 11:24:51AM-0700",
+ ... )[0]
+ >>> d
+ datetime.datetime(2021, 9, 10, 11, 24, 51, tzinfo=datetime.timezone(datetime.timedelta(days=-1, seconds=61200)))
+
+ >>> time_to_string(d)
+ '11:24:51AM'
+
+ >>> time_to_string(d, include_seconds=False)
+ '11:24AM'
+
+ >>> time_to_string(d, include_seconds=False, include_timezone=True)
+ '11:24AM-0700'
+
+ """
fstring = ""
if twelve_hour:
fstring += "%l:%M"
def minute_number(hour: int, minute: int) -> MinuteOfDay:
- """Convert hour:minute into minute number from start of day."""
+ """
+ Convert hour:minute into minute number from start of day.
+
+ >>> minute_number(0, 0)
+ 0
+
+ >>> minute_number(9, 15)
+ 555
+
+ >>> minute_number(23, 59)
+ 1439
+
+ """
return MinuteOfDay(hour * 60 + minute)
def datetime_to_minute_number(dt: datetime.datetime) -> MinuteOfDay:
- """Convert a datetime into a minute number (of the day)"""
+ """
+ Convert a datetime into a minute number (of the day). Note that
+ this ignores the date part of the datetime and only uses the time
+ part.
+
+ >>> d = string_to_datetime(
+ ... "2021/09/10 11:24:51AM-0700",
+ ... )[0]
+
+ >>> datetime_to_minute_number(d)
+ 684
+
+ """
return minute_number(dt.hour, dt.minute)
+def time_to_minute_number(t: datetime.time) -> MinuteOfDay:
+ """
+ Convert a datetime.time into a minute number.
+
+ >>> t = datetime.time(5, 15)
+ >>> time_to_minute_number(t)
+ 315
+
+ """
+ return minute_number(t.hour, t.minute)
+
+
def minute_number_to_time_string(minute_num: MinuteOfDay) -> str:
- """Convert minute number from start of day into hour:minute am/pm
+ """
+ Convert minute number from start of day into hour:minute am/pm
string.
+
+ >>> minute_number_to_time_string(315)
+ ' 5:15a'
+
+ >>> minute_number_to_time_string(684)
+ '11:24a'
+
"""
hour = minute_num // 60
minute = minute_num % 60
def parse_duration(duration: str) -> int:
- """Parse a duration in string form."""
+ """
+ Parse a duration in string form into a delta seconds.
+
+ >>> parse_duration('15 days, 2 hours')
+ 1303200
+
+ >>> parse_duration('15d 2h')
+ 1303200
+
+ >>> parse_duration('100s')
+ 100
+
+ >>> parse_duration('3min 2sec')
+ 182
+
+ """
+ if duration.isdigit():
+ return int(duration)
seconds = 0
m = re.search(r'(\d+) *d[ays]*', duration)
if m is not None:
return seconds
-def describe_duration(age: int) -> str:
- """Describe a duration."""
- days = divmod(age, constants.SECONDS_PER_DAY)
+def describe_duration(seconds: int, *, include_seconds = False) -> str:
+ """
+ Describe a duration represented as a count of seconds nicely.
+
+ >>> describe_duration(182)
+ '3 minutes'
+
+ >>> describe_duration(182, include_seconds=True)
+ '3 minutes, and 2 seconds'
+
+ >>> describe_duration(100, include_seconds=True)
+ '1 minute, and 40 seconds'
+
+ describe_duration(1303200)
+ '15 days, 2 hours'
+
+ """
+ days = divmod(seconds, constants.SECONDS_PER_DAY)
hours = divmod(days[1], constants.SECONDS_PER_HOUR)
minutes = divmod(hours[1], constants.SECONDS_PER_MINUTE)
descr = f"{int(days[0])} days, "
elif days[0] == 1:
descr = "1 day, "
+
if hours[0] > 1:
descr = descr + f"{int(hours[0])} hours, "
elif hours[0] == 1:
descr = descr + "1 hour, "
- if len(descr) > 0:
+
+ if not include_seconds and len(descr) > 0:
descr = descr + "and "
+
if minutes[0] == 1:
descr = descr + "1 minute"
else:
descr = descr + f"{int(minutes[0])} minutes"
+
+ if include_seconds:
+ descr = descr + ', '
+ if len(descr) > 0:
+ descr = descr + 'and '
+ s = minutes[1]
+ if s == 1:
+ descr = descr + '1 second'
+ else:
+ descr = descr + f'{s} seconds'
return descr
-def describe_duration_briefly(age: int) -> str:
- """Describe a duration briefly."""
- days = divmod(age, constants.SECONDS_PER_DAY)
+def describe_timedelta(delta: datetime.timedelta) -> str:
+ """
+ Describe a duration represented by a timedelta object.
+
+ >>> d = datetime.timedelta(1, 600)
+ >>> describe_timedelta(d)
+ '1 day, and 10 minutes'
+
+ """
+ return describe_duration(delta.total_seconds())
+
+
+def describe_duration_briefly(seconds: int, *, include_seconds=False) -> str:
+ """
+ Describe a duration briefly.
+
+ >>> describe_duration_briefly(182)
+ '3m'
+
+ >>> describe_duration_briefly(182, include_seconds=True)
+ '3m 2s'
+
+ >>> describe_duration_briefly(100, include_seconds=True)
+ '1m 40s'
+
+ describe_duration_briefly(1303200)
+ '15d 2h'
+
+ """
+ days = divmod(seconds, constants.SECONDS_PER_DAY)
hours = divmod(days[1], constants.SECONDS_PER_HOUR)
minutes = divmod(hours[1], constants.SECONDS_PER_MINUTE)
- descr = ""
+ descr = ''
if days[0] > 0:
- descr = f"{int(days[0])}d "
+ descr = f'{int(days[0])}d '
if hours[0] > 0:
- descr = descr + f"{int(hours[0])}h "
- if minutes[0] > 0 or len(descr) == 0:
- descr = descr + f"{int(minutes[0])}m"
+ descr = descr + f'{int(hours[0])}h '
+ if minutes[0] > 0 or (len(descr) == 0 and not include_seconds):
+ descr = descr + f'{int(minutes[0])}m '
+ if minutes[1] > 0 and include_seconds:
+ descr = descr + f'{int(minutes[1])}s'
return descr.strip()
+
+
+def describe_timedelta_briefly(delta: datetime.timedelta) -> str:
+ """
+ Describe a duration represented by a timedelta object.
+
+ >>> d = datetime.timedelta(1, 600)
+ >>> describe_timedelta_briefly(d)
+ '1d 10m'
+
+ """
+ return describe_duration_briefly(delta.total_seconds())
+
+
+if __name__ == '__main__':
+ import doctest
+ doctest.testmod()
projects / python_utils.git / blobdiff