import asyncio
import dataclasses
from dataclasses import dataclass
from datetime import datetime, timedelta
from typing import Optional, Union
from .typing import WEEKDAYS, OptionType, SecondsTimedelta, WeekdayOptionType, WorkerCoroutine
from .utils import import_string, to_seconds
@dataclass
class Options:
month: OptionType
day: OptionType
weekday: WeekdayOptionType
hour: OptionType
minute: OptionType
second: OptionType
microsecond: int
def next_cron(
previous_dt: datetime,
*,
month: OptionType = None,
day: OptionType = None,
weekday: WeekdayOptionType = None,
hour: OptionType = None,
minute: OptionType = None,
second: OptionType = 0,
microsecond: int = 123_456,
) -> datetime:
"""
Find the next datetime matching the given parameters.
"""
dt = previous_dt + timedelta(seconds=1)
if isinstance(weekday, str):
weekday = WEEKDAYS.index(weekday.lower())
options = Options(
month=month, day=day, weekday=weekday, hour=hour, minute=minute, second=second, microsecond=microsecond
)
while True:
next_dt = _get_next_dt(dt, options)
# print(dt, next_dt)
if next_dt is None:
return dt
dt = next_dt
def _get_next_dt(dt_: datetime, options: Options) -> Optional[datetime]: # noqa: C901
for field, v in dataclasses.asdict(options).items():
if v is None:
continue
if field == 'weekday':
next_v = dt_.weekday()
else:
next_v = getattr(dt_, field)
if isinstance(v, int):
mismatch = next_v != v
elif isinstance(v, (set, list, tuple)):
mismatch = next_v not in v
else:
raise RuntimeError(v)
# print(field, v, next_v, mismatch)
if mismatch:
micro = max(dt_.microsecond - options.microsecond, 0)
if field == 'month':
if dt_.month == 12:
return datetime(dt_.year + 1, 1, 1, tzinfo=dt_.tzinfo)
else:
return datetime(dt_.year, dt_.month + 1, 1, tzinfo=dt_.tzinfo)
elif field in ('day', 'weekday'):
return (
dt_
+ timedelta(days=1)
- timedelta(hours=dt_.hour, minutes=dt_.minute, seconds=dt_.second, microseconds=micro)
)
elif field == 'hour':
return dt_ + timedelta(hours=1) - timedelta(minutes=dt_.minute, seconds=dt_.second, microseconds=micro)
elif field == 'minute':
return dt_ + timedelta(minutes=1) - timedelta(seconds=dt_.second, microseconds=micro)
elif field == 'second':
return dt_ + timedelta(seconds=1) - timedelta(microseconds=micro)
else:
if field != 'microsecond':
raise RuntimeError(field)
return dt_ + timedelta(microseconds=options.microsecond - dt_.microsecond)
return None
@dataclass
class CronJob:
name: str
coroutine: WorkerCoroutine
month: OptionType
day: OptionType
weekday: WeekdayOptionType
hour: OptionType
minute: OptionType
second: OptionType
microsecond: int
run_at_startup: bool
unique: bool
job_id: Optional[str]
timeout_s: Optional[float]
keep_result_s: Optional[float]
keep_result_forever: Optional[bool]
max_tries: Optional[int]
next_run: Optional[datetime] = None
def calculate_next(self, prev_run: datetime) -> None:
self.next_run = next_cron(
prev_run,
month=self.month,
day=self.day,
weekday=self.weekday,
hour=self.hour,
minute=self.minute,
second=self.second,
microsecond=self.microsecond,
)
def __repr__(self) -> str:
return '<CronJob {}>'.format(' '.join(f'{k}={v}' for k, v in self.__dict__.items()))
[docs]def cron(
coroutine: Union[str, WorkerCoroutine],
*,
name: Optional[str] = None,
month: OptionType = None,
day: OptionType = None,
weekday: WeekdayOptionType = None,
hour: OptionType = None,
minute: OptionType = None,
second: OptionType = 0,
microsecond: int = 123_456,
run_at_startup: bool = False,
unique: bool = True,
job_id: Optional[str] = None,
timeout: Optional[SecondsTimedelta] = None,
keep_result: Optional[float] = 0,
keep_result_forever: Optional[bool] = False,
max_tries: Optional[int] = 1,
) -> CronJob:
"""
Create a cron job, eg. it should be executed at specific times.
Workers will enqueue this job at or just after the set times. If ``unique`` is true (the default) the
job will only be run once even if multiple workers are running.
:param coroutine: coroutine function to run
:param name: name of the job, if None, the name of the coroutine is used
:param month: month(s) to run the job on, 1 - 12
:param day: day(s) to run the job on, 1 - 31
:param weekday: week day(s) to run the job on, 0 - 6 or mon - sun
:param hour: hour(s) to run the job on, 0 - 23
:param minute: minute(s) to run the job on, 0 - 59
:param second: second(s) to run the job on, 0 - 59
:param microsecond: microsecond(s) to run the job on,
defaults to 123456 as the world is busier at the top of a second, 0 - 1e6
:param run_at_startup: whether to run as worker starts
:param unique: whether the job should only be executed once at each time (useful if you have multiple workers)
:param job_id: ID of the job, can be used to enforce job uniqueness, spanning multiple cron schedules
:param timeout: job timeout
:param keep_result: how long to keep the result for
:param keep_result_forever: whether to keep results forever
:param max_tries: maximum number of tries for the job
"""
if isinstance(coroutine, str):
name = name or 'cron:' + coroutine
coroutine_: WorkerCoroutine = import_string(coroutine)
else:
coroutine_ = coroutine
if not asyncio.iscoroutinefunction(coroutine_):
raise RuntimeError(f'{coroutine_} is not a coroutine function')
timeout = to_seconds(timeout)
keep_result = to_seconds(keep_result)
return CronJob(
name or 'cron:' + coroutine_.__qualname__,
coroutine_,
month,
day,
weekday,
hour,
minute,
second,
microsecond,
run_at_startup,
unique,
job_id,
timeout,
keep_result,
keep_result_forever,
max_tries,
)
