Source code for schedule

"""
Python job scheduling for humans.

github.com/dbader/schedule

An in-process scheduler for periodic jobs that uses the builder pattern
for configuration. Schedule lets you run Python functions (or any other
callable) periodically at pre-determined intervals using a simple,
human-friendly syntax.

Inspired by Addam Wiggins' article "Rethinking Cron" [1] and the
"clockwork" Ruby module [2][3].

Features:
    - A simple to use API for scheduling jobs.
    - Very lightweight and no external dependencies.
    - Excellent test coverage.
    - Tested on Python 3.6, 3.7, 3.8, 3.9

Usage:
    >>> import schedule
    >>> import time

    >>> def job(message='stuff'):
    >>>     print("I'm working on:", message)

    >>> schedule.every(10).minutes.do(job)
    >>> schedule.every(5).to(10).days.do(job)
    >>> schedule.every().hour.do(job, message='things')
    >>> schedule.every().day.at("10:30").do(job)

    >>> while True:
    >>>     schedule.run_pending()
    >>>     time.sleep(1)

[1] https://adam.herokuapp.com/past/2010/4/13/rethinking_cron/
[2] https://github.com/Rykian/clockwork
[3] https://adam.herokuapp.com/past/2010/6/30/replace_cron_with_clockwork/
"""
from collections.abc import Hashable
import datetime
import functools
import logging
import random
import re
import time
from typing import Set, List, Optional, Callable, Union

logger = logging.getLogger("schedule")


class ScheduleError(Exception):
    """Base schedule exception"""

    pass


class ScheduleValueError(ScheduleError):
    """Base schedule value error"""

    pass


class IntervalError(ScheduleValueError):
    """An improper interval was used"""

    pass


[docs]class CancelJob(object): """ Can be returned from a job to unschedule itself. """ pass
[docs]class Scheduler(object): """ Objects instantiated by the :class:`Scheduler <Scheduler>` are factories to create jobs, keep record of scheduled jobs and handle their execution. """ def __init__(self) -> None: self.jobs: List[Job] = []
[docs] def run_pending(self) -> None: """ Run all jobs that are scheduled to run. Please note that it is *intended behavior that run_pending() does not run missed jobs*. For example, if you've registered a job that should run every minute and you only call run_pending() in one hour increments then your job won't be run 60 times in between but only once. """ runnable_jobs = (job for job in self.jobs if job.should_run) for job in sorted(runnable_jobs): self._run_job(job)
[docs] def run_all(self, delay_seconds: int = 0) -> None: """ Run all jobs regardless if they are scheduled to run or not. A delay of `delay` seconds is added between each job. This helps distribute system load generated by the jobs more evenly over time. :param delay_seconds: A delay added between every executed job """ logger.debug( "Running *all* %i jobs with %is delay in between", len(self.jobs), delay_seconds, ) for job in self.jobs[:]: self._run_job(job) time.sleep(delay_seconds)
[docs] def get_jobs(self, tag: Optional[Hashable] = None) -> List["Job"]: """ Gets scheduled jobs marked with the given tag, or all jobs if tag is omitted. :param tag: An identifier used to identify a subset of jobs to retrieve """ if tag is None: return self.jobs[:] else: return [job for job in self.jobs if tag in job.tags]
[docs] def clear(self, tag: Optional[Hashable] = None) -> None: """ Deletes scheduled jobs marked with the given tag, or all jobs if tag is omitted. :param tag: An identifier used to identify a subset of jobs to delete """ if tag is None: logger.debug("Deleting *all* jobs") del self.jobs[:] else: logger.debug('Deleting all jobs tagged "%s"', tag) self.jobs[:] = (job for job in self.jobs if tag not in job.tags)
[docs] def cancel_job(self, job: "Job") -> None: """ Delete a scheduled job. :param job: The job to be unscheduled """ try: logger.debug('Cancelling job "%s"', str(job)) self.jobs.remove(job) except ValueError: logger.debug('Cancelling not-scheduled job "%s"', str(job))
[docs] def every(self, interval: int = 1) -> "Job": """ Schedule a new periodic job. :param interval: A quantity of a certain time unit :return: An unconfigured :class:`Job <Job>` """ job = Job(interval, self) return job
def _run_job(self, job: "Job") -> None: ret = job.run() if isinstance(ret, CancelJob) or ret is CancelJob: self.cancel_job(job) @property def next_run(self) -> Optional[datetime.datetime]: """ Datetime when the next job should run. :return: A :class:`~datetime.datetime` object or None if no jobs scheduled """ if not self.jobs: return None return min(self.jobs).next_run @property def idle_seconds(self) -> Optional[float]: """ :return: Number of seconds until :meth:`next_run <Scheduler.next_run>` or None if no jobs are scheduled """ if not self.next_run: return None return (self.next_run - datetime.datetime.now()).total_seconds()
[docs]class Job(object): """ A periodic job as used by :class:`Scheduler`. :param interval: A quantity of a certain time unit :param scheduler: The :class:`Scheduler <Scheduler>` instance that this job will register itself with once it has been fully configured in :meth:`Job.do()`. Every job runs at a given fixed time interval that is defined by: * a :meth:`time unit <Job.second>` * a quantity of `time units` defined by `interval` A job is usually created and returned by :meth:`Scheduler.every` method, which also defines its `interval`. """ def __init__(self, interval: int, scheduler: Scheduler = None): self.interval: int = interval # pause interval * unit between runs self.latest: Optional[int] = None # upper limit to the interval self.job_func: Optional[functools.partial] = None # the job job_func to run # time units, e.g. 'minutes', 'hours', ... self.unit: Optional[str] = None # optional time at which this job runs self.at_time: Optional[datetime.time] = None # datetime of the last run self.last_run: Optional[datetime.datetime] = None # datetime of the next run self.next_run: Optional[datetime.datetime] = None # timedelta between runs, only valid for self.period: Optional[datetime.timedelta] = None # Specific day of the week to start on self.start_day: Optional[str] = None # optional time of final run self.cancel_after: Optional[datetime.datetime] = None self.tags: Set[Hashable] = set() # unique set of tags for the job self.scheduler: Optional[Scheduler] = scheduler # scheduler to register with def __lt__(self, other) -> bool: """ PeriodicJobs are sortable based on the scheduled time they run next. """ return self.next_run < other.next_run def __str__(self) -> str: if hasattr(self.job_func, "__name__"): job_func_name = self.job_func.__name__ # type: ignore else: job_func_name = repr(self.job_func) return ("Job(interval={}, unit={}, do={}, args={}, kwargs={})").format( self.interval, self.unit, job_func_name, "()" if self.job_func is None else self.job_func.args, "{}" if self.job_func is None else self.job_func.keywords, ) def __repr__(self): def format_time(t): return t.strftime("%Y-%m-%d %H:%M:%S") if t else "[never]" def is_repr(j): return not isinstance(j, Job) timestats = "(last run: %s, next run: %s)" % ( format_time(self.last_run), format_time(self.next_run), ) if hasattr(self.job_func, "__name__"): job_func_name = self.job_func.__name__ else: job_func_name = repr(self.job_func) args = [repr(x) if is_repr(x) else str(x) for x in self.job_func.args] kwargs = ["%s=%s" % (k, repr(v)) for k, v in self.job_func.keywords.items()] call_repr = job_func_name + "(" + ", ".join(args + kwargs) + ")" if self.at_time is not None: return "Every %s %s at %s do %s %s" % ( self.interval, self.unit[:-1] if self.interval == 1 else self.unit, self.at_time, call_repr, timestats, ) else: fmt = ( "Every %(interval)s " + ("to %(latest)s " if self.latest is not None else "") + "%(unit)s do %(call_repr)s %(timestats)s" ) return fmt % dict( interval=self.interval, latest=self.latest, unit=(self.unit[:-1] if self.interval == 1 else self.unit), call_repr=call_repr, timestats=timestats, ) @property def second(self): if self.interval != 1: raise IntervalError("Use seconds instead of second") return self.seconds @property def seconds(self): self.unit = "seconds" return self @property def minute(self): if self.interval != 1: raise IntervalError("Use minutes instead of minute") return self.minutes @property def minutes(self): self.unit = "minutes" return self @property def hour(self): if self.interval != 1: raise IntervalError("Use hours instead of hour") return self.hours @property def hours(self): self.unit = "hours" return self @property def day(self): if self.interval != 1: raise IntervalError("Use days instead of day") return self.days @property def days(self): self.unit = "days" return self @property def week(self): if self.interval != 1: raise IntervalError("Use weeks instead of week") return self.weeks @property def weeks(self): self.unit = "weeks" return self @property def monday(self): if self.interval != 1: raise IntervalError( "Scheduling .monday() jobs is only allowed for weekly jobs. " "Using .monday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "monday" return self.weeks @property def tuesday(self): if self.interval != 1: raise IntervalError( "Scheduling .tuesday() jobs is only allowed for weekly jobs. " "Using .tuesday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "tuesday" return self.weeks @property def wednesday(self): if self.interval != 1: raise IntervalError( "Scheduling .wednesday() jobs is only allowed for weekly jobs. " "Using .wednesday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "wednesday" return self.weeks @property def thursday(self): if self.interval != 1: raise IntervalError( "Scheduling .thursday() jobs is only allowed for weekly jobs. " "Using .thursday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "thursday" return self.weeks @property def friday(self): if self.interval != 1: raise IntervalError( "Scheduling .friday() jobs is only allowed for weekly jobs. " "Using .friday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "friday" return self.weeks @property def saturday(self): if self.interval != 1: raise IntervalError( "Scheduling .saturday() jobs is only allowed for weekly jobs. " "Using .saturday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "saturday" return self.weeks @property def sunday(self): if self.interval != 1: raise IntervalError( "Scheduling .sunday() jobs is only allowed for weekly jobs. " "Using .sunday() on a job scheduled to run every 2 or more weeks " "is not supported." ) self.start_day = "sunday" return self.weeks
[docs] def tag(self, *tags: Hashable): """ Tags the job with one or more unique identifiers. Tags must be hashable. Duplicate tags are discarded. :param tags: A unique list of ``Hashable`` tags. :return: The invoked job instance """ if not all(isinstance(tag, Hashable) for tag in tags): raise TypeError("Tags must be hashable") self.tags.update(tags) return self
[docs] def at(self, time_str): """ Specify a particular time that the job should be run at. :param time_str: A string in one of the following formats: - For daily jobs -> `HH:MM:SS` or `HH:MM` - For hourly jobs -> `MM:SS` or `:MM` - For minute jobs -> `:SS` The format must make sense given how often the job is repeating; for example, a job that repeats every minute should not be given a string in the form `HH:MM:SS`. The difference between `:MM` and :SS` is inferred from the selected time-unit (e.g. `every().hour.at(':30')` vs. `every().minute.at(':30')`). :return: The invoked job instance """ if self.unit not in ("days", "hours", "minutes") and not self.start_day: raise ScheduleValueError( "Invalid unit (valid units are `days`, `hours`, and `minutes`)" ) if not isinstance(time_str, str): raise TypeError("at() should be passed a string") if self.unit == "days" or self.start_day: if not re.match(r"^([0-2]\d:)?[0-5]\d:[0-5]\d$", time_str): raise ScheduleValueError( "Invalid time format for a daily job (valid format is HH:MM(:SS)?)" ) if self.unit == "hours": if not re.match(r"^([0-5]\d)?:[0-5]\d$", time_str): raise ScheduleValueError( "Invalid time format for an hourly job (valid format is (MM)?:SS)" ) if self.unit == "minutes": if not re.match(r"^:[0-5]\d$", time_str): raise ScheduleValueError( "Invalid time format for a minutely job (valid format is :SS)" ) time_values = time_str.split(":") hour: Union[str, int] minute: Union[str, int] second: Union[str, int] if len(time_values) == 3: hour, minute, second = time_values elif len(time_values) == 2 and self.unit == "minutes": hour = 0 minute = 0 _, second = time_values elif len(time_values) == 2 and self.unit == "hours" and len(time_values[0]): hour = 0 minute, second = time_values else: hour, minute = time_values second = 0 if self.unit == "days" or self.start_day: hour = int(hour) if not (0 <= hour <= 23): raise ScheduleValueError( "Invalid number of hours ({} is not between 0 and 23)" ) elif self.unit == "hours": hour = 0 elif self.unit == "minutes": hour = 0 minute = 0 minute = int(minute) second = int(second) self.at_time = datetime.time(hour, minute, second) return self
[docs] def to(self, latest: int): """ Schedule the job to run at an irregular (randomized) interval. The job's interval will randomly vary from the value given to `every` to `latest`. The range defined is inclusive on both ends. For example, `every(A).to(B).seconds` executes the job function every N seconds such that A <= N <= B. :param latest: Maximum interval between randomized job runs :return: The invoked job instance """ self.latest = latest return self
[docs] def until( self, until_time: Union[datetime.datetime, datetime.timedelta, datetime.time, str], ): """ Schedule job to run until the specified moment. The job is canceled whenever the next run is calculated and it turns out the next run is after the until_time. The job is also canceled right before it runs, if the current time is after until_time. This latter case can happen when the the job was scheduled to run before until_time, but runs after until_time. If until_time is a moment in the past, ScheduleValueError is thrown. :param until_time: A moment in the future representing the latest time a job can be run. If only a time is supplied, the date is set to today. The following formats are accepted: - datetime.datetime - datetime.timedelta - datetime.time - String in one of the following formats: "%Y-%m-%d %H:%M:%S", "%Y-%m-%d %H:%M", "%Y-%m-%d", "%H:%M:%S", "%H:%M" as defined by strptime() behaviour. If an invalid string format is passed, ScheduleValueError is thrown. :return: The invoked job instance """ if isinstance(until_time, datetime.datetime): self.cancel_after = until_time elif isinstance(until_time, datetime.timedelta): self.cancel_after = datetime.datetime.now() + until_time elif isinstance(until_time, datetime.time): self.cancel_after = datetime.datetime.combine( datetime.datetime.now(), until_time ) elif isinstance(until_time, str): cancel_after = self._decode_datetimestr( until_time, [ "%Y-%m-%d %H:%M:%S", "%Y-%m-%d %H:%M", "%Y-%m-%d", "%H:%M:%S", "%H:%M", ], ) if cancel_after is None: raise ScheduleValueError("Invalid string format for until()") if "-" not in until_time: # the until_time is a time-only format. Set the date to today now = datetime.datetime.now() cancel_after = cancel_after.replace( year=now.year, month=now.month, day=now.day ) self.cancel_after = cancel_after else: raise TypeError( "until() takes a string, datetime.datetime, datetime.timedelta, " "datetime.time parameter" ) if self.cancel_after < datetime.datetime.now(): raise ScheduleValueError( "Cannot schedule a job to run until a time in the past" ) return self
[docs] def do(self, job_func: Callable, *args, **kwargs): """ Specifies the job_func that should be called every time the job runs. Any additional arguments are passed on to job_func when the job runs. :param job_func: The function to be scheduled :return: The invoked job instance """ self.job_func = functools.partial(job_func, *args, **kwargs) functools.update_wrapper(self.job_func, job_func) self._schedule_next_run() if self.scheduler is None: raise ScheduleError( "Unable to a add job to schedule. " "Job is not associated with an scheduler" ) self.scheduler.jobs.append(self) return self
@property def should_run(self) -> bool: """ :return: ``True`` if the job should be run now. """ assert self.next_run is not None, "must run _schedule_next_run before" return datetime.datetime.now() >= self.next_run
[docs] def run(self): """ Run the job and immediately reschedule it. If the job's deadline is reached (configured using .until()), the job is not run and CancelJob is returned immediately. If the next scheduled run exceeds the job's deadline, CancelJob is returned after the execution. In this latter case CancelJob takes priority over any other returned value. :return: The return value returned by the `job_func`, or CancelJob if the job's deadline is reached. """ if self._is_overdue(datetime.datetime.now()): logger.debug("Cancelling job %s", self) return CancelJob logger.debug("Running job %s", self) ret = self.job_func() self.last_run = datetime.datetime.now() self._schedule_next_run() if self._is_overdue(self.next_run): logger.debug("Cancelling job %s", self) return CancelJob return ret
def _schedule_next_run(self) -> None: """ Compute the instant when this job should run next. """ if self.unit not in ("seconds", "minutes", "hours", "days", "weeks"): raise ScheduleValueError( "Invalid unit (valid units are `seconds`, `minutes`, `hours`, " "`days`, and `weeks`)" ) if self.latest is not None: if not (self.latest >= self.interval): raise ScheduleError("`latest` is greater than `interval`") interval = random.randint(self.interval, self.latest) else: interval = self.interval self.period = datetime.timedelta(**{self.unit: interval}) self.next_run = datetime.datetime.now() + self.period if self.start_day is not None: if self.unit != "weeks": raise ScheduleValueError("`unit` should be 'weeks'") weekdays = ( "monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday", ) if self.start_day not in weekdays: raise ScheduleValueError( "Invalid start day (valid start days are {})".format(weekdays) ) weekday = weekdays.index(self.start_day) days_ahead = weekday - self.next_run.weekday() if days_ahead <= 0: # Target day already happened this week days_ahead += 7 self.next_run += datetime.timedelta(days_ahead) - self.period if self.at_time is not None: if self.unit not in ("days", "hours", "minutes") and self.start_day is None: raise ScheduleValueError("Invalid unit without specifying start day") kwargs = {"second": self.at_time.second, "microsecond": 0} if self.unit == "days" or self.start_day is not None: kwargs["hour"] = self.at_time.hour if self.unit in ["days", "hours"] or self.start_day is not None: kwargs["minute"] = self.at_time.minute self.next_run = self.next_run.replace(**kwargs) # type: ignore # Make sure we run at the specified time *today* (or *this hour*) # as well. This accounts for when a job takes so long it finished # in the next period. if not self.last_run or (self.next_run - self.last_run) > self.period: now = datetime.datetime.now() if ( self.unit == "days" and self.at_time > now.time() and self.interval == 1 ): self.next_run = self.next_run - datetime.timedelta(days=1) elif self.unit == "hours" and ( self.at_time.minute > now.minute or ( self.at_time.minute == now.minute and self.at_time.second > now.second ) ): self.next_run = self.next_run - datetime.timedelta(hours=1) elif self.unit == "minutes" and self.at_time.second > now.second: self.next_run = self.next_run - datetime.timedelta(minutes=1) if self.start_day is not None and self.at_time is not None: # Let's see if we will still make that time we specified today if (self.next_run - datetime.datetime.now()).days >= 7: self.next_run -= self.period def _is_overdue(self, when: datetime.datetime): return self.cancel_after is not None and when > self.cancel_after def _decode_datetimestr( self, datetime_str: str, formats: List[str] ) -> Optional[datetime.datetime]: for f in formats: try: return datetime.datetime.strptime(datetime_str, f) except ValueError: pass return None
# The following methods are shortcuts for not having to # create a Scheduler instance: #: Default :class:`Scheduler <Scheduler>` object default_scheduler = Scheduler() #: Default :class:`Jobs <Job>` list jobs = default_scheduler.jobs # todo: should this be a copy, e.g. jobs()?
[docs]def every(interval: int = 1) -> Job: """Calls :meth:`every <Scheduler.every>` on the :data:`default scheduler instance <default_scheduler>`. """ return default_scheduler.every(interval)
[docs]def run_pending() -> None: """Calls :meth:`run_pending <Scheduler.run_pending>` on the :data:`default scheduler instance <default_scheduler>`. """ default_scheduler.run_pending()
[docs]def run_all(delay_seconds: int = 0) -> None: """Calls :meth:`run_all <Scheduler.run_all>` on the :data:`default scheduler instance <default_scheduler>`. """ default_scheduler.run_all(delay_seconds=delay_seconds)
[docs]def get_jobs(tag: Optional[Hashable] = None) -> List[Job]: """Calls :meth:`get_jobs <Scheduler.get_jobs>` on the :data:`default scheduler instance <default_scheduler>`. """ return default_scheduler.get_jobs(tag)
[docs]def clear(tag: Optional[Hashable] = None) -> None: """Calls :meth:`clear <Scheduler.clear>` on the :data:`default scheduler instance <default_scheduler>`. """ default_scheduler.clear(tag)
[docs]def cancel_job(job: Job) -> None: """Calls :meth:`cancel_job <Scheduler.cancel_job>` on the :data:`default scheduler instance <default_scheduler>`. """ default_scheduler.cancel_job(job)
[docs]def next_run() -> Optional[datetime.datetime]: """Calls :meth:`next_run <Scheduler.next_run>` on the :data:`default scheduler instance <default_scheduler>`. """ return default_scheduler.next_run
[docs]def idle_seconds() -> Optional[float]: """Calls :meth:`idle_seconds <Scheduler.idle_seconds>` on the :data:`default scheduler instance <default_scheduler>`. """ return default_scheduler.idle_seconds
def repeat(job, *args, **kwargs): """ Decorator to schedule a new periodic job. Any additional arguments are passed on to the decorated function when the job runs. :param job: a :class:`Jobs <Job>` """ def _schedule_decorator(decorated_function): job.do(decorated_function, *args, **kwargs) return decorated_function return _schedule_decorator