1 """Module that provides a cron-like task scheduler.
2
3 This task scheduler is designed to be used from inside your own program.
4 You can schedule Python functions to be called at specific intervals or
5 days. It uses the standard 'sched' module for the actual task scheduling,
6 but provides much more:
7
8 * repeated tasks (at intervals, or on specific days)
9 * error handling (exceptions in tasks don't kill the scheduler)
10 * optional to run scheduler in its own thread or separate process
11 * optional to run a task in its own thread or separate process
12
13 If the threading module is available, you can use the various Threaded
14 variants of the scheduler and associated tasks. If threading is not
15 available, you could still use the forked variants. If fork is also
16 not available, all processing is done in a single process, sequentially.
17
18 There are three Scheduler classes:
19
20 Scheduler ThreadedScheduler ForkedScheduler
21
22 You usually add new tasks to a scheduler using the add_interval_task or
23 add_daytime_task methods, with the appropriate processmethod argument
24 to select sequential, threaded or forked processing. NOTE: it is impossible
25 to add new tasks to a ForkedScheduler, after the scheduler has been started!
26 For more control you can use one of the following Task classes
27 and use schedule_task or schedule_task_abs:
28
29 IntervalTask ThreadedIntervalTask ForkedIntervalTask
30 SingleTask ThreadedSingleTask ForkedSingleTask
31 WeekdayTask ThreadedWeekdayTask ForkedWeekdayTask
32 CronLikeTask ThreadedCronLikeTask ForkedCronLikeTask
33
34 Kronos is the Greek god of time. Kronos scheduler (c) by Irmen de Jong.
35
36 This module is based on the Kronos scheduler by Irmen de Jong, but has been
37 modified to better fit within TurboGears. Vince Spicer and Mathieu Bridon have
38 contributed some additions and improvements such as cron-like tasks. Some fixes
39 have been made to make it work on Python 2.6 (adaptations sched module changes).
40
41 """
42
43 __version__ = '2.0'
44
45 __all__ = [
46
47 'ForkedIntervalTask',
48 'ForkedMonthdayTask',
49 'ForkedScheduler',
50 'ForkedSingleTask',
51 'ForkedTaskMixin',
52 'ForkedWeekdayTask',
53 'IntervalTask',
54 'MonthdayTask',
55 'Scheduler',
56 'SingleTask',
57 'Task',
58 'ThreadedIntervalTask',
59 'ThreadedMonthdayTask',
60 'ThreadedScheduler',
61 'ThreadedSingleTask',
62 'ThreadedTaskMixin',
63 'ThreadedWeekdayTask',
64 'WeekdayTask',
65 'add_interval_task',
66 'add_monthday_task',
67 'add_single_task',
68 'add_weekday_task',
69 'cancel',
70 'method',
71 ]
72
73 import os
74 import sys
75 import sched
76 import datetime
77 import time
78 import logging
79 import weakref
80 import atexit
81
82 try:
83 from dateutil import rrule
84 except ImportError:
85 rrule = None
86
87 from turbogears.util import Enum
88
89 log = logging.getLogger('turbogears.scheduler')
90
91 method = Enum('sequential', 'forked', 'threaded')
92
93
94
95 MINUTE_BOUNDS = (0, 59)
96 HOUR_BOUNDS = (0, 23)
97 DOM_BOUNDS = (1, 31)
98 MONTH_BOUNDS = (1, 12)
99 DOW_BOUNDS = (0, 7)
100
101
102
103 MONTH_MAPPING = {
104 'jan': 1, 'feb': 2, 'mar': 3, 'apr': 4, 'may': 5, 'jun': 6,
105 'jul': 7, 'aug': 8, 'sep': 9, 'oct': 10, 'nov': 11, 'dec': 12}
106 DOW_MAPPING = {
107 'sun': 0, 'mon': 1, 'tue': 2, 'wed': 3, 'thu': 4, 'fri': 5, 'sat': 6}
108
109
111 """The Scheduler itself."""
112
114 self.running = True
115 self.sched = sched.scheduler(time.time, self.__delayfunc)
116 self.tasks = dict()
117
119 """The delay function for the sched.scheduler.
120
121 This delay function is basically a time.sleep() that is divided up,
122 so that we can check the self.running flag while delaying.
123 There is an additional check in here to ensure that the top item of
124 the queue hasn't changed.
125
126 """
127 period = 5
128 if delay < period:
129 time.sleep(delay)
130 else:
131 toptime = self._getqueuetoptime()
132 endtime = time.time() + delay
133 stoptime = endtime - period
134 while self.running and stoptime > time.time():
135 self._acquire_lock()
136 try:
137 if not self._getqueuetoptime() == toptime:
138 break
139 finally:
140 self._release_lock()
141 time.sleep(period)
142 if not self.running or self._getqueuetoptime() != toptime:
143 return
144 now = time.time()
145 if endtime > now:
146 time.sleep(endtime - now)
147
150
153
154 - def add_interval_task(self, action, taskname, initialdelay, interval,
155 processmethod, args, kw):
156 """Add a new Interval Task to the schedule.
157
158 A very short initialdelay or one of zero cannot be honored, you will
159 see a slight delay before the task is first executed. This is because
160 the scheduler needs to pick it up in its loop.
161
162 """
163 if initialdelay < 0 or interval < 1:
164 raise ValueError("Delay or interval must be >0")
165
166 if processmethod == method.sequential:
167 TaskClass = IntervalTask
168 elif processmethod == method.threaded:
169 TaskClass = ThreadedIntervalTask
170 elif processmethod == method.forked:
171 TaskClass = ForkedIntervalTask
172 else:
173 raise ValueError("Invalid processmethod")
174 if not args:
175 args = []
176 if not kw:
177 kw = {}
178 if self.running:
179 self._acquire_lock()
180 try:
181 if taskname in self.tasks:
182 raise ValueError(
183 "A task with the name %s already exists" % taskname)
184 finally:
185 self._release_lock()
186 else:
187 if taskname in self.tasks:
188 raise ValueError(
189 "A task with the name %s already exists" % taskname)
190 task = TaskClass(taskname, interval, action, args, kw)
191 self.schedule_task(task, initialdelay)
192 return task
193
194 - def add_single_task(self, action, taskname, initialdelay, processmethod,
195 args, kw):
196 """Add a new task to the scheduler that will only be executed once."""
197 if initialdelay < 0:
198 raise ValueError("Delay must be >0")
199
200 if processmethod == method.sequential:
201 TaskClass = SingleTask
202 elif processmethod == method.threaded:
203 TaskClass = ThreadedSingleTask
204 elif processmethod == method.forked:
205 TaskClass = ForkedSingleTask
206 else:
207 raise ValueError("Invalid processmethod")
208 if not args:
209 args = []
210 if not kw:
211 kw = {}
212 if self.running:
213 self._acquire_lock()
214 try:
215 if taskname in self.tasks:
216 raise ValueError(
217 "A task with the name %s already exists" % taskname)
218 finally:
219 self._release_lock()
220 else:
221 if taskname in self.tasks:
222 raise ValueError(
223 "A task with the name %s already exists" % taskname)
224 task = TaskClass(taskname, action, args, kw)
225 self.schedule_task(task, initialdelay)
226 return task
227
228 - def add_daytime_task(self, action, taskname, weekdays, monthdays, timeonday,
229 processmethod, args, kw):
230 """Add a new Day Task (Weekday or Monthday) to the schedule."""
231 if weekdays and monthdays:
232 raise ValueError("You can only specify weekdays or monthdays, "
233 "not both")
234 if not args:
235 args = []
236 if not kw:
237 kw = {}
238 if weekdays:
239
240
241 if processmethod == method.sequential:
242 TaskClass = WeekdayTask
243 elif processmethod == method.threaded:
244 TaskClass = ThreadedWeekdayTask
245 elif processmethod == method.forked:
246 TaskClass = ForkedWeekdayTask
247 else:
248 raise ValueError("Invalid processmethod")
249 if self.running:
250 self._acquire_lock()
251 try:
252 if taskname in self.tasks:
253 raise ValueError(
254 "A task with the name %s already exists" % taskname)
255 finally:
256 self._release_lock()
257 else:
258 if taskname in self.tasks:
259 raise ValueError(
260 "A task with the name %s already exists" % taskname)
261 task = TaskClass(taskname, weekdays, timeonday, action, args, kw)
262 if monthdays:
263
264
265 if processmethod == method.sequential:
266 TaskClass = MonthdayTask
267 elif processmethod == method.threaded:
268 TaskClass = ThreadedMonthdayTask
269 elif processmethod == method.forked:
270 TaskClass = ForkedMonthdayTask
271 else:
272 raise ValueError("Invalid processmethod")
273 if self.running:
274 self._acquire_lock()
275 try:
276 if taskname in self.tasks:
277 raise ValueError(
278 "A task with the name %s already exists" % taskname)
279 finally:
280 self._release_lock()
281 else:
282 if taskname in self.tasks:
283 raise ValueError(
284 "A task with the name %s already exists" % taskname)
285 task = TaskClass(taskname, monthdays, timeonday, action, args, kw)
286 firsttime = task.get_schedule_time(True)
287 self.schedule_task_abs(task, firsttime)
288 return task
289
292 """Add a new Cron-like Task to the schedule."""
293 if not args:
294 args = []
295 if not kw:
296 kw = {}
297 if processmethod == method.sequential:
298 TaskClass = CronLikeTask
299 elif processmethod == method.threaded:
300 TaskClass = ThreadedCronLikeTask
301 elif processmethod == method.forked:
302 TaskClass = ForkedCronLikeTask
303 else:
304 raise ValueError("Invalid processmethod")
305 if self.running:
306 self._acquire_lock()
307 try:
308 if taskname in self.tasks:
309 raise ValueError(
310 "A task with the name %s already exists" % taskname)
311 finally:
312 self._release_lock()
313 else:
314 if taskname in self.tasks:
315 raise ValueError(
316 "A task with the name %s already exists" % taskname)
317 task = TaskClass(taskname, action, cron_str, args, kw)
318 firsttime = task.get_schedule_time()
319 self.schedule_task_abs(task, firsttime)
320 return task
321
323 """Add a new task to the scheduler with the given delay (seconds).
324
325 Low-level method for internal use.
326
327 """
328 if self.running:
329
330 self._acquire_lock()
331 try:
332 task.event = self.sched.enter(
333 delay, 0, task, (weakref.ref(self),))
334 if task.name:
335 self.tasks[task.name] = task
336 else:
337 log.debug("task %s doesn't have a name" % task)
338 finally:
339 self._release_lock()
340 else:
341 task.event = self.sched.enter(
342 delay, 0, task, (weakref.ref(self),))
343 if task.name:
344 self.tasks[task.name] = task
345 else:
346 log.debug("task %s doesn't have a name" % task)
347
349 """Add a new task to the scheduler for the given absolute time value.
350
351 Low-level method for internal use.
352
353 """
354 if self.running:
355
356 self._acquire_lock()
357 try:
358 task.event = self.sched.enterabs(
359 abstime, 0, task, (weakref.ref(self),))
360 if task.name:
361 self.tasks[task.name] = task
362 else:
363 log.debug("task %s doesn't have a name" % task)
364 finally:
365 self._release_lock()
366 else:
367 task.event = self.sched.enterabs(
368 abstime, 0, task, (weakref.ref(self),))
369 if task.name:
370 self.tasks[task.name] = task
371 else:
372 log.debug("task %s doesn't have a name" % task)
373
375 """Start the scheduler."""
376 self._run()
377
379 """Remove all pending tasks and stop the scheduler."""
380 self.running = False
381 self._clearschedqueue()
382
384 """Cancel given scheduled task."""
385 if self.running:
386 self._acquire_lock()
387 try:
388 self.sched.cancel(task.event)
389 if task.name and task.name in self.tasks:
390 del self.tasks[task.name]
391 finally:
392 self._release_lock()
393 else:
394 self.sched.cancel(task.event)
395 if task.name and task.name in self.tasks:
396 del self.tasks[task.name]
397
398 - def rename(self, taskname, newname):
399 """Rename a scheduled task."""
400 if taskname and taskname in self.tasks:
401 task = self.tasks.pop(taskname)
402 task.name = newname
403 self.tasks[newname] = task
404
405 if sys.version_info >= (2, 6):
406
408 if len(self.sched._queue):
409 return self.sched._queue[0].time
411 self.sched._queue[:] = []
412 else:
413
415 if len(self.sched.queue) and len(self.sched.queue[0]):
416 return self.sched.queue[0][0]
418 self.sched.queue[:] = []
419
421 """Low-level run method to do the actual scheduling loop."""
422 period = 0
423 while self.running:
424 try:
425 self.sched.run()
426 except Exception:
427 log.error("ERROR DURING SCHEDULER EXECUTION", exc_info=1)
428
429 if self.running:
430 if period < 5:
431 period += 0.25
432 time.sleep(period)
433
434
435 -class Task (object):
436 """Abstract base class of all scheduler tasks"""
437
438 - def __init__(self, name, action, args, kw):
444
446 """Execute the task action in the scheduler's thread."""
447 try:
448 self.execute()
449 except Exception:
450 self.handle_exception()
451 self.reschedule(schedulerref())
452
454 """This method should be defined in one of the sub classes."""
455 raise NotImplementedError("You're using the abstract base class 'Task',"
456 " use a concrete class instead")
457
459 """Execute the actual task."""
460 self.action(*self.args, **self.kw)
461
463 """Handle any exception that occurred during task execution. """
464 log.error("ERROR DURING TASK EXECUTION", exc_info=1)
465
466
468 """A task that only runs once."""
469
472
473
475 """A repeated task that occurs at certain intervals (in seconds)."""
476
477 - def __init__(self, name, interval, action, args=None, kw=None):
480
485
486
488 """A mixin class that contains the reschedule logic for the DayTasks."""
489
491 self.timeonday = timeonday
492
494 """Calculate the time value at which this task is to be scheduled."""
495 now = list(time.localtime())
496 if today:
497
498 if (now[3], now[4]) >= self.timeonday:
499
500 now[2] += 1
501 else:
502
503 now[2] += 1
504
505 now[3], now[4] = self.timeonday
506
507 now[5] = 0
508 return time.mktime(now)
509
511 """Reschedule this task according to the daytime for the task.
512
513 The task is scheduled for tomorrow, for the given daytime.
514
515 """
516
517
518 if scheduler.running:
519 abstime = self.get_schedule_time(False)
520 scheduler.schedule_task_abs(self, abstime)
521
522
524 """A task that is run on a given weekday.
525
526 The task is called at specific days in a week (1-7), at a fixed time
527 on the day.
528
529 """
530
531 - def __init__(self, name, weekdays, timeonday, action, args=None, kw=None):
532 if type(timeonday) not in (list, tuple) or len(timeonday) != 2:
533 raise TypeError("timeonday must be a 2-tuple (hour,minute)")
534 if type(weekdays) not in (list, tuple):
535 raise TypeError("weekdays must be a sequence of weekday numbers "
536 "1-7 (1 is Monday)")
537 DayTaskRescheduler.__init__(self, timeonday)
538 Task.__init__(self, name, action, args, kw)
539 self.days = weekdays
540
542
543
544 weekday = time.localtime().tm_wday + 1
545 if weekday in self.days:
546 self.action(*self.args, **self.kw)
547
548
550 """A task that is run on a given day every month.
551
552 The task is called at specific days in a month (1-31), at a fixed
553 time on the day.
554
555 """
556
557 - def __init__(self, name, monthdays, timeonday, action, args=None, kw=None):
558 if type(timeonday) not in (list, tuple) or len(timeonday) != 2:
559 raise TypeError("timeonday must be a 2-tuple (hour,minute)")
560 if type(monthdays) not in (list, tuple):
561 raise TypeError("monthdays must be a sequence of monthdays numbers "
562 "1-31")
563 DayTaskRescheduler.__init__(self, timeonday)
564 Task.__init__(self, name, action, args, kw)
565 self.days = monthdays
566
568
569
570 if time.localtime().tm_mday in self.days:
571 self.action(*self.args, **self.kw)
572
573
575 """A task that is scheduled based on a cron-like string.
576
577 A cron string is composed of **five** time and date fields,
578 **separated by spaces**.
579
580 Note: Tasks are executed when **all** the time and date fields match
581 the current time. This is an important difference with the UNIX cron.
582
583 The time and date fields are:
584
585 ============= ==================================
586 field allowed values
587 ============= ==================================
588 minute 0-59
589 hour 0-23
590 day of month 1-31
591 month 1-12 (or names, see below)
592 day of week 0-7 (0 or 7 is Sun, or use names)
593 ============= ==================================
594
595 A field may be an **asterisk** (``*``), which always stands for
596 *first-last*.
597
598 **Ranges** of numbers are allowed. Ranges are two numbers separated with
599 a hyphen. The specified range is inclusive. For example, ``8-11`` for
600 an "hours" entry specifies *execution at hours 8, 9, 10 and 11*.
601
602 **Lists** are allowed. A list is a set of numbers (or ranges) separated
603 by commas. Examples: ``1,2,5,9``, ``0-4,8-12``.
604
605 **Step values** can be used in conjunction with ranges. Following a
606 range with ``/<number>`` specifies skips of the number's value through
607 the range. For example,``0-23/2`` can be used in the "hours" field to
608 specify task execution *every other hour* (the alternative in the V7
609 standard is ``0,2,4,6,8,10,12,14,16,18,20,22``). Steps are also
610 permitted after an asterisk, so if you want to say *every two hours*,
611 just use ``*/2``.
612
613 **Names** can also be used for the "month" and "day of week" fields. Use
614 the first three letters of the particular day or month (case doesn't
615 matter). Ranges of mixed names and integer are not permitted.
616
617 """
618
619 - def __init__(self, name, action, cron_str, args=None, kw=None):
620 """Initialize the task."""
621 Task.__init__(self, name, action, args, kw)
622
623 if not rrule:
624 raise ImportError("The dateutil package must be installed"
625 " if you want to use cron-like tasks.")
626
627 self.cron_str = cron_str
628 try:
629 min_str, hour_str, dom_str, month_str, dow_str = cron_str.split()
630 except:
631 raise ValueError("Invalid value: %s" % cron_str)
632
633 self.minutes = self.__process_str(min_str, MINUTE_BOUNDS)
634 self.hours = self.__process_str(hour_str, HOUR_BOUNDS)
635 self.doms = self.__process_str(dom_str, DOM_BOUNDS)
636 self.months = self.__process_str(month_str, MONTH_BOUNDS,
637 mapping=MONTH_MAPPING)
638
639
640
641
642
643
644
645
646 self.dows = list(set([ (dow - 1) % 7
647 for dow in self.__process_str(dow_str,
648 DOW_BOUNDS, mapping=DOW_MAPPING) ]))
649 self.dows.sort()
650
652 """Transforms a field of the cron-like string into a list.
653
654 @param time_str: a field in the cron-like string
655 @type time_str: string
656
657 @param bounds: the acceptable limits for this field
658 @type bounds: 2-tuple of integers
659
660 @param mapping: the mapping between names and integer values
661 @type mapping: dict
662
663 """
664 freq = 1
665 if '/' in time_str:
666 try:
667 time_str, freq = time_str.split('/')
668 freq = int(freq)
669 except:
670 raise ValueError("Invalid value: '%s'" % time_str)
671
672 if time_str == '*':
673 result = range(bounds[0], bounds[1] + 1)
674 return result[::freq]
675
676 result = list()
677
678 for item in time_str.split(','):
679 if '-' not in item:
680
681 try:
682 time = int(item)
683 except:
684 if mapping and item.lower() in mapping:
685 time = mapping[item.lower()]
686 else:
687 raise ValueError("Invalid value: '%s'" % time_str)
688
689 if time < bounds[0] or time > bounds [1]:
690 raise ValueError("Invalid value: '%s'" % time_str)
691
692 result.append(time)
693 else:
694
695 try:
696 interval_low, interval_high = item.split('-')
697 except:
698
699 raise ValueError("Invalid value: '%s'" % time_str)
700
701 try:
702
703 time_low = int(interval_low)
704 time_high = int(interval_high)
705 except:
706 if (mapping and interval_low.lower() in mapping
707 and interval_high.lower() in mapping):
708
709 time_low = mapping[interval_low.lower()]
710 time_high = mapping[interval_high.lower()]
711 else:
712 raise ValueError("Invalid value: '%s'" % time_str)
713
714 if time_low < bounds[0] or time_high > bounds [1]:
715 raise ValueError("Invalid value: '%s'" % time_str)
716
717 result.extend(range(time_low, time_high + 1))
718
719
720 return result[::freq]
721
723 """Determine the next execution time of the task."""
724 now = datetime.datetime.now()
725
726
727
728
729
730
731
732 now += datetime.timedelta(seconds=1)
733
734 next_time = list(rrule.rrule(rrule.SECONDLY, count=1, bysecond=0,
735 byminute=self.minutes, byhour=self.hours,
736 bymonthday=self.doms, bymonth=self.months, byweekday=self.dows,
737 dtstart=now)[0].timetuple())
738
739 return time.mktime(next_time)
740
742 """Reschedule this task according to its cron-like string."""
743 if scheduler.running:
744 abstime = self.get_schedule_time()
745 scheduler.schedule_task_abs(self, abstime)
746
747
748 try:
749 import threading
750
752 """A Scheduler that runs in its own thread."""
753
755 Scheduler.__init__(self)
756
757 self.thread = None
758 self._lock = threading.Lock()
759
761 """Splice off a thread in which the scheduler will run."""
762 self.thread = threading.Thread(target=self._run)
763 self.thread.setDaemon(True)
764 self.thread.start()
765
767 """Stop the scheduler and wait for the thread to finish."""
768 Scheduler.stop(self)
769 try:
770 self.thread.join()
771 except AttributeError:
772 pass
773
775 """Lock the thread's task queue."""
776 self._lock.acquire()
777
779 """Release the lock on the thread's task queue."""
780 self._lock.release()
781
782
784 """A mixin class to make a Task execute in a separate thread."""
785
790
792 """
793 This method is run within its own thread, so we have to
794 do the execute() call and exception handling here.
795 """
796 try:
797 self.execute()
798 except Exception:
799 self.handle_exception()
800
802 """Interval Task that executes in its own thread."""
803 pass
804
806 """Single Task that executes in its own thread."""
807 pass
808
810 """Weekday Task that executes in its own thread."""
811 pass
812
814 """Monthday Task that executes in its own thread."""
815 pass
816
818 """Cron-like Task that executes in its own thread."""
819 pass
820
821 except ImportError:
822
823 pass
824
825
826 if hasattr(os, 'fork'):
827 import signal
828
830 """A Scheduler that runs in its own forked process."""
831
833 if hasattr(self, 'childpid'):
834 os.kill(self.childpid, signal.SIGKILL)
835
837 """Fork off a new process in which the scheduler will run."""
838 pid = os.fork()
839 if pid == 0:
840
841 signal.signal(signal.SIGUSR1, self.signalhandler)
842 self._run()
843 os._exit(0)
844 else:
845
846 self.childpid = pid
847
848 del self.sched
849
851 """Stop the scheduler and wait for the process to finish."""
852 os.kill(self.childpid, signal.SIGUSR1)
853 os.waitpid(self.childpid, 0)
854
857
858
860 """A mixin class to make a Task execute in a separate process."""
861
863 """Execute the task action in its own process."""
864 pid = os.fork()
865 if pid == 0:
866
867 try:
868 self.execute()
869 except Exception:
870 self.handle_exception()
871 os._exit(0)
872 else:
873
874 self.reschedule(schedulerref())
875
876
878 """Interval Task that executes in its own process."""
879 pass
880
882 """Single Task that executes in its own process."""
883 pass
884
886 """Weekday Task that executes in its own process."""
887 pass
888
890 """Monthday Task that executes in its own process."""
891 pass
892
894 """Cron-like Task that executes in its own process."""
895 pass
896
897
898 _scheduler_instance = None
899
919
920
922 """Start the scheduler and register shutdown at exit."""
923 log.info("Starting the scheduler...")
924 si = _get_scheduler()
925 si.start()
926 atexit.register(_stop_scheduler)
927 return si
928
929
931 """Stop the scheduler."""
932 log.info("Shutting down the scheduler...")
933 if not _scheduler_instance:
934 return
935 si = _get_scheduler()
936 si.stop()
937
938
939 -def add_interval_task(action, interval, args=None, kw=None,
940 initialdelay=0, processmethod=method.threaded, taskname=None):
941 """Add an interval task to the scheduler.
942
943 Pass in initialdelay with a number of seconds to wait before running and
944 an interval with the number of seconds between runs.
945
946 For example, an initialdelay of 600 and interval of 60 would mean
947 "start running after 10 minutes and run every 1 minute after that".
948
949 @param interval: The interval in seconds between executing the action
950 @param initaldelay: the initial delay before starting execution
951
952 @param action: The callable that will be called at the time you request
953 @param args: Tuple of positional parameters to pass to the action
954 @param kw: Keyword arguments to pass to the action
955 @param taskname: Tasks can have a name (stored in task.name), which can
956 help if you're trying to keep track of many tasks.
957 @param precessmethod: By default, each task will be run in a new thread.
958 You can also pass in turbogears.scheduler.method.sequential or
959 turbogears.scheduler.method.forked.
960
961 """
962 si = _get_scheduler()
963 return si.add_interval_task(action=action, interval=interval, args=args,
964 kw=kw, initialdelay=initialdelay, processmethod=processmethod,
965 taskname=taskname)
966
967
968 -def add_single_task(action, args=None, kw=None,
969 initialdelay=0, processmethod=method.threaded, taskname=None):
970 """Add a single task to the scheduler.
971
972 Runs a task once. Pass in ``initialdelay`` with a number of seconds
973 to wait before running.
974
975 @param initaldelay: the initial delay before starting execution
976
977 @param action: The callable that will be called at the time you request
978 @param args: Tuple of positional parameters to pass to the action
979 @param kw: Keyword arguments to pass to the action
980 @param taskname: Tasks can have a name (stored in task.name), which can
981 help if you're trying to keep track of many tasks.
982 @param precessmethod: By default, each task will be run in a new thread.
983 You can also pass in turbogears.scheduler.method.sequential or
984 turbogears.scheduler.method.forked.
985
986 """
987 si = _get_scheduler()
988 return si.add_single_task(action=action, args=args, kw=kw,
989 initialdelay=initialdelay, processmethod=processmethod,
990 taskname=taskname)
991
992
993 -def add_weekday_task(action, weekdays, timeonday, args=None, kw=None,
994 processmethod=method.threaded, taskname=None):
995 """Add a weekday task to the scheduler.
996
997 Runs on certain days of the week. Pass in a list or tuple of weekdays
998 from 1-7 (where 1 is Monday). Additionally, you need to pass in
999 timeonday which is the time of day to run. timeonday should be a tuple
1000 with (hour, minute).
1001
1002 @param weekdays: list ot tuple of weekdays to execute action
1003 @param timeonday: tuple (hour, minute), to run on weekday
1004
1005 @param action: The callable that will be called at the time you request
1006 @param args: Tuple of positional parameters to pass to the action
1007 @param kw: Keyword arguments to pass to the action
1008 @param taskname: Tasks can have a name (stored in task.name), which can
1009 help if you're trying to keep track of many tasks.
1010 @param precessmethod: By default, each task will be run in a new thread.
1011 You can also pass in turbogears.scheduler.method.sequential or
1012 turbogears.scheduler.method.forked.
1013
1014 """
1015 si = _get_scheduler()
1016 return si.add_daytime_task(action=action, taskname=taskname,
1017 weekdays=weekdays, monthdays=None, timeonday=timeonday,
1018 processmethod=processmethod, args=args, kw=kw)
1019
1020 add_weekly_task = add_weekday_task
1021
1022
1023 -def add_monthday_task(action, monthdays, timeonday, args=None, kw=None,
1024 processmethod=method.threaded, taskname=None):
1025 """Add a monthly task to the scheduler.
1026
1027 Runs on certain days of the month. Pass in a list or tuple of monthdays
1028 from 1-31, import and also pass in timeonday which is an (hour, minute)
1029 tuple of the time of day to run the task.
1030
1031 @param monthdays: list ot tuple of monthdays to execute action
1032 @param timeonday: tuple (hour, minute), to run on monthday
1033
1034 @param action: The callable that will be called at the time you request
1035 @param args: Tuple of positional parameters to pass to the action
1036 @param kw: Keyword arguments to pass to the action
1037 @param taskname: Tasks can have a name (stored in task.name), which can
1038 help if you're trying to keep track of many tasks.
1039 @param precessmethod: By default, each task will be run in a new thread.
1040 You can also pass in turbogears.scheduler.method.sequential or
1041 turbogears.scheduler.method.forked.
1042
1043 """
1044 si = _get_scheduler()
1045 return si.add_daytime_task(action=action, taskname=taskname,
1046 weekdays=None, monthdays=monthdays, timeonday=timeonday,
1047 processmethod=processmethod, args=args, kw=kw)
1048
1049 add_monthly_task = add_monthday_task
1050
1051
1054 """Add a task to the scheduler based on a cron-like syntax.
1055
1056 @param cron_str: The scheduling information, written in a cron-like syntax
1057
1058 @param action: The callable that will be called at the time you request
1059 @param args: Tuple of positional parameters to pass to the action
1060 @param kw: Keyword arguments to pass to the action
1061 @param taskname: Tasks can have a name (stored in task.name), which can
1062 help if you're trying to keep track of many tasks.
1063 @param processmethod: By default, each task will be run in a new thread.
1064 You can also pass in turbogears.scheduler.method.sequential or
1065 turbogears.scheduler.method.forked.
1066
1067 """
1068 si = _get_scheduler()
1069 return si.add_cron_like_task(action=action, taskname=taskname,
1070 cron_str=cron_str, processmethod=processmethod,
1071 args=args, kw=kw)
1072
1073
1075 """Retrieve a task from the scheduler by task name.
1076
1077 @param taskname: the name of the task to retrieve
1078
1079 """
1080 si = _get_scheduler()
1081 return si.tasks.get(taskname)
1082
1083
1085 """Retrieve all tasks from the scheduler."""
1086 si = _get_scheduler()
1087 return si.tasks
1088
1089
1091 """Rename a scheduled task."""
1092 si = _get_scheduler()
1093 si.rename(taskname, newname)
1094
1095
1097 """Cancel task by task name.
1098
1099 @param task: the task.name of the task to cancel
1100
1101 """
1102 si = _get_scheduler()
1103 si.cancel(task)
1104