Package turbogears :: Module scheduler

Module scheduler

Module that provides a cron-like task scheduler.

This task scheduler is designed to be used from inside your own program.
You can schedule Python functions to be called at specific intervals or
days. It uses the standard 'sched' module for the actual task scheduling,
but provides much more:

* repeated tasks (at intervals, or on specific days)
* error handling (exceptions in tasks don't kill the scheduler)
* optional to run scheduler in its own thread or separate process
* optional to run a task in its own thread or separate process

If the threading module is available, you can use the various Threaded
variants of the scheduler and associated tasks. If threading is not
available, you could still use the forked variants. If fork is also
not available, all processing is done in a single process, sequentially.

There are three Scheduler classes:

    Scheduler    ThreadedScheduler    ForkedScheduler

You usually add new tasks to a scheduler using the add_interval_task or
add_daytime_task methods, with the appropriate processmethod argument
to select sequential, threaded or forked processing. NOTE: it is impossible
to add new tasks to a ForkedScheduler, after the scheduler has been started!
For more control you can use one of the following Task classes
and use schedule_task or schedule_task_abs:

    IntervalTask    ThreadedIntervalTask    ForkedIntervalTask
    SingleTask      ThreadedSingleTask      ForkedSingleTask
    WeekdayTask     ThreadedWeekdayTask     ForkedWeekdayTask
    CronLikeTask    ThreadedCronLikeTask    ForkedCronLikeTask

Kronos is the Greek god of time. Kronos scheduler (c) by Irmen de Jong.

This module is based on the Kronos scheduler by Irmen de Jong, but has been
modified to better fit within TurboGears. Vince Spicer and Mathieu Bridon have
contributed some additions and improvements such as cron-like tasks. Some fixes
have been made to make it work on Python 2.6 (adaptations sched module changes).

Version: 2.0

Classes
	Scheduler The Scheduler itself.
	Task Abstract base class of all scheduler tasks
	SingleTask A task that only runs once.
	IntervalTask A repeated task that occurs at certain intervals (in seconds).
	WeekdayTask A task that is run on a given weekday.
	MonthdayTask A task that is run on a given day every month.
	ThreadedScheduler A Scheduler that runs in its own thread.
	ThreadedTaskMixin A mixin class to make a Task execute in a separate thread.
	ThreadedIntervalTask Interval Task that executes in its own thread.
	ThreadedSingleTask Single Task that executes in its own thread.
	ThreadedWeekdayTask Weekday Task that executes in its own thread.
	ThreadedMonthdayTask Monthday Task that executes in its own thread.
	ForkedScheduler A Scheduler that runs in its own forked process.
	ForkedTaskMixin A mixin class to make a Task execute in a separate process.
	ForkedIntervalTask Interval Task that executes in its own process.
	ForkedSingleTask Single Task that executes in its own process.
	ForkedWeekdayTask Weekday Task that executes in its own process.
	ForkedMonthdayTask Monthday Task that executes in its own process.

Functions

add_interval_task(action, interval, args=None, kw=None, initialdelay=0, processmethod=method.threaded, taskname=None)
Add an interval task to the scheduler.

source code

add_single_task(action, args=None, kw=None, initialdelay=0, processmethod=method.threaded, taskname=None)
Add a single task to the scheduler.

source code

add_weekday_task(action, weekdays, timeonday, args=None, kw=None, processmethod=method.threaded, taskname=None)
Add a weekday task to the scheduler.

source code

add_monthday_task(action, monthdays, timeonday, args=None, kw=None, processmethod=method.threaded, taskname=None)
Add a monthly task to the scheduler.

source code

cancel(task)
Cancel task by task name.

source code

Variables
	method = `Enum('sequential', 'forked', 'threaded')`

Function Details

add_interval_task(action, interval, args=None, kw=None, initialdelay=0, processmethod=method.threaded, taskname=None)

source code

Add an interval task to the scheduler.

Pass in initialdelay with a number of seconds to wait before running and an interval with the number of seconds between runs.

For example, an initialdelay of 600 and interval of 60 would mean "start running after 10 minutes and run every 1 minute after that".

Parameters:

interval - The interval in seconds between executing the action
initaldelay - the initial delay before starting execution
action - The callable that will be called at the time you request
args - Tuple of positional parameters to pass to the action
kw - Keyword arguments to pass to the action
taskname - Tasks can have a name (stored in task.name), which can help if you're trying to keep track of many tasks.
precessmethod - By default, each task will be run in a new thread. You can also pass in turbogears.scheduler.method.sequential or turbogears.scheduler.method.forked.

add_single_task(action, args=None, kw=None, initialdelay=0, processmethod=method.threaded, taskname=None)

source code

Add a single task to the scheduler.

Runs a task once. Pass in ``initialdelay`` with a number of seconds to wait before running.

Parameters:

initaldelay - the initial delay before starting execution
action - The callable that will be called at the time you request
args - Tuple of positional parameters to pass to the action
kw - Keyword arguments to pass to the action
taskname - Tasks can have a name (stored in task.name), which can help if you're trying to keep track of many tasks.
precessmethod - By default, each task will be run in a new thread. You can also pass in turbogears.scheduler.method.sequential or turbogears.scheduler.method.forked.

add_weekday_task(action, weekdays, timeonday, args=None, kw=None, processmethod=method.threaded, taskname=None)

source code

Add a weekday task to the scheduler.

Runs on certain days of the week. Pass in a list or tuple of weekdays from 1-7 (where 1 is Monday). Additionally, you need to pass in timeonday which is the time of day to run. timeonday should be a tuple with (hour, minute).

Parameters:

weekdays - list ot tuple of weekdays to execute action
timeonday - tuple (hour, minute), to run on weekday
action - The callable that will be called at the time you request
args - Tuple of positional parameters to pass to the action
kw - Keyword arguments to pass to the action
taskname - Tasks can have a name (stored in task.name), which can help if you're trying to keep track of many tasks.
precessmethod - By default, each task will be run in a new thread. You can also pass in turbogears.scheduler.method.sequential or turbogears.scheduler.method.forked.

add_monthday_task(action, monthdays, timeonday, args=None, kw=None, processmethod=method.threaded, taskname=None)

source code

Add a monthly task to the scheduler.

Runs on certain days of the month. Pass in a list or tuple of monthdays
from 1-31, import and also pass in timeonday which is an (hour, minute)
 tuple of the time of day to run the task.

@param monthdays: list ot tuple of monthdays to execute action
@param timeonday: tuple (hour, minute), to run on monthday

@param action: The callable that will be called at the time you request
@param args: Tuple of positional parameters to pass to the action
@param kw: Keyword arguments to pass to the action
@param taskname:  Tasks can have a name (stored in task.name), which can
help if you're trying to keep track of many tasks.
@param precessmethod: By default, each task will be run in a new thread.
You can also pass in turbogears.scheduler.method.sequential or
turbogears.scheduler.method.forked.

cancel(task)

source code

Cancel task by task name.

Parameters:

task - the task.name of the task to cancel