TaskKit.Scheduler | index /usr/local/share/webware/TaskKit/Scheduler.py

`This is the TaskManager Python package.
It provides a system for running any number of predefined tasks in separate
threads in an organized and controlled manner.
A task in this package is a class derived from the Task class. The task
should have a run method that, when called, performs some task.
The Scheduler class is the organizing object. It manages the addition,
execution, deletion, and well being of a number of tasks. Once you have
created your task class, you call the Scheduler to get it added to the
tasks to be run.`

Classes

``

threading.Thread(threading._Verbose)
  Scheduler

class Scheduler(threading.Thread)
`` | `The top level class of the TaskManager system. The Scheduler is a thread that handles organizing and running tasks. The Scheduler class should be instantiated to start a TaskManager sessions. Its start method should be called to start the TaskManager. Its stop method should be called to end the TaskManager session.`

Method resolution order:
  Scheduler
  threading.Thread
  threading._Verbose
  __builtin__.object

Methods defined here:

__init__(self, daemon=True, exceptionHandler=None)

addActionOnDemand(self, task, name)
  `Add a task to be run only on demand.
  Adds a task to the scheduler that will not be scheduled
  until specifically requested.`

addDailyAction(self, hour, minute, task, name)
  `Add an action to be run every day at a specific time.
  If a task with the given name is already registered with the
  scheduler, that task will be removed from the scheduling queue
  and registered anew as a periodic task.
  Can we make this addCalendarAction? What if we want to run
  something once a week? We probably don't need that for Webware,
  but this is a more generally useful module. This could be a
  difficult function, though. Particularly without mxDateTime.`

addPeriodicAction(self, start, period, task, name)
  `Add a task to be run periodically.
  Adds an action to be run at a specific initial time,
  and every period thereafter.
  The scheduler will not reschedule a task until the last
  scheduled instance of the task has completed.
  If a task with the given name is already registered with
  the scheduler, that task will be removed from the scheduling
  queue and registered anew as a periodic task.`

addTimedAction(self, time, task, name)
  `Add a task to be run once, at a specific time.`

delOnDemand(self, name)
  `Delete a task with the given name from the onDemand list.`

delRunning(self, name)
  `Delete a task from the running list.
  Used Internally.`

delScheduled(self, name)
  `Delete a task with the given name from the scheduled list.`

demandTask(self, name)
  `Demand execution of a task.
  Allow the server to request that a task listed as being registered
  on-demand be run as soon as possible.
  If the task is currently running, it will be flagged to run again
  as soon as the current run completes.
  Returns False if the task name could not be found on the on-demand
  or currently running lists.`

disableTask(self, name)
  `Specify that a task be suspended.
  Suspended tasks will not be scheduled until later enabled.
  If the task is currently running, it will not be interfered
  with, but the task will not be scheduled for execution in
  future until re-enabled.
  Returns True if the task was found and disabled.`

enableTask(self, name)
  `Enable a task again.
  This method is provided to specify that a task be re-enabled
  after a suspension. A re-enabled task will be scheduled for
  execution according to its original schedule, with any runtimes
  that would have been issued during the time the task was suspended
  simply skipped.
  Returns True if the task was found and enabled.`

hasOnDemand(self, name)
  `Checks whether task with given name is in the onDemand list?`

hasRunning(self, name)
  `Check to see if a task with the given name is currently running.`

hasScheduled(self, name)
  `Checks whether task with given name is in the scheduled list.`

isRunning(self)

nextTime(self)

notify(self)

notifyCompletion(self, handle)
  `Notify completion of a task.
  Used by instances of TaskHandler to let the Scheduler thread know
  when their tasks have run to completion. This method is responsible
  for rescheduling the task if it is a periodic task.`

notifyFailure(self, handle)
  `Notify failure of a task.
  Used by instances of TaskHandler to let the Scheduler thread know
  if an exception has occurred within the task thread.`

onDemand(self, name, default=None)
  `Return a task from the onDemand list.`

onDemandTasks(self)

run(self)
  `Run task in a background thread.
  This method is responsible for carrying out the scheduling work of
  this class on a background thread. The basic logic is to wait until
  the next action is due to run, move the task from our scheduled
  list to our running list, and run it. Other synchronized methods
  such as runTask(), scheduleTask(), and notifyCompletion(), may
  be called while this method is waiting for something to happen.
  These methods modify the data structures that run() uses to
  determine its scheduling needs.`

runTask(self, handle)
  `Run a task.
  Used by the Scheduler thread's main loop to put a task in
  the scheduled hash onto the run hash.`

runTaskNow(self, name)
  `Allow a registered task to be immediately executed.
  Returns True if the task is either currently running or was started,
  or False if the task could not be found in the list of currently
  registered tasks.`

running(self, name, default=None)
  `Return running task with given name.
  Returns a task with the given name from the "running" list,
  if it is present there.`

runningTasks(self)

scheduleTask(self, handle)
  `Schedule a task.
  This method takes a task that needs to be scheduled and adds it
  to the scheduler. All scheduling additions or changes are handled
  by this method. This is the only Scheduler method that can notify
  the run() method that it may need to wake up early to handle a
  newly registered task.`

scheduled(self, name, default=None)
  `Return a task from the scheduled list.`

scheduledTasks(self)

setNextTime(self, time)

setOnDemand(self, handle)
  `Add the given task to the onDemand list.`

setRunning(self, handle)
  `Add a task to the running dictionary.
  Used internally only.`

setScheduled(self, handle)
  `Add the given task to the scheduled list.`

start(self)
  `Start the scheduler's activity.`

stop(self)
  `Terminate the scheduler and its associated tasks.`

stopAllTasks(self)
  `Terminate all running tasks.`

stopTask(self, name)
  `Put an immediate halt to a running background task.
  Returns True if the task was either not running, or was
  running and was told to stop.`

unregisterTask(self, name)
  `Unregisters the named task.
  After that it can be rescheduled with different parameters,
  or simply removed.`

wait(self, seconds=None)
  `Our own version of wait().
  When called, it waits for the specified number of seconds, or until
  it is notified that it needs to wake up, through the notify event.`

Methods inherited from threading.Thread:

__repr__(self)

getName(self)

isAlive(self)

isDaemon(self)

join(self, timeout=None)

setDaemon(self, daemonic)

setName(self, name)

Data descriptors inherited from threading._Verbose:

__dict__
  `dictionary for instance variables (if defined)`

__weakref__
  `list of weak references to the object (if defined)`

Functions

``

time(...)
  `time() -> floating point number
  Return the current time in seconds since the Epoch.
  Fractions of a second may be present if the system clock provides them.`