def start(self, method=None, method_args=None):
""" Start this job. """
with TransactionLock(self.table, '%s.start' % self):
logger.info("%s: Job starting" % self)
self.refresh()
if self.is_follower:
logger.debug("%s: Shadowing master job %s" %
(self, self.master))
if self.master.status == Job.COMPLETE:
self.mark_complete()
elif self.master.status == Job.ERROR:
self.mark_error(self.master.message,
self.master.exception)
return
if method is None:
method = self.table.queryclass.run
# Create an task to do the work
task = Task(self, Callable(method, method_args))
logger.debug("%s: Created task %s" % (self, task))
task.start()
def check_children(self, objlock=None):
# get a lock on the child that's called us to ensure any status
# from its transaction will be seen.
if objlock is None:
objlock = self
with TransactionLock(objlock, '%s.checking_children' % self):
running_children = Job.objects.filter(
parent=self, status__in=[Job.NEW, Job.RUNNING])
logger.info("%s: %d running children" % (self, len(running_children)))
logger.debug("%s: all children: %s" %
(self, ';'.join('%s - %s' %
(j.status, j) for j in
Job.objects.filter(parent=self))))
if len(running_children) > 0:
# Not done yet, do nothing
return
# Grab a lock on this job to make sure only one caller
# gets the callback
with TransactionLock(self, '%s.check_children' % self):
# Now that we have the lock, make sure we have latest Job
# details
self.refresh()
logger.info("%s: checking callback %s" % (self, self.callback))
if self.callback is None:
# Some other child got to it first
return
# Save off the callback, we'll call it outside the transaction
callback = self.callback
# Clear the callback while still in lockdown
self.callback = None
self.save()
t = Task(self, callback=callback)
logger.info("%s: Created callback task %s" % (self, t))
t.start()
def check_children(self, objlock=None):
# get a lock on the child that's called us to ensure any status
# from its transaction will be seen.
if objlock is None:
objlock = self
with TransactionLock(objlock, '%s.checking_children' % self):
running_children = Job.objects.filter(
parent=self, status__in=[Job.NEW, Job.RUNNING])
logger.info("%s: %d running children" % (self, len(running_children)))
logger.debug(
"%s: all children: %s" %
(self, ';'.join('%s - %s' % (j.status, j)
for j in Job.objects.filter(parent=self))))
if len(running_children) > 0:
# Not done yet, do nothing
return
# Grab a lock on this job to make sure only one caller
# gets the callback
with TransactionLock(self, '%s.check_children' % self):
# Now that we have the lock, make sure we have latest Job
# details
self.refresh()
logger.info("%s: checking callback %s" % (self, self.callback))
if self.callback is None:
# Some other child got to it first
return
# Save off the callback, we'll call it outside the transaction
callback = self.callback
# Clear the callback while still in lockdown
self.callback = None
self.save()
t = Task(self, callback=callback)
logger.info("%s: Created callback task %s" % (self, t))
t.start()
def mark_done(self, status, **kwargs):
with TransactionLock(self, '%s.mark_done' % self):
self.refresh()
old_status = self.status
if old_status in (Job.COMPLETE, Job.ERROR):
# Status was already set to a done state, avoid
# double action and return now
return
self.status = status
for k, v in kwargs.iteritems():
setattr(self, k, v)
self.save()
# On status change, do more...
self.mark_progress(status=status,
progress=100)
if not self.is_follower:
# Notify followers of this job
followers = Job.objects.filter(master=self)
for follower in followers:
if self.status == Job.COMPLETE:
kwargs['actual_criteria'] = self.actual_criteria
follower.mark_complete(status=status, **kwargs)
elif self.status == Job.ERROR:
follower.mark_done(status=status, **kwargs)
if self.parent:
logger.info("%s: Asking parent %s to check children" %
(self, self.parent))
t = Task(self.parent,
callback=Callable(self.parent.check_children,
called_kwargs={'objlock': self}),
generic=True)
logger.info("%s: Created check_children task %s" % (self, t))
t.start()
return True
def mark_done(self, status, **kwargs):
with TransactionLock(self, '%s.mark_done' % self):
self.refresh()
old_status = self.status
if old_status in (Job.COMPLETE, Job.ERROR):
# Status was already set to a done state, avoid
# double action and return now
return
self.status = status
for k, v in kwargs.iteritems():
setattr(self, k, v)
self.save()
# On status change, do more...
self.mark_progress(status=status, progress=100)
if not self.is_follower:
# Notify followers of this job
followers = Job.objects.filter(master=self)
for follower in followers:
if self.status == Job.COMPLETE:
kwargs['actual_criteria'] = self.actual_criteria
follower.mark_complete(status=status, **kwargs)
elif self.status == Job.ERROR:
follower.mark_done(status=status, **kwargs)
if self.parent:
logger.info("%s: Asking parent %s to check children" %
(self, self.parent))
t = Task(self.parent,
callback=Callable(self.parent.check_children,
called_kwargs={'objlock': self}),
generic=True)
logger.info("%s: Created check_children task %s" % (self, t))
t.start()
return True
def start(self, method=None, method_args=None):
""" Start this job. """
with TransactionLock(self.table, '%s.start' % self):
logger.info("%s: Job starting" % self)
self.refresh()
if self.is_follower:
logger.debug("%s: Shadowing master job %s" %
(self, self.master))
if self.master.status == Job.COMPLETE:
self.mark_complete()
elif self.master.status == Job.ERROR:
self.mark_error(self.master.message, self.master.exception)
return
if method is None:
method = self.table.queryclass.run
# Create an task to do the work
task = Task(self, Callable(method, method_args))
logger.debug("%s: Created task %s" % (self, task))
task.start()
def get_master(self, handle):
"""Return Job object for master or None if no valid jobs found."""
master = None
# Find jobs with the same handle but with no master,
# these are candidate master jobs. Lock these rows
# so we can ensure they don't get deleted until
# we have a chance to touch it and refcount the selected
# master below
candidates = (Job.objects.select_for_update().filter(
status__in=[Job.NEW, Job.QUEUED, Job.RUNNING, Job.COMPLETE],
handle=handle,
master=None).order_by('created'))
if candidates:
master_jobs = Task.validate_jobs(jobs=candidates, delete=True)
master = master_jobs[0] if master_jobs else None
return master
def get_master(self, handle):
"""Return Job object for master or None if no valid jobs found."""
master = None
# Find jobs with the same handle but with no master,
# these are candidate master jobs. Lock these rows
# so we can ensure they don't get deleted until
# we have a chance to touch it and refcount the selected
# master below
candidates = (Job.objects
.select_for_update()
.filter(status__in=[Job.NEW,
Job.QUEUED,
Job.RUNNING,
Job.COMPLETE],
handle=handle,
master=None)
.order_by('created'))
if candidates:
master_jobs = Task.validate_jobs(jobs=candidates, delete=True)
master = master_jobs[0] if master_jobs else None
return master
