def do_task(self, **params):
"""Perform the next ready task in the queue.
"""
# Get next task and lock it.
t = model.Task.next()
if not t:
self.log.info("No ready tasks found.")
return LOOP_SLEEP
t.start(self)
Session.commit()
if not t.check_lock(self):
# Another worker got the task, abort.
return LOOP_CONTINUE
# Perform task
self.log.info("Starting task: {0}".format(t))
fn = get_task_method(t.method)
try:
r = fn(task_id=t.id, **t.params)
self.log.info("Task completed: {0}".format(t))
t.complete(self)
except TaskDelayResource, e:
new = t.retry(self, delay=e.delay)
self.log.warn("Task error, will retry in {0} seconds: {1}".format(e.delay, e.message))
resource = e.resource or t.resource_group
if resource:
self.log.warn("Delaying resource group by {0} seconds: {1}".format(e.delay, resource))
model.Task.delay_resource_group(resource, timedelta(seconds=e.delay))
def rebuild(worker, **params):
method = params.get('method')
if not method:
log.error("No rebuild method given.")
fn = get_task_method(method)
if not fn:
log.error("Rebuild method not found: %s" % method)
log.debug("Deleting pending tasks.")
t = model.Task.__table__
q = t.delete().where(t.c.state<'completed')
Session.execute(q).close()
Session.commit()
fn(worker)