Files
django-q2/django_q/tasks.py
T

418 lines
13 KiB
Python

"""Provides task functionality."""
from multiprocessing import Queue, Value
# django
from django.utils import timezone
# local
import time
import signing
import cluster
from django_q.conf import Conf, logger
from django_q.models import Schedule, Task
from django_q.humanhash import uuid
from django_q.brokers import get_broker
def async(func, *args, **kwargs):
"""Queue a task for the cluster."""
# get options from q_options dict or direct from kwargs
options = kwargs.pop('q_options', kwargs)
hook = options.pop('hook', None)
broker = options.pop('broker', get_broker())
sync = options.pop('sync', False)
group = options.pop('group', None)
save = options.pop('save', None)
cached = options.pop('cached', Conf.CACHED)
iter_count = options.pop('iter_count', None)
iter_cached = options.pop('iter_cached', None)
# get an id
tag = uuid()
# build the task package
task = {'id': tag[1], 'name': tag[0],
'func': func,
'args': args,
'kwargs': kwargs,
'started': timezone.now()}
# add optionals
if hook:
task['hook'] = hook
if group:
task['group'] = group
if save is not None:
task['save'] = save
if cached:
task['cached'] = cached
if iter_count:
task['iter_count'] = iter_count
if iter_cached:
task['iter_cached'] = iter_cached
# sign it
pack = signing.SignedPackage.dumps(task)
if sync or Conf.SYNC:
return _sync(pack)
# push it
broker.enqueue(pack)
logger.debug('Pushed {}'.format(tag))
return task['id']
def schedule(func, *args, **kwargs):
"""
Create a schedule.
:param func: function to schedule.
:param args: function arguments.
:param name: optional name for the schedule.
:param hook: optional result hook function.
:type schedule_type: Schedule.TYPE
:param repeats: how many times to repeat. 0=never, -1=always.
:param next_run: Next scheduled run.
:type next_run: datetime.datetime
:param kwargs: function keyword arguments.
:return: the schedule object.
:rtype: Schedule
"""
name = kwargs.pop('name', None)
hook = kwargs.pop('hook', None)
schedule_type = kwargs.pop('schedule_type', Schedule.ONCE)
minutes = kwargs.pop('minutes', None)
repeats = kwargs.pop('repeats', -1)
next_run = kwargs.pop('next_run', timezone.now())
return Schedule.objects.create(name=name,
func=func,
hook=hook,
args=args,
kwargs=kwargs,
schedule_type=schedule_type,
minutes=minutes,
repeats=repeats,
next_run=next_run
)
def result(task_id, wait=0, cached=Conf.CACHED):
"""
Return the result of the named task.
:type task_id: str or uuid
:param task_id: the task name or uuid
:type wait: int
:param wait: number of milliseconds to wait for a result
:param bool cached: run this against the cache backend
:return: the result object of this task
:rtype: object
"""
if cached:
return result_cached(task_id, wait)
start = time.time()
while True:
r = Task.get_result(task_id)
if r:
return r
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def result_cached(task_id, wait=0, broker=None):
"""
Return the result from the cache backend
"""
if not broker:
broker = get_broker()
start = time.time()
while True:
r = broker.cache.get('{}:{}'.format(broker.list_key, task_id))
if r:
return signing.SignedPackage.loads(r)['result']
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def result_group(group_id, failures=False, wait=0, count=None, cached=Conf.CACHED):
"""
Return a list of results for a task group.
:param str group_id: the group id
:param bool failures: set to True to include failures
:param int count: Block until there are this many results in the group
:param bool cached: run this against the cache backend
:return: list or results
"""
if cached:
return result_group_cached(group_id, failures, wait, count)
start = time.time()
if count:
while True:
if count_group(group_id) == count or wait and (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
while True:
r = Task.get_result_group(group_id, failures)
if r:
return r
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def result_group_cached(group_id, failures=False, wait=0, count=None, broker=None):
"""
Return a list of results for a task group from the cache backend
"""
if not broker:
broker = get_broker()
start = time.time()
if count:
while True:
if count_group_cached(group_id) == count or wait and (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
while True:
group_list = broker.cache.get('{}:{}:keys'.format(broker.list_key, group_id))
if group_list:
result_list = []
for task_key in group_list:
task = signing.SignedPackage.loads(broker.cache.get(task_key))
if task['success'] or failures:
result_list.append(task['result'])
return result_list
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def fetch(task_id, wait=0, cached=Conf.CACHED):
"""
Return the processed task.
:param task_id: the task name or uuid
:type task_id: str or uuid
:param wait: the number of milliseconds to wait for a result
:type wait: int
:param bool cached: run this against the cache backend
:return: the full task object
:rtype: Task
"""
if cached:
return fetch_cached(task_id, wait)
start = time.time()
while True:
t = Task.get_task(task_id)
if t:
return t
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def fetch_cached(task_id, wait=0, broker=None):
"""
Return the processed task from the cache backend
"""
if not broker:
broker = get_broker()
start = time.time()
while True:
r = broker.cache.get('{}:{}'.format(broker.list_key, task_id))
if r:
task = signing.SignedPackage.loads(r)
t = Task(id=task['id'],
name=task['name'],
func=task['func'],
hook=task.get('hook'),
args=task['args'],
kwargs=task['kwargs'],
started=task['started'],
stopped=task['stopped'],
result=task['result'],
success=task['success'])
return t
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def fetch_group(group_id, failures=True, wait=0, count=None, cached=Conf.CACHED):
"""
Return a list of Tasks for a task group.
:param str group_id: the group id
:param bool failures: set to False to exclude failures
:param bool cached: run this against the cache backend
:return: list of Tasks
"""
if cached:
return fetch_group_cached(group_id, failures, wait, count)
start = time.time()
if count:
while True:
if count_group(group_id) == count or wait and (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
while True:
r = Task.get_task_group(group_id, failures)
if r:
return r
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def fetch_group_cached(group_id, failures=True, wait=0, count=None, broker=None):
"""
Return a list of Tasks for a task group in the cache backend
"""
if not broker:
broker = get_broker()
start = time.time()
if count:
while True:
if count_group_cached(group_id) == count or wait and (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
while True:
group_list = broker.cache.get('{}:{}:keys'.format(broker.list_key, group_id))
if group_list:
task_list = []
for task_key in group_list:
task = signing.SignedPackage.loads(broker.cache.get(task_key))
if task['success'] or failures:
t = Task(id=task['id'],
name=task['name'],
func=task['func'],
hook=task.get('hook'),
args=task['args'],
kwargs=task['kwargs'],
started=task['started'],
stopped=task['stopped'],
result=task['result'],
group=task.get('group'),
success=task['success'])
task_list.append(t)
return task_list
if (time.time() - start) * 1000 >= wait:
break
time.sleep(0.01)
def count_group(group_id, failures=False, cached=Conf.CACHED):
"""
Count the results in a group.
:param str group_id: the group id
:param bool failures: Returns failure count if True
:param bool cached: run this against the cache backend
:return: the number of tasks/results in a group
:rtype: int
"""
if cached:
return count_group_cached(group_id, failures)
return Task.get_group_count(group_id, failures)
def count_group_cached(group_id, failures=False, broker=None):
"""
Count the results in a group in the cache backend
"""
if not broker:
broker = get_broker()
group_list = broker.cache.get('{}:{}:keys'.format(broker.list_key, group_id))
if group_list:
if not failures:
return len(group_list)
failure_count = 0
for task_key in group_list:
task = signing.SignedPackage.loads(broker.cache.get(task_key))
if not task['success']:
failure_count += 1
return failure_count
def delete_group(group_id, tasks=False, cached=Conf.CACHED):
"""
Delete a group.
:param str group_id: the group id
:param bool tasks: If set to True this will also delete the group tasks.
Otherwise just the group label is removed.
:param bool cached: run this against the cache backend
:return:
"""
if cached:
return delete_group_cached(group_id)
return Task.delete_group(group_id, tasks)
def delete_group_cached(group_id, broker=None):
"""
Delete a group from the cache backend
"""
if not broker:
broker = get_broker()
group_key = '{}:{}:keys'.format(broker.list_key, group_id)
group_list = broker.cache.get(group_key)
broker.cache.delete_many(group_list)
broker.cache.delete(group_key)
def delete_cached(task_id, broker=None):
"""
Delete a task from the cache backend
"""
if not broker:
broker = get_broker()
return broker.cache.delete('{}:{}'.format(broker.list_key, task_id))
def queue_size(broker=None):
"""
Returns the current queue size.
Note that this doesn't count any tasks curren key = 'django_q:{}:results'.format(broker.list_key)tly being processed by workers.
:param broker: optional broker
:return: current queue size
:rtype: int
"""
if not broker:
broker = get_broker()
return broker.queue_size()
def async_iter(func, args_iter, **kwargs):
iter_count = len(args_iter)
iter_group = uuid()[1]
# clean up the kwargs
options = kwargs.get('q_options', kwargs)
options.pop('hook', None)
options['broker'] = options.get('broker', get_broker())
options['group'] = iter_group
options['iter_count'] = iter_count
if options.get('cached', None):
options['iter_cached'] = options['cached']
options['cached'] = True
# save the original arguments
broker = options['broker']
broker.cache.set('{}:{}:args'.format(broker.list_key, iter_group), signing.SignedPackage.dumps(args_iter))
for args in args_iter:
if type(args) is not tuple:
args = (args,)
async(func, *args, **options)
return iter_group
def _sync(pack):
"""Simulate a package travelling through the cluster."""
task_queue = Queue()
result_queue = Queue()
task = signing.SignedPackage.loads(pack)
task_queue.put(task)
task_queue.put('STOP')
cluster.worker(task_queue, result_queue, Value('f', -1))
result_queue.put('STOP')
cluster.monitor(result_queue)
return task['id']