class DummyClient(object):
def __init__(self, *args, **kwargs):
self.cache = LRUCache(limit=5000)
def get(self, key, *args, **kwargs):
return self.cache.get(key)
def get_multi(self, keys):
cache = self.cache
return dict((k, cache[k]) for k in keys if k in cache)
def set(self, key, value, *args, **kwargs):
self.cache[key] = value
def delete(self, key, *args, **kwargs):
self.cache.pop(key, None)
def incr(self, key, delta=1):
return self.cache.incr(key, delta)
class DummyClient(object):
def __init__(self, *args, **kwargs):
self.cache = LRUCache(limit=5000)
def get(self, key, *args, **kwargs):
return self.cache.get(key)
def get_multi(self, keys):
cache = self.cache
return dict((k, cache[k]) for k in keys if k in cache)
def set(self, key, value, *args, **kwargs):
self.cache[key] = value
def delete(self, key, *args, **kwargs):
self.cache.pop(key, None)
def incr(self, key, delta=1):
return self.cache.incr(key, delta)
class DummyClient:
def __init__(self, *args, **kwargs):
self.cache = LRUCache(limit=5000)
def get(self, key, *args, **kwargs):
return self.cache.get(key)
def get_multi(self, keys):
cache = self.cache
return {k: cache[k] for k in keys if k in cache}
def set(self, key, value, *args, **kwargs):
self.cache[key] = value
def delete(self, key, *args, **kwargs):
self.cache.pop(key, None)
def incr(self, key, delta=1):
return self.cache.incr(key, delta)
def touch(self, key, expire):
pass
class BaseBackend(object):
READY_STATES = states.READY_STATES
UNREADY_STATES = states.UNREADY_STATES
EXCEPTION_STATES = states.EXCEPTION_STATES
TimeoutError = TimeoutError
#: Time to sleep between polling each individual item
#: in `ResultSet.iterate`. as opposed to the `interval`
#: argument which is for each pass.
subpolling_interval = None
#: If true the backend must implement :meth:`get_many`.
supports_native_join = False
#: If true the backend must automatically expire results.
#: The daily backend_cleanup periodic task will not be triggered
#: in this case.
supports_autoexpire = False
#: Set to true if the backend is peristent by default.
persistent = True
retry_policy = {
'max_retries': 20,
'interval_start': 0,
'interval_step': 1,
'interval_max': 1,
}
def __init__(self, app, serializer=None,
max_cached_results=None, accept=None, **kwargs):
self.app = app
conf = self.app.conf
self.serializer = serializer or conf.CELERY_RESULT_SERIALIZER
(self.content_type,
self.content_encoding,
self.encoder) = serializer_registry._encoders[self.serializer]
self._cache = LRUCache(
limit=max_cached_results or conf.CELERY_MAX_CACHED_RESULTS,
)
self.accept = prepare_accept_content(
conf.CELERY_ACCEPT_CONTENT if accept is None else accept,
)
def mark_as_started(self, task_id, **meta):
"""Mark a task as started"""
return self.store_result(task_id, meta, status=states.STARTED)
def mark_as_done(self, task_id, result, request=None):
"""Mark task as successfully executed."""
return self.store_result(task_id, result,
status=states.SUCCESS, request=request)
def mark_as_failure(self, task_id, exc, traceback=None, request=None):
"""Mark task as executed with failure. Stores the execption."""
return self.store_result(task_id, exc, status=states.FAILURE,
traceback=traceback, request=request)
def fail_from_current_stack(self, task_id, exc=None):
type_, real_exc, tb = sys.exc_info()
try:
exc = real_exc if exc is None else exc
ei = ExceptionInfo((type_, exc, tb))
self.mark_as_failure(task_id, exc, ei.traceback)
return ei
finally:
del(tb)
def mark_as_retry(self, task_id, exc, traceback=None, request=None):
"""Mark task as being retries. Stores the current
exception (if any)."""
return self.store_result(task_id, exc, status=states.RETRY,
traceback=traceback, request=request)
def mark_as_revoked(self, task_id, reason='', request=None):
return self.store_result(task_id, TaskRevokedError(reason),
status=states.REVOKED, traceback=None,
request=request)
def prepare_exception(self, exc):
"""Prepare exception for serialization."""
if self.serializer in EXCEPTION_ABLE_CODECS:
return get_pickleable_exception(exc)
return {'exc_type': type(exc).__name__, 'exc_message': str(exc)}
def exception_to_python(self, exc):
"""Convert serialized exception to Python exception."""
if self.serializer in EXCEPTION_ABLE_CODECS:
return get_pickled_exception(exc)
return create_exception_cls(
from_utf8(exc['exc_type']), __name__)(exc['exc_message'])
def prepare_value(self, result):
"""Prepare value for storage."""
if self.serializer != 'pickle' and isinstance(result, ResultBase):
return result.as_tuple()
return result
def encode(self, data):
_, _, payload = dumps(data, serializer=self.serializer)
return payload
def decode(self, payload):
payload = PY3 and payload or str(payload)
return loads(payload,
content_type=self.content_type,
content_encoding=self.content_encoding,
accept=self.accept)
def wait_for(self, task_id, timeout=None, propagate=True, interval=0.5):
"""Wait for task and return its result.
If the task raises an exception, this exception
will be re-raised by :func:`wait_for`.
If `timeout` is not :const:`None`, this raises the
:class:`celery.exceptions.TimeoutError` exception if the operation
takes longer than `timeout` seconds.
"""
time_elapsed = 0.0
while 1:
status = self.get_status(task_id)
if status == states.SUCCESS:
return self.get_result(task_id)
elif status in states.PROPAGATE_STATES:
result = self.get_result(task_id)
if propagate:
raise result
return result
# avoid hammering the CPU checking status.
time.sleep(interval)
time_elapsed += interval
if timeout and time_elapsed >= timeout:
raise TimeoutError('The operation timed out.')
def prepare_expires(self, value, type=None):
if value is None:
value = self.app.conf.CELERY_TASK_RESULT_EXPIRES
if isinstance(value, timedelta):
value = timeutils.timedelta_seconds(value)
if value is not None and type:
return type(value)
return value
def prepare_persistent(self, enabled=None):
if enabled is not None:
return enabled
p = self.app.conf.CELERY_RESULT_PERSISTENT
return self.persistent if p is None else p
def encode_result(self, result, status):
if status in self.EXCEPTION_STATES and isinstance(result, Exception):
return self.prepare_exception(result)
else:
return self.prepare_value(result)
def is_cached(self, task_id):
return task_id in self._cache
def store_result(self, task_id, result, status,
traceback=None, request=None, **kwargs):
"""Update task state and result."""
result = self.encode_result(result, status)
self._store_result(task_id, result, status, traceback,
request=request, **kwargs)
return result
def forget(self, task_id):
self._cache.pop(task_id, None)
self._forget(task_id)
def _forget(self, task_id):
raise NotImplementedError('backend does not implement forget.')
def get_status(self, task_id):
"""Get the status of a task."""
return self.get_task_meta(task_id)['status']
def get_traceback(self, task_id):
"""Get the traceback for a failed task."""
return self.get_task_meta(task_id).get('traceback')
def get_result(self, task_id):
"""Get the result of a task."""
meta = self.get_task_meta(task_id)
if meta['status'] in self.EXCEPTION_STATES:
return self.exception_to_python(meta['result'])
else:
return meta['result']
def get_children(self, task_id):
"""Get the list of subtasks sent by a task."""
try:
return self.get_task_meta(task_id)['children']
except KeyError:
pass
def get_task_meta(self, task_id, cache=True):
if cache:
try:
return self._cache[task_id]
except KeyError:
pass
meta = self._get_task_meta_for(task_id)
if cache and meta.get('status') == states.SUCCESS:
self._cache[task_id] = meta
return meta
def reload_task_result(self, task_id):
"""Reload task result, even if it has been previously fetched."""
self._cache[task_id] = self.get_task_meta(task_id, cache=False)
def reload_group_result(self, group_id):
"""Reload group result, even if it has been previously fetched."""
self._cache[group_id] = self.get_group_meta(group_id, cache=False)
def get_group_meta(self, group_id, cache=True):
if cache:
try:
return self._cache[group_id]
except KeyError:
pass
meta = self._restore_group(group_id)
if cache and meta is not None:
self._cache[group_id] = meta
return meta
def restore_group(self, group_id, cache=True):
"""Get the result for a group."""
meta = self.get_group_meta(group_id, cache=cache)
if meta:
return meta['result']
def save_group(self, group_id, result):
"""Store the result of an executed group."""
return self._save_group(group_id, result)
def delete_group(self, group_id):
self._cache.pop(group_id, None)
return self._delete_group(group_id)
def cleanup(self):
"""Backend cleanup. Is run by
:class:`celery.task.DeleteExpiredTaskMetaTask`."""
pass
def process_cleanup(self):
"""Cleanup actions to do at the end of a task worker process."""
pass
def on_task_call(self, producer, task_id):
return {}
def on_chord_part_return(self, task, propagate=False):
pass
def fallback_chord_unlock(self, group_id, body, result=None,
countdown=1, **kwargs):
kwargs['result'] = [r.as_tuple() for r in result]
self.app.tasks['celery.chord_unlock'].apply_async(
(group_id, body, ), kwargs, countdown=countdown,
)
def apply_chord(self, header, partial_args, group_id, body, **options):
result = header(*partial_args, task_id=group_id)
self.fallback_chord_unlock(group_id, body, **options)
return result
def current_task_children(self, request=None):
request = request or getattr(current_task(), 'request', None)
if request:
return [r.as_tuple() for r in getattr(request, 'children', [])]
def __reduce__(self, args=(), kwargs={}):
return (unpickle_backend, (self.__class__, args, kwargs))
