This document describes the current stable version of Celery (4.3). For development docs, go here.

Built-in task states.

Sets

READY_STATES

Set of states meaning the task result is ready (has been executed).

UNREADY_STATES

Set of states meaning the task result is not ready (hasn’t been executed).

EXCEPTION_STATES

Set of states meaning the task returned an exception.

PROPAGATE_STATES

Set of exception states that should propagate exceptions to the user.

ALL_STATES

Set of all possible states.

Misc

celery.states.PENDING = 'PENDING'

Task state is unknown (assumed pending since you know the id).

celery.states.RECEIVED = 'RECEIVED'

Task was received by a worker (only used in events).

celery.states.STARTED = 'STARTED'

Task was started by a worker (task_track_started).

celery.states.SUCCESS = 'SUCCESS'

Task succeeded

celery.states.FAILURE = 'FAILURE'

Task failed

celery.states.REVOKED = 'REVOKED'

Task was revoked.

celery.states.RETRY = 'RETRY'

Task is waiting for retry.

celery.states.precedence(state)[source]

Get the precedence index for state.

Lower index means higher precedence.

class celery.states.state[source]

Task state.

State is a subclass of str, implementing comparison methods adhering to state precedence rules:

>>> from celery.states import state, PENDING, SUCCESS

>>> state(PENDING) < state(SUCCESS)
True

Any custom state is considered to be lower than FAILURE and SUCCESS, but higher than any of the other built-in states:

>>> state('PROGRESS') > state(STARTED)
True

>>> state('PROGRESS') > state('SUCCESS')
False