Class Retry

celery/exceptions.py:145–184

The task is to be retried later.

class Retry(TaskPredicate):
    """The task is to be retried later."""

    #: Optional message describing context of retry.
    message = None

    #: Exception (if any) that caused the retry to happen.
    exc = None

    #: Time of retry (ETA), either :class:`numbers.Real` or
    #: :class:`~datetime.datetime`.
    when = None

    def __init__(self, message=None, exc=None, when=None, is_eager=False,
                 sig=None, **kwargs):
        from kombu.utils.encoding import safe_repr
        self.message = message
        if isinstance(exc, str):
            self.exc, self.excs = None, exc
        else:
            self.exc, self.excs = get_pickleable_exception(exc), safe_repr(exc) if exc else None
        self.when = when
        self.is_eager = is_eager
        self.sig = sig
        super().__init__(self, exc, when, **kwargs)

    def humanize(self):
        if isinstance(self.when, numbers.Number):
            return f'in {self.when}s'
        return f'at {self.when}'

    def __str__(self):
        if self.message:
            return self.message
        if self.excs:
            return f'Retry {self.humanize()}: {self.excs}'
        return f'Retry {self.humanize()}'

    def __reduce__(self):
        return self.__class__, (self.message, self.exc, self.when)


RetryTaskError = Retry  # XXX compat