# Change history {#changelog-5.1}

This document contains change notes for bugfix & new features in the &
5.1.x series, please see `whatsnew-5.1`{.interpreted-text role="ref"}
for an overview of what\'s new in Celery 5.1.

## 5.1.2

release-date

:   2021-06-28 16.15 P.M UTC+3:00

release-by

:   Omer Katz

-   When chords fail, correctly call errbacks. (#6814)

    > We had a special case for calling errbacks when a chord failed
    > which assumed they were old style. This change ensures that we
    > call the proper errback dispatch method which understands new and
    > old style errbacks, and adds test to confirm that things behave as
    > one might expect now.

-   Avoid using the `Event.isSet()` deprecated alias. (#6824)

-   Reintroduce sys.argv default behaviour for `Celery.start()`. (#6825)

## 5.1.1

release-date

:   2021-06-17 16.10 P.M UTC+3:00

release-by

:   Omer Katz

-   Fix `--pool=threads` support in command line options parsing.
    (#6787)

-   Fix `LoggingProxy.write()` return type. (#6791)

-   Couchdb key is now always coerced into a string. (#6781)

-   

    grp is no longer imported unconditionally. (#6804)

    :   This fixes a regression in 5.1.0 when running Celery in non-unix
        systems.

-   Ensure regen utility class gets marked as done when concertised.
    (#6789)

-   Preserve call/errbacks of replaced tasks. (#6770)

-   Use single-lookahead for regen consumption. (#6799)

-   Revoked tasks are no longer incorrectly marked as retried. (#6812,
    #6816)

## 5.1.0

release-date

:   2021-05-23 19.20 P.M UTC+3:00

release-by

:   Omer Katz

-   `celery -A app events -c camera` now works as expected. (#6774)
-   Bump minimum required Kombu version to 5.1.0.

## 5.1.0rc1 {#version-5.1.0rc1}

release-date

:   2021-05-02 16.06 P.M UTC+3:00

release-by

:   Omer Katz

-   Celery Mailbox accept and serializer parameters are initialized from
    configuration. (#6757)
-   Error propagation and errback calling for group-like signatures now
    works as expected. (#6746)
-   Fix sanitization of passwords in sentinel URIs. (#6765)
-   Add LOG_RECEIVED to customize logging. (#6758)

## 5.1.0b2 {#version-5.1.0b2}

release-date

:   2021-05-02 16.06 P.M UTC+3:00

release-by

:   Omer Katz

-   Fix the behavior of our json serialization which regressed in 5.0.
    (#6561)
-   Add support for SQLAlchemy 1.4. (#6709)
-   Safeguard against schedule entry without kwargs. (#6619)
-   `task.apply_async(ignore_result=True)` now avoids persisting the
    results. (#6713)
-   Update systemd tmpfiles path. (#6688)
-   Ensure AMQPContext exposes an app attribute. (#6741)
-   Inspect commands accept arguments again (#6710).
-   Chord counting of group children is now accurate. (#6733)
-   Add a setting
    `worker_cancel_long_running_tasks_on_connection_loss`{.interpreted-text
    role="setting"} to terminate tasks with late acknowledgement on
    connection loss. (#6654)
-   The `task-revoked` event and the `task_revoked` signal are not
    duplicated when `Request.on_failure` is called. (#6654)
-   Restore pickling support for `Retry`. (#6748)
-   Add support in the redis result backend for authenticating with a
    username. (#6750)
-   The `worker_pool`{.interpreted-text role="setting"} setting is now
    respected correctly. (#6711)

## 5.1.0b1 {#version-5.1.0b1}

release-date

:   2021-04-02 10.25 P.M UTC+6:00

release-by

:   Asif Saif Uddin

-   Add sentinel_kwargs to Redis Sentinel docs.
-   Depend on the maintained python-consul2 library. (#6544).
-   Use result_chord_join_timeout instead of hardcoded default value.
-   Upgrade AzureBlockBlob storage backend to use Azure blob storage
    library v12 (#6580).
-   Improved integration tests.
-   pass_context for handle_preload_options decorator (#6583).
-   Makes regen less greedy (#6589).
-   Pytest worker shutdown timeout (#6588).
-   Exit celery with non zero exit value if failing (#6602).
-   Raise BackendStoreError when set value is too large for Redis.
-   Trace task optimizations are now set via Celery app instance.
-   Make trace_task_ret and fast_trace_task public.
-   reset_worker_optimizations and create_request_cls has now app as
    optional parameter.
-   Small refactor in exception handling of on_failure (#6633).
-   Fix for issue #5030 \"Celery Result backend on Windows OS\".
-   Add store_eager_result setting so eager tasks can store result on
    the result backend (#6614).
-   Allow heartbeats to be sent in tests (#6632).
-   Fixed default visibility timeout note in sqs documentation.
-   Support Redis Sentinel with SSL.
-   Simulate more exhaustive delivery info in apply().
-   Start chord header tasks as soon as possible (#6576).
-   Forward shadow option for retried tasks (#6655).
-   \--quiet flag now actually makes celery avoid producing logs
    (#6599).
-   Update platforms.py \"superuser privileges\" check (#6600).
-   Remove unused property [autoregister]{.title-ref} from the Task
    class (#6624).
-   fnmatch.translate() already translates globs for us. (#6668).
-   Upgrade some syntax to Python 3.6+.
-   Add [azureblockblob_base_path]{.title-ref} config (#6669).
-   Fix checking expiration of X.509 certificates (#6678).
-   Drop the lzma extra.
-   Fix JSON decoding errors when using MongoDB as backend (#6675).
-   Allow configuration of RedisBackend\'s health_check_interval
    (#6666).
-   Safeguard against schedule entry without kwargs (#6619).
-   Docs only - SQS broker - add STS support (#6693) through kombu.
-   Drop fun_accepts_kwargs backport.
-   Tasks can now have required kwargs at any order (#6699).
-   Min py-amqp 5.0.6.
-   min billiard is now 3.6.4.0.
-   Minimum kombu now is5.1.0b1.
-   Numerous docs fixes.
-   Moved CI to github action.
-   Updated deployment scripts.
-   Updated docker.
-   Initial support of python 3.9 added.