Issue 1:
Checklist

I have verified that the issue exists against the master branch of Celery.

This has already been asked to the discussion group first.

I have read the relevant section in the

contribution guide

on reporting bugs.

I have checked the issues list

for similar or identical bug reports.

I have checked the pull requests list

for existing proposed fixes.

I have checked the commit log

to find out if the bug was already fixed in the master branch.

I have included all related issues and possible duplicate issues

in this issue (If there are none, check this box anyway).

Mandatory Debugging Information

I have included the output of celery -A proj report in the issue.

(if you are not able to do this, then at least specify the Celery

version affected).

I have verified that the issue exists against the master branch of Celery.

I have included the contents of pip freeze in the issue.

I have included all the versions of all the external dependencies required

to reproduce this bug.

Optional Debugging Information

I have tried reproducing the issue on more than one Python version

and/or implementation.

I have tried reproducing the issue on more than one message broker and/or

result backend.

I have tried reproducing the issue on more than one version of the message

broker and/or result backend.

I have tried reproducing the issue on more than one operating system.

I have tried reproducing the issue on more than one workers pool.

I have tried reproducing the issue with autoscaling, retries,

ETA/Countdown & rate limits disabled.

I have tried reproducing the issue after downgrading

and/or upgrading Celery and its dependencies.

Related Issues and Possible Duplicates

Related Issues

I use mongo broker and mongo backend.

There is a decoding error while try to get task result with AsyncResult

File "task_result.py", line 9, in <module> print(res.result) ...... \python37-32\Lib\json\__init__.py", line 341, in loads raise TypeError(f'the JSON object must be str, bytes or bytearray, ' kombu.exceptions.DecodeError: the JSON object must be str, bytes or bytearray, not dict

tasks.py

> @celery.task(name='web.add', bind=True)
> def add_test(self, x):
> time.sleep(6)
> message = 'IN WORKER'
> self.update_state(state='PROGRESS', meta={ 'current': 50, 'total': 100, 'status': message})
> time.sleep(10)
> message = 'END'
> return { 'current': 100, 'total': 100, 'status': message, 'result': { 'video_url': 42, 'video_player_url' : 'https://invidza.com' } }

task_result.py

>res = add.AsyncResult('d6605146-9296-463f-9463-9795d6b87f37')
>print(res)
>print(res.result)

Possible Duplicates

None

Environment & Settings

Celery version:

celery report Output:

Steps to Reproduce

Required Dependencies

Minimal Python Version: N/A or Unknown

Minimal Celery Version: N/A or Unknown

Minimal Kombu Version: N/A or Unknown

Minimal Broker Version: N/A or Unknown

Minimal Result Backend Version: N/A or Unknown

Minimal OS and/or Kernel Version: N/A or Unknown

Minimal Broker Client Version: N/A or Unknown

Minimal Result Backend Client Version: N/A or Unknown

Python Packages

pip freeze Output:

Other Dependencies

N/A

Minimally Reproducible Test Case

Expected Behavior

result = {'current': 50, 'total': 100, 'status': 'IN WORKER'}

Actual Behavior

Issue 2:
Checklist

[x ] I have checked the issues list

for similar or identical bug reports.

[ x] I have checked the pull requests list

for existing proposed fixes.

[x ] I have checked the commit log

to find out if the bug was already fixed in the main branch.

[ x] I have included all related issues and possible duplicate issues in this issue

(If there are none, check this box anyway).

Related Issues and Possible Duplicates

Related Issues

None

Possible Duplicates

None

Description

I have couple of questions about the backends-and-brokers page.

I see under RabbitMQ note, it is written,

If more guaranteed long-term persistence is needed from the result store, consider using PostgreSQL or MySQL (through SQLAlchemy).

Whereas under SQLAlchemy it is written,

Historically, SQLAlchemy has not been the most stable result backend so if chosen one should proceed with caution.

IMO, these are either two conflicting statements. IMO, The second statement is inaccurate & misleading considering the fact that SQLAlchemy ORM has developed a lot and is very stable. We have been using Airflow + Celery + MySQL as a result backend for more than four years without a single issue. We have been using the open-source tool Apache Superset which is totally dependent on SQLAlchemy and there are no major or consistent issues reported with SQLAlchemy in that project as well.

IMO, SQLAlchemy should not be considered a non-stable result backend.

There is no configuration reference URL for SQLAlchemy like it is present for other backends. I think we can add a reference to this configuration page section.

Suggestions

If you agree then I am happy to raise a PR to remove this line from the doc.

Historically, SQLAlchemy has not been the most stable result backend so if chosen one should proceed with caution.

and add the above-said configuration doc reference for SQLAlchemy.

You just have to let me know which GitHub file in this repo I have to update.