fix jsonb parse after get value from database

[sillydong]

In my development environment, the UserPreference will always return value as str although it is set to JSONBField.

I dig deeper and found the model of django needs from_db_value to do the type convert job.

So added this function for JSONField to support auto convert. Please kindly review this. Thanks!

VERSIONS:
Python == 3.7.10
django == 3.2.4
djangorestframework == 3.12.4
djangorestframework-bulk == 0.2
djangorestframework-filters == 1.0.0.dev2
django-admin-bootstrapped == 2.5.6
django-bootstrap3 == 11.1.0
django-filter == 2.4.0

[jdetaeye]

FrePPLe needs a customized version of django 2.2: see

frepple/requirements.txt

Line 21 in a2b3831

https://github.com/frePPLe/django/tarball/frepple_6.0

However, I see you have "django == 3.2.4".

Until we upgrade to a newer django version, I prefer not merge this pull request. With such an upgrade we'd probably migrate to django's standard jsonfield rather than keeping the current customized one.

[sillydong]

@jdetaeye Thanks for your reply.

As I'm building it from source. I didn't use code from https://github.com/frePPLe/django/tarball/frepple_6.0. So the default installed version for django is 3.2.4. I'll try downgrade it.

However, this fix can be used later when you upgrade django to 3.x.x version. I guess this may still be useful.

[sillydong]

Also, I'm trying the source code with django == 3.1.12, a little earlier than the latest version. If you have plan to upgrade it. I can also provide modifications for compatibility.

[jdetaeye]

The correct way to install the dependencies is to install all with pip:
pip3 install -r https://raw.githubusercontent.com/frepple/frepple/6.14.0/requirements.txt
Simple and easy, and it will install the customized version of django.
You can install in a virtualenv if you don't want to mix up your default python installation.

We have no short term plans to upgrade django. Django 2.2 is an LTS release supported till next spring - see https://www.djangoproject.com/download/

If you work on upgrading django, you need to check out all our customizations on top of 2.2.17: you can see those on https://github.com/frePPLe/django/commits/frepple_6.0 These customizations are really important for frepple to work correctly.

[sillydong]

Thanks a lot

[sillydong]

Thanks a lot

[jdetaeye]

Closing this pull request. We are currently working on the upgrade from django 2.2 to django 3.2. Your pull request provided input for a part of the required code changes. Many thanks for the input!!!