Make JSONField support type annotation and OpanAPI document generation

[LanceMoe]

Make JSONField support type annotation and OpanAPI document generation

JSONField adds optional generic support, and supports OpenAPI document generation by specifying field_type as a pydantic BaseModel

Description

JSONField is defined as Any, which does not display properly when using FastAPI to automatically generate OpenAPI documents. #1702
This PR did two things:

• Manually specifying field_type enabled the document to be generated properly.
• Python generics allow for better type hints in IDEs (Pylance and Mypy).

Motivation and Context

I have been using FastAPI + tortoise-orm as the preferred solution for all my project.
My project front-end uses TypeScript + React, and uses openapi-typescript to automatically convert the OpenAPI document generated by FastAPI into a type that can be used by TypeScript. However, the JSONField of tortoise-orm does not support type hints, which requires a lot of type cast in my front-end code, so I tried to add type support to JSONField.

How Has This Been Tested?

In my project, it works correctly, so I'm going to submit a PR to see if it helps with tortoise-orm. But I'm not sure if it will pass the existing tests. I'd like to add as many tests as possible, and hope to get help from the project maintainers.
(Now I have added some test cases for this PR.)

Screenshots of my project:

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added the changelog accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[LanceMoe]

I built a local test environment and changed some code to ensure that the change was compatible with the previous version.
I also added relevant tests and documentation.

[LanceMoe]

I fixed some code so that it now should pass mypy check (make lint).

[abondar]

@LanceMoe Hi!

Please check out CI - seems like tests are failing

[LanceMoe]

@abondar
Thanks for your reply, I had only tested it in python 3.10 before and it worked fine. I just set up the test and it does fail in python 3.8 and 3.9, the reason is because staticmethod is not considered callable before python 3.10.
Now I fixed the test and it should work in older versions of python now.
Please try running CI again, thanks!

but Codacy Static Code Analysis throw a problem, the lambda is unnecessary on python >= 3.10, but is necessary for python <= 3.9

So I had to move it outside class

[coveralls]

Pull Request Test Coverage Report for Build 11882530003

Details

• 44 of 49 (89.8%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.02%) to 89.254%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tortoise/fields/data.py	24	29	82.76%

Totals
Change from base Build 11881509020:	-0.02%
Covered Lines:	6224
Relevant Lines:	6857

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💛 - Coveralls