✨ Add `SimpleJSONResponse` for decimal JSON encoding

[tomy0000000]

As mentioned in #4998. I believe simplejson is the best option to accomplish high decimal points real number encoding, hence the need of SimpleJSONResponse. I followed some of the parameters used in starlette's original JSONResponse here to make sure the output are the most consistent as possible.

If interested, I'm also willing to draft a page of doc detailing the best practice of handling decimal in FastAPI I've come up so far. Just let me know if that's something you'd like to include.

[codecov[bot]]

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[github-actions[bot]]

📝 Docs preview for commit abf736a6ff5f18ff30af2b90721f7773389b9aab at: https://62a4c36223b63b38e9736ac6--fastapi.netlify.app

[github-actions[bot]]

📝 Docs preview for commit 1bbee018e2596e010842d05654e6f8130dfd1729 at: https://62a4c5ed1ac5a03f5530312d--fastapi.netlify.app

[odiseo0]

Maybe you can make some tests and write some docs too

[github-actions[bot]]

📝 Docs preview for commit 96e3b5f071f6e95287c63bf65a1a2183a41c75c6 at: https://62ab81ec445265209b184aea--fastapi.netlify.app

[tomy0000000]

Hi folks,

as suggested, I've written a page detailing on how to make use of simpleJSONResponse and also some tips on how to make Decimal works with FastAPI.

This is my first time authoring a complete doc for open source project, feedbacks are welcomed 👍🏻

[github-actions[bot]]

📝 Docs preview for commit a837c23094794a5b8ccb4b2cb7ae6a1a8fdb9e15 at: https://62da846ddace10066081dd5e--fastapi.netlify.app

[theRealSuperMario]

I could really use this ASAP. Any chance this will get merged soon?

[tomy0000000]

@tiangolo Would you mind taking a minute to review this? Docs and tests ready, reviewed by others.

[tiangolo]

Thank you @tomy0000000! 🍰

Nevertheless, instead of providing another type of response, I prefer to teach people how to create their own, in particular when creating a new response takes an effort equivalent to learning a new one included, also as not everyone will need it, but if it's included, everything learning could expect to need to learn it. And as it's around 2 or 3 lines of code, I prefer to teach how to use it: https://fastapi.tiangolo.com/advanced/custom-response/#custom-response-class

But you could, for example, write a blog post about using decimal values in JSON responses with your use case, and how to create the SimpleJSONResponse. 🤓

For now, I'll pass on this one, but thanks for the effort! ☕