JSON Patch

I quite like JSON Patch but I've always felt that it's so convoluted only because of its goal of being able to modify every possible JSON document under the sun. If you allow yourself to restrict your data set slightly, you can patch documents much simpler.

For example, Firebase doesn't let you store null values. Instead, for Firebase, setting something to null means the same as deleting it. With a single simple restriction like that, you can implement PATCH simply by accepting a (recursive) partial object of whatever that endpoint. Eg if /books/1 has

    { title: "Dune", score: 9 }

you can add a PATCH /books/1 that takes eg

    { score: null, author: "Frank Herbert" }

and the result will be

    { title: "Dune", author: "Frank Herbert" }

This is way simpler than JSON Patch - there's nothing new to learn, except "null means delete". IMO "nothing new to learn" is a fantastic feature for an API to have.

Of course, if you can't reserve a magic value to mean "delete" then you can't do this. Also, appending things to arrays etc can't be done elegantly (but partially mutating arrays in PATCH is, I'd wager, often bad API design anyway). But it solves a very large % of the use cases JSON Patch is designed for in a, in my humble opinion, much more elegant way.

> I quite like JSON Patch but I've always felt that it's so convoluted only because of its goal of being able to modify every possible JSON document under the sun.

It seems like this is mainly a problem if you're implementing this _ad hoc_ on the client or server side -- is that right?

I mean: presumably most of the time that you want to either of these, you already have both the old and new object, right? Is it not straightforward to write a function (or library) that takes two plain objects and generates the JSON Patch from one to the other, and then use that everywhere and not think about this (but retain the advantage of "being able to modify every possible JSON document under the sun").

If there are cases where you're making a delta without the original object (i.e., I know I always want to remove one field and add some other, whatever the original state was), it seems like you could have nice helpers like `JsonPatch::new().remove_field('field1').add_field('field2', value)`.

I haven't actually done this so maybe I'm missing something about how you want to use these things in practice?

edit to add my motivation: I'd much rather having something robust and predictable, even if it means writing tooling to make it convenient, than something that _seems_ easy but then can't handle some cases or does something different than expected ("I wanted this to be null, not gone!").