Splitting json adapter into two

[joaomdmoura]

We discussed about the root option and how it shouldn't be a config but a different adapter itself.

This PR create a FlattenJson adapter that doesn't support root, the Json adapter in the other hand will now have root by default and you will still be able to manually set it with the root option.

FlattenJson is now the default adapter, the result still will be the same we had before, when the default was Json adapter without root.

[spastorino]

Last tiny bit ...

curl http://localhost:3000/todos
{"todo":[{"id":1,"title":"Todo 1","completed":false,"order":1},{"id":3,"title":"Todo 8","completed":true,"order":2}]}

We would need that one the be todos as it was in old AMS, that's the way it plays nice with Ember's Rest adapter.

[joaomdmoura]

@spastorino done.

• Removed root option (removed the tests related to it)
• Pluralizing root when using ArraySerializer

btw, as I mentioned there is no need to store the result for now.

[spastorino]

curl http://localhost:3000/todos
{"todo":[{"id":1,"title":"Todo 1","isCompleted":null}]}

[joaomdmoura]

@spastorino 😢 tested over here:
(you can check the code here)

Can you share ur controller code?
Did you defined ActiveModel::Serializer.config.adapter = :json?
Is it pointed to the last commit?

curl http://localhost:3000

{ 
  "posts": [
    {"id":1,"title":"Awesome Post","body":"Indeed a great one!","user":{"id":2,"name":"Mattew Crazy","age":33,"email":"mattew@crazy.com"}},
    {"id":2,"title":"Incredible Post","body":"Indeed another great one!","user":{"id":2,"name":"Mattew Crazy","age":33,"email":"mattew@crazy.com"}}
  ]
}

[bf4]

This is a pretty big change. Prior to this, the root option always went to the adapter. Now it will always go to the serializer. Which code path should be dead? root to serializer or root to adapter?

[joaomdmoura]

Yeah @bf4 this is indeed a big change.
The idea is that root shouldn't be an option, but another adapter by itself.
This make it even easier to integrate with some js frameworks.
We also removed the option to set a specific root key, so the root isn't "going" to the serializer, but is the serializer the one that knows what it should be and the adapter the one the uses it or not.

[bf4]

I'll have to read through the code some more to make sure I understand the changes as they affect tests that were deleted or whose expectations were changed. It didn't break #954 (once I rebased it), but I think this is the kind of thing we should include in the README between 'how it works' and 'intended usage'...

[joaomdmoura]

Yeah, we realized we forgot about the README, but I'm already updating it.
I'm glad it didn't broke #954 😄