feat: JSON and YAML migration (Mapping -> Serializable)

[dukenguyenxyz]

• Resolves refactor: JSON.mapping -> JSON::Serializable #19
• Resolves feat: JSON emit_null option #14
• Resolves refactor: internal Missing type to not assigning instance var based on self.{{name.id}}_present? #25
• Allow for the following annotations in tags

[dukenguyenxyz]

optimised with present check

active-model/src/active-model/model.cr

Line 357 in 72ec666

def assign_attributes_from_trusted_json(json)

• Resolves refactor: internal Missing type to not assigning instance var based on self.{{name.id}}_present? #25

[dukenguyenxyz]

I will review and update this soon so we can pull this change in more quickly as 0.36.0 has officially dropped support for JSON/YAML.mapping

https://github.com/crystal-lang/crystal/releases/tag/0.36.0

[caspiano]

it was deprecated a while ago, that's why we use the json mapping shard. No rush.

[dukenguyenxyz]

spider-gazelle/rethinkdb-orm#21

This issue is actually very troublesome. Any sort of instance variable re-declaration in an inherited model will throw the error.

Edit:

This can be fixed if the child class instance_var / getter / setter / property does not redefine the TYPE

[stakach]

@dukeraphaelng what's the status of this pull?
still good to merge?

[stakach]

LGTM

[dukenguyenxyz]

yep this is good to go

@caspiano

[caspiano]

Waiting on resolution of this comment spider-gazelle/rethinkdb-orm#21 (comment)

[dukenguyenxyz]

specs failing due to Enum::ValueConverter update (merge) from master, generics out of scope. will look into this when I have time

edit: resolved!

[caspiano]

@dukeraphaelng could you please bring this up-to-date with master and check that placeos-models works (or can can be adjusted to support this)

[kimburgess]

Closing in favour of #34.