Alba nested_attribute support

[pgiblock]

Thanks for the awesome library! Combined with your alba-inertia, it is making my recent Vue/Inertia/Rails project a type-safe breeze.

I did just run into a problem though, and that's with Alba's nested attribute feature:

class Activities::Templates::IndexResource
  include Alba::Resource
  include Alba::Inertia::Resource
  include Typelizer::DSL

  typelize :boolean
  attribute test {|x| false}

  nested_attribute :nested do
    typelize :string
    attribute test1 {|x| "hello"}

    typelize :string
    attribute test2 {|x| "world"}
  end
end

This produces:

type ActivitiesTemplatesIndex = {
  test: boolean;
  nested: unknown;
}

Not sure exactly what I was expecting, but likely another type, similar to how typelizer handles traits.

[skryukov]

Thanks @pgiblock, awesome to hear!

Could you try replacing include Typelizer::DSL and include Alba::Inertia::Resource with helper Typelizer::DSL and helper Alba::Inertia::Resource?

Source: https://github.com/okuramasafumi/alba?tab=readme-ov-file#helper

[pgiblock]

Thanks for getting back so quick @skryukov - I just tried that and it doesn't help. I also tried adding another pair of include or helper into the nested_attribute block - but that didn't help. Everything serializes just fine -- but typelizer doesn't seem to know what to do with the nested_attribute itself. I've tried with versions 0.7.0 and 0.8.0.

Looking at the code here, it seems like it makes an untyped property: https://github.com/skryukov/typelizer/blob/main/lib/typelizer/serializer_plugins/alba.rb#L166 But, I'd think it would need to do more like what is done with traits: run a collector over an evaluation of the block, produce a new type with those properties or emit them as a nested type.

[pgiblock]

I had some success with enhancing the nested attributes support. I should have a PR soon

[pgiblock]

The problem with typelize DSL in Alba nested is due to how they instantiate the class. For traits, it is the provided resource, but for nested it is a Class.new(Alba::Resource). The only way I can get around that is by monkey patching Alba itself - to either pull in Typelizer::DSL or to stub it out with a no-op typelizer since it has no effect at render time anyway. Therefore, I have filed a bug with them and a suggested fix: okuramasafumi/alba#495

However, there was still a lot to improve with typelizer itself to enhance support for nested attributes. Please see PR #90

[pgiblock]

Thanks for pulling in the PR. Newer versions look good to me. Well, except I found an issue that seems to be across nested as well as traits:

If you've configured a properties_transformer (I've tested globally, but I presume it would affect per-writer configuration as well): then properties of these subtypes are not rewritten. Looking at the code, I see one place where properties_transformer is invoked, but it looks like traits et do their own thing. I'm not sure if it is best to just wedge that in all over or if we want to pull out a utility to use across the board.