How to limit response fields for relationships?

[NaumenkoSergiy]

I'm interesting how to return all data, but limit some fields for specific relationships dynamically like this:

App::AgreementSerializer.new(
  @agreements,
  meta: pagy_pagination_metadata,
  fields: {
    organization: [:id, :slug, :name]
  }
)

[okuramasafumi]

@NaumenkoSergiy Could you provide the expected input and output?

[NaumenkoSergiy]

@okuramasafumi

For example: Agreement has one Organization, and Organizationserializer has next attributes:id, slug, name, logo, description`. But I want to have in response only specific fields from organization:

App::AgreementSerializer.new(
  @agreements,
  meta: pagy_pagination_metadata,
  fields: {
    organization: [:id, :slug, :name]
  }
)

=>

{
  id: 1,
  name: 'test',
  desciption: 'description',
  organization: {
    id: 1,
    slug: 'test',
    name: Test
  }
}

[okuramasafumi]

What is in your App::AgreementSerializer? It should return what's expected with the following code:

class App::AgreementSerializer
  include Alba::Resource

  attributes :id, :name, :description

  one :organization do
    attributes :id, :slug, :name
  end
end

[NaumenkoSergiy]

@okuramasafumi let's imagine that I have serializer what you provided. And sometimes I want to return only id for organization, or id and slug, not all attributes

[okuramasafumi]

I just wrote a test case for your use case.
https://github.com/okuramasafumi/alba/blob/main/test/usecases/field_selection_test.rb

Basically what we do here is to add another custom DSL to Alba. You can try this out and see how it goes. Let me know if you have some trouble.