`undefined method 'id' for nil:NilClass` when include null none primary key association

create_join_table :members, :articles, {id: false} do |t|
  t.integer :article_id
  t.string :polymorphicable_type
  t.integer :polymorphicable_id
end

class MemberArticles < ApplicationRecord
   belongs_to :article
   belongs_to :polymophicable, polymorphic: true
end
class ArticleRecourse < JSONAPI::Resource
  has_many :members, always_include_linkable_data: true
end

I want serialize articles polymorphic data througth join_table associated

when i use always_include_linkable_data: true or direct serialize members model also throw this exception.

should each resource model entity at least have _primary_key or id method? it is jsonapi-resources convention? If true, Maybe write in documents

Reproduce the supplied Rails join-table and polymorphic-association example, starting at serialization of members with always_include_linkable_data enabled. Trace why the associated resource reaches the missing id method, then determine whether resources without a primary key are supported. Done means the behavior is corrected or the supported requirement is clearly documented.