sort by country that is related to resource not directly but through the third relation is not work properly

まず、issue に示されている Routing::Destination、DestinationResource、System::NetworkPrefix の関連付けを使って GET /destinations?sort=country.name を再現します。生成された SQL と、ソートにおけるリレーション結合のエントリーポイントを調査します。間接的な country の関連付けによるソートが、存在しない destinations.country_id カラムを参照しなくなり、リクエストが正常に完了すれば完了です。

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Description

When making a request to a specific API endpoint with the query parameter sort=country.name, the application crashes due to an error in the sorting mechanism. The problem arises because the country relationship does not directly belong to the destination model but rather through another association. This leads to an undefined column error when attempting to perform the sorting operation.

Additional info

class Routing::Destination < ApplicationRecord
  belongs_to :network_prefix, class_name: 'System::NetworkPrefix', optional: true
  has_one :country, through: :network_prefix
end

class Api::Rest::Admin::Routing::DestinationResource < JSONAPI::Resource
  has_one :country, class_name: 'Country', force_routed: true, foreign_key_on: :related
end

class System::NetworkPrefix < ApplicationRecord
  belongs_to :country, class_name: 'System::Country', foreign_key: :country_id, optional: true
end

request that lead to 500 error
GET /destinations?sort=country.name

SELECT "class4"."destinations".* FROM "class4"."destinations"
LEFT JOIN sys.countries AS country_sorting ON country_sorting.id = class4.destinations.country_id
LEFT JOIN class4.rate_groups AS rate_group_sorting ON rate_group_sorting.id = class4.destinations.rate_group_id
ORDER BY country_sorting.name asc, rate_group_sorting.name asc LIMIT $1 OFFSET $2  [["LIMIT", 50], ["OFFSET", 0]]


Internal Server Error: PG::UndefinedColumn: ERROR:  column destinations.country_id does not exist
LINE 1: ...ntries AS country_sorting ON country_sorting.id = class4.des...
                                                             ^

jsonapi-resource version 0.9.12