仕事で GraphQL を使ったプロダクトに DDD のエッセンスを取り入れたく、GraphQL で部分的にフェッチしたドメインモデルに堅牢な型付けを試みたので、まだまだ荒削りですが紹介します。 やりたいこと このような GraphQL スキーマがあったとします。 type Person { firstName: String! lastName: String! age: Int! } type Query { person: Person! } function getAnnotatedFullName(person: Person): string { const suffix = isAdult(person) ? "" : " (未成年)" return person.firstName + " " + person.lastName + suffix; } function i
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