class Deerjikist < ApplicationRecord self.primary_key = :platform, :code belongs_to :tag validates :platform, presence: true validates :code, presence: true validates :tag_id, presence: true validate :tag_must_be_deerjikist enum :platform, nico: 'nico', youtube: 'youtube' private def tag_must_be_deerjikist if tag && !(tag.deerjikist?) errors.add :tag, 'タグはニジラー・カテゴリである必要があります.' end end end