has_many通過具有自定義類型的多態

Question

我有2個應用程序，一個作為API並具有只讀訪問權限，另一個是主要應用程序。 在主應用程序中，我有一個通過多態的關系。 主應用程序中的模型看起來像這樣，並且運行良好：

class Category < ActiveRecord::Base
  has_many :category_associations
  has_many :posts, through: :category_associations
  has_many :pages, through: :category_associations
end

class Post < ActiveRecord::Base
  has_many :category_associations, as: :associated
  has_many :categories, as: associated, through: :category_associations, source: :post
end

class Page < ActiveRecord::Base
  has_many :category_associations, as: :associated
  has_many :categories, as: associated, through: :category_associations, source: :post
end

class CategoryAssociation
  belongs_to :category
  belongs_to :associated, polymorphic: true
end

現在，對於第二個應用程序，我將需要訪問相同的表，但是我的類名將有所不同，這會影響即使使用source_type也無法覆蓋的type字段：

class Category < ActiveRecord::Base
  has_many :category_associations
  has_many :articles, through: :category_associations
  has_many :static_contents, through: :category_associations
end

class Article < ActiveRecord::Base
  self.table_name = 'posts'

  has_many :category_associations, as: :associated
  has_many :categories, as: associated, through: :category_associations, source: :article, source_type: 'Post'
end

class StaticContent < ActiveRecord::Base
  self.table_name = 'pages'

  has_many :category_associations, as: :associated
  has_many :categories, as: associated, through: :category_associations, source: :static_content, source_type: 'Page'
end

class CategoryAssociation
  belongs_to :category
  belongs_to :associated, polymorphic: true
end

我收到以下錯誤：

=> Posts.first.categories

# ActiveRecord::HasManyThroughAssociationPointlessSourceTypeError: Cannot have a has_many :through association 'Post#categories' with a :source_type option if the 'CategoryAssociation#category' is not polymorphic. Try removing :source_type on your association.

似乎當我從該類別中獲取帖子時

Answer 1

您是否嘗試過將polymorphic:true放到分類belongs_to ？ 似乎這是錯誤消息指向的方向，盡管我不確定

class CategoryAssociation
  belongs_to :category, polymorphic: true
  ...
end