Rails - `before_action` in inheritance • Tuan Tran

Everbody know what before_action do, but today, I find some interesting thing with before_action in inheritance.

For example:

class Api::V1::BooksController < Api::V1::BaseController
  before_action :authenticate_user, only: %i(create update)

  def create
    # stuff here
  end

  def update
    # stuff here
  end
end

class Api::V2::BooksController < Api::V1::BooksController
  before_action :authenticate_user, only: :show

  def show
    # ...
  end
end

I wanna call authenticate_user for both method: show in ChildController and create, update for ParentController, but if I write code like above, authenticate_user will be called ONLY for action show. If POST request comes from: /api/v2/books, authenticate_user will NOT be called.

Solution

Call the method inside a block inside child controller instead of passing it by name.

class Api::V2::BooksController < Api::V1::BooksController
  before_action(only: :show){authenticate_user}

  def show
    # ...
  end
end