Rails 4 response_with включает ассоциацию с WHERE

Question

Я использую рельсы respond_with отправить ответ JSON клиенту, и я пытаюсь выяснить, как использовать includes вариант в respond_with вместе с where пункт в моей ассоциации

Вот мои модели:

class User < ActiveRecord::Base
   has_many :ratings
   has_many :movies, through: :ratings
end

class Rating < ActiveRecord::Base
   belongs_to :user
   belongs_to :movie
end

class Movie < ActiveRecord::Base
   has_many :ratings
   has_many :users, through: :ratings
end

В моем действии контроллера у меня есть:

def create
   movies = Movie.order("RANDOM()").limit(3)
   respond_with(movies, include: :ratings)
   // I'd like to do something like 
   // respond_with(movies, include: :ratings WHERE user: current_user)

end

Однако, это отвечает ВСЕМИ оценками для тех трех фильмов. Я хочу ограничить рейтинг только этого конкретного пользователя

Answer 1

Вы могли бы сделать это:

def create
  movies = Movie.order("RANDOM()").limit(3)
  # EDIT
  # movies = movies.merge(current_user.movies).includes(:ratings)
  movies = movies.joins(:ratings).merge(current_user.ratings).includes(:ratings)
  respond_with(movies)
end

Although that doesn't make much sense in a create действие.

НОТА

movies query above will generate the following SQL (2 commands; note that some of your fields will differ since I'm using bare versions of your models):

SELECT DISTINCT "movies"."id" FROM "movies" 
INNER JOIN "ratings" ON "ratings"."movie_id" = "movies"."id"
WHERE "ratings"."user_id" = ?  ORDER BY RANDOM() LIMIT 3

SELECT "movies"."id" AS t0_r0, "movies"."name" AS t0_r1, "movies"."created_at" AS t0_r2, 
"movies"."updated_at" AS t0_r3, "ratings"."id" AS t1_r0, "ratings"."user_id" AS t1_r1, 
"ratings"."movie_id" AS t1_r2, "ratings"."created_at" AS t1_r3, "ratings"."updated_at" AS t1_r4 
FROM "movies" INNER JOIN "ratings" ON "ratings"."movie_id" = "movies"."id" 
WHERE "ratings"."user_id" = ? AND "movies"."id" IN (1) ORDER BY RANDOM() [["user_id", 1]]