ruby-on-rails - Rails API : Adding array of objects to json return

Question

我在 Rails 5 中使用内置 API。

我正在学习使用 Rails 编写 API，并且我正在尝试弄清楚如何将属性添加到我的 json 返回值中，该属性是一个对象数组。

我有一个用户和帖子的模型。

我想做的是返回与用户相关的所有帖子。

我所做的是在 posts_controller.rb 中我有一个方法可以从 URL 获取用户 ID 并返回如下所示的 json:
[{"id":1,"content":"My first post!","user":{"id":1,"firstname":"Jody","lastname":"White","email":"t@t.com","fullname_firstname_first":"Jody White"}},{"id":2,"content":"Rails School is awesome!","user":{"id":1,"firstname":"Jody","lastname":"White","email":"t@t.com","fullname_firstname_first":"Jody White"}}]
但我想要的是返回如下所示:

{
    firstname: "Jody",
    lastname: "White",
    email: "whatever",
    posts: [{
        "id":1,"content":"My first post!"
        },
        {
            "id":2,"content":"Rails School is awesome!"
        }
    ]
}

我该怎么做，或者我可以让数据像这样返回吗？

用户.rb模型

class User < ApplicationRecord
  attr_accessor :fullname_firstname_first

  has_many :posts

  def fullname_firstname_first
    fullname_firstname_first = firstname + " " + lastname
  end
end

post.rb 模型

class Post < ApplicationRecord
  belongs_to :user
end

用户 Controller .rb

class UsersController < ApplicationController
  before_action :set_user, only: [:show, :update, :destroy]

  # GET /users
  def index
    @users = User.all
    render json: @users, include: :posts
  end

  # GET /users/1
  def show
    @user = User.find(params[:id])
    render json: @user, include: :posts
  end
end

Answer 1

假设你定义了这个结构:

class Post < ApplicationRecord
  belongs_to :user
end

class User < ApplicationRecord
  has_many :posts
end

您可以使用 Active Record 序列化方法实现您想要的结构 to_json .使用将在 respond_to阻止您的 Controller 。
format.json { render json: @users, include: :posts }
所以你的 UsersController看起来像这样:

class UsersController < ApplicationController
  def index
    # all users with all their posts 
    @users = User.all
    respond_to do |format|
      format.json { render json: @users, include: :posts }
    end
  end

  def show
    # single user and their posts
    @user = User.find(params[:id])
    respond_to do |format|
      format.json { render json: @user, include: :posts }
    end
  end
end

更新

而不是使用 repond_to块，您也可以使用:
render json: @users, include: :posts
您的 Controller 将如下所示:

class UsersController < ApplicationController
  def index
    # all users with all their posts 
    @users = User.all
    render json: @users, include: :posts
  end

  def show
    # single user and their posts
    @user = User.find(params[:id])
    render json: @user, include: :posts
  end
end