Question

我正在尝试在Rails 5中学习一些关于ActiveModelSerializers的内容。我正在关注此tutorial并遇到一些错误：

我可能不应该乱用Rails 5 beta吗？

rails -v
Rails 5.0.0.beta3

和Ruby：

ruby -v
ruby 2.2.4p230 (2015-12-16 revision 53155) [x86_64-darwin15]

这是我的架构：

ActiveRecord::Schema.define(version: 20160303205439) do

  create_table "rental_units", force: :cascade do |t|
    t.string   "address"
    t.integer  "rooms"
    t.integer  "bathrooms"
    t.integer  "price_cents"
    t.datetime "created_at",  null: false
    t.datetime "updated_at",  null: false
    t.integer  "user_id"
  end

  add_index "rental_units", ["user_id"], name: "index_rental_units_on_user_id"

  create_table "users", force: :cascade do |t|
    t.string   "name"
    t.datetime "created_at", null: false
    t.datetime "updated_at", null: false
    t.string   "email"
  end

end

这是我的种子：

User.create(name: "1st user", email: "1stemail@gmail.com")
User.create(name: "2nd user", email: "2ndemail@gmail.com")
User.create(name: "3rd user", email: "3rdemail@gmail.com")

RentalUnit.create(address: "1st address", rooms: 2, bathrooms: 2, price_cents: 50000, user_id:1)
RentalUnit.create(address: "2nd address", rooms: 2, bathrooms: 2, price_cents: 50000, user_id:1)
RentalUnit.create(address: "3rd address", rooms: 2, bathrooms: 2, price_cents: 50000, user_id:1)
RentalUnit.create(address: "4th address", rooms: 2, bathrooms: 2, price_cents: 50000, user_id:2)

这是我的RentalUnit模型：

class RentalUnit < ApplicationRecord
end

这是我的RentalUnitSerializer：

class RentalUnitSerializer < ActiveModel::Serializer
  attributes :id, :address, :rooms, :bathrooms, :price, :price_per_room
  belongs_to :user
end

当我尝试运行rails服务器时，我得到：

rs
=> Booting Puma
=> Rails 5.0.0.beta3 application starting in development on http://localhost:3000
=> Run `rails server -h` for more startup options
=> Ctrl-C to shutdown server
Exiting
/Users/Jwan/Dropbox/programming/rails/api_codeship/app/serializers/rental_unit_serializer.rb:3:in `<class:RentalUnitSerializer>': undefined method `belongs_to' for RentalUnitSerializer:Class (NoMethodError)
    from /Users/Jwan/Dropbox/programming/rails/api_codeship/app/serializers/rental_unit_serializer.rb:1:in `<top (required)>'
...

知道发生了什么事吗？

有没有关于API设计，Rails API和AMS的任何有用的教程？

Answer 1

您的has_one模型（也可能是has_many模型）中缺少RentalUnit或User关系。在您的belongs_to :user模型中添加RentalUnit，在has_one模型中添加has_many或User，具体取决于您的需求。

我正在使用Rails 5beta2和ActiveModel Serializer，它工作正常......猜测beta3应该只会更好。

Rails 5和ActiveModelSerializers

1 个答案: