Rails 6 API 仅不保存嵌套属性

Question

我有一个 Rails 6 应用程序，它作为移动应用程序的后端提供程序在 API 仅模式下工作。

我有两个模型 Offer 和 ServiceContent

class Offer < ApplicationRecord
  belongs_to :user
  has_many :service_contents
  accepts_nested_attributes_for :service_contents, allow_destroy: true

  #..... much more stuff below here
end

class ServiceContent < ApplicationRecord
  belongs_to :offer
end

我的 OffersController 看起来像这样：

# frozen_string_literal: true

class OffersController < ApplicationController
  before_action :set_offer, only: %i[show update destroy]
  before_action :authenticate_user, only: %i[create show update destroy]

 
  def new
    @offer = Offer.new
    @offer.service_contents.build
  end
  

  # POST /offers
  # POST /offers.json
  def create
    @offer = Offer.new(offer_params)


    if @offer.save
      render :show, status: :created, location: @offer
    else
      render json: @offer.errors, status: :unprocessable_entity
    end
  end

  # PATCH/PUT /offers/1
  # PATCH/PUT /offers/1.json
  def update
    if @offer.update(offer_params)
      render :show, status: :ok, location: @offer
    else
      render json: @offer.errors, status: :unprocessable_entity
    end
  end

  # DELETE /offers/1
  # DELETE /offers/1.json
  def destroy
    @offer.destroy
  end


  private


  # Use callbacks to share common setup or constraints between actions.
  def set_offer
    @offer = Offer.find(params[:id])
  end

  # Never trust parameters from the scary internet, only allow the white list through.
  def offer_params
    params.require(:offer).permit(:id,
                                  :from,
                                  :to,
                                  :departure_datetime,
                                  :return_datetime,
                                  service_contents_attributes: [:name, :icon_id, :data]
                                  )

    # params.fetch(:offer, {})
  end


end

当我想通过 Postman 创建这个时，问题就出现了。

我的 JSON 看起来像这样：

{
    "from": "Maroco, Maroco",
    "to": "Zagreb, Croatia",
    "departure_datetime": "2020-09-05 14:32:45 +0200",
    "user_id": 1,
    "service_contents": [
        {
            "name": "test",
            "icon_id": 1,
            "data": null
        },
        {
            "name": "itd",
            "icon_id": 2,
            "data": 0
        }
    ]
}

我通过POST方法发送数据，params明明通过了，但是ServiceContent总是创建为一个空数组。

Started POST "/offers/" for ::1 at 2020-09-05 14:52:56 +0200
Processing by OffersController#create as */*
  Parameters: {"from"=>"Maroco, Maroco", "to"=>"Zagreb, Croatia", "departure_datetime"=>"2020-09-05 14:32:45 +0200", "user_id"=>1, "service_contents"=>[{"name"=>"test", "icon_id"=>1, "data"=>nil}, {"name"=>"itd", "icon_id"=>2, "data"=>0}], "offer"=>{"from"=>"Maroco, Maroco", "to"=>"Zagreb, Croatia", "departure_datetime"=>"2020-09-05 14:32:45 +0200", "user_id"=>1}}
  User Load (0.4ms)  SELECT "users".* FROM "users" WHERE "users"."id" =  LIMIT   [["id", 1], ["LIMIT", 1]]
  ↳ app/controllers/application_controller.rb:21:in `refresh_bearer_auth_header'
  CACHE User Load (0.0ms)  SELECT "users".* FROM "users" WHERE "users"."id" =  LIMIT   [["id", 1], ["LIMIT", 1]]
  ↳ app/controllers/offers_controller.rb:34:in `create'
  TRANSACTION (0.1ms)  BEGIN
  ↳ app/controllers/offers_controller.rb:34:in `create'
  Offer Create (0.6ms)  INSERT INTO "offers" ("from", "to", "departure_datetime", "user_id", "created_at", "updated_at", "offer_type_icon") VALUES (, , , , , , ) RETURNING "id"  [["from", "Maroco, Maroco"], ["to", "Zagreb, Croatia"], ["departure_datetime", "2020-09-05 12:32:45"], ["user_id", 1], ["created_at", "2020-09-05 12:52:56.689955"], ["updated_at", "2020-09-05 12:52:56.689955"], ["offer_type_icon", 2]]
  ↳ app/controllers/offers_controller.rb:34:in `create'
  TRANSACTION (0.9ms)  COMMIT
  ↳ app/controllers/offers_controller.rb:34:in `create'
  Rendering offers/show.json.jbuilder
  ServiceContent Load (0.3ms)  SELECT "service_contents".* FROM "service_contents" WHERE "service_contents"."offer_id" =   [["offer_id", 6]]
  ↳ app/views/offers/_offer.json.jbuilder:10
  Rendered offers/_offer.json.jbuilder (Duration: 7.9ms | Allocations: 2087)
  Rendered offers/show.json.jbuilder (Duration: 8.7ms | Allocations: 2234)
Completed 201 Created in 66ms (Views: 10.2ms | ActiveRecord: 19.7ms | Allocations: 19234)

自从我收到回复后，它显然将内容保存到数据库中：

{
    "id": 6,
    "from": "Maroco, Maroco",
    "to": "Zagreb, Croatia",
    "departure_date": "2020-09-05",
    "departure_time": "12:32",
    "offer_type_icon": 2,
    "service_contents": []
}

但正如我所说，service_contents 始终是一个空数组。

感谢任何帮助。

Answer 1

好的，我实际上找到了答案。

感谢@dbugger 指出了一个好的方向。

在检查了 jbuilder 之后，我发现这不是真正的问题。

发送嵌套参数时，Rails 期望它们的名称中始终添加 _attributes -> https://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html

所以代替：

{
    "from": "Maroco, Maroco",
    "to": "Zagreb, Croatia",
    "departure_datetime": "2020-09-05 14:32:45 +0200",
    "user_id": 1,
    "service_contents": [
        {
            "name": "test",
            "icon_id": 1,
            "data": null
        },
        {
            "name": "itd",
            "icon_id": 2,
            "data": 0
        }
    ]
}

这需要有：

{
    "from": "Maroco, Maroco",
    "to": "Zagreb, Croatia",
    "departure_datetime": "2020-09-05 14:32:45 +0200",
    "user_id": 1,
    "service_contents_attributes": [
        {
            "name": "test",
            "icon_id": 1,
            "data": null
        },
        {
            "name": "itd",
            "icon_id": 2,
            "data": 0
        }
    ]
}

这样它可以正常创建东西并将其保存到数据库中。

希望它能在将来使某人免于头痛。

Rails 6 API 仅不保存嵌套属性

Rails 6 API only doesn't save nested attributes

api

json

ruby-on-rails

rails-api

ruby-on-rails-6