Rails 4 - belong_to 嵌套对象字段未保存

Question

注意：我读过一些与此类似的帖子。但是没有一个解决方案适合我。
我有两个具有一对多关系的对象 Appeal 和 Appealer。当我保存上诉对象时，所有字段都被保存，上诉者 ID 也被保存（作为 FK）。但是在 Appealer table 中保存了一条新记录，除了 id 之外没有任何数据。

型号

class Appeal < ActiveRecord::Base
    belongs_to :appealer, :autosave => true
    accepts_nested_attributes_for :appealer
end

class Appealer < ActiveRecord::Base
    has_many :appeals, :autosave => true
end

上诉控制器

class AppealsController < ApplicationController
    def index
        respond_with Appeal.all
    end

    def create
        appealer = Appealer.create(appealer_params)
        @appeal = Appeal.create(appeal_params)
        @appeal.appealer = appealer


        if @appeal.save
          respond_with @appeal
        else
          respond_with {:error}
        end
    end

    def show
        respond_with Appeal.find(params[:id])
    end

    private
    def appeal_params
        params.require(:appeal).permit(:subject, :status, :submit_means, :card_type, :submit_date, :relationship, :report_date, :explanation, :email_approval)
    end
    def appealer_params
        params.require(:appeal).permit(appealer: [:appealer_id, :first_name, :last_name])
    end
end

编辑这是我使用的json

{
        "id": 21,
        "subject": "axxxscaaaa",
        "status": "happy",
        "submit_means": "DOAR",
        "card_type": "sdsd",
        "submit_date": 1466629200000,
        "relationship": null,
        "report_date": 1466542800000,
        "explanation": "sdsd",
        "email_approval": null,
        "appealer": {"first_name":"aaaaaaa", "last_name":"fffff"},
        "selfRequest": false,
        "created_at": 1465851600000,
        "updated_at": 1465333200000
    }

不明白为什么申诉人的字段没有保存

Answer 1

试试这个

def appeal_params
   params.require(:appeal).permit(:subject, :status, :submit_means, :card_type, :submit_date, :relationship, :report_date, :explanation, :email_approval, appealers_attributes: [:id, :first_name, :last_name] )
end

并删除此行 appealer = Appealer.create(appealer_params)

Answer 2

当您 JSON 显示对象时，您没有使用 rails fields_for 或视图表单上的其他内容。因此，您的模型中不需要此（ accepts_nested_attributes_for :appealer ）行。模型应该是这样的：
```
  class Appeal < ActiveRecord::Base
    belongs_to :appealer, :autosave => true
  end
```
接下来，按照您当前的逻辑，对于您的 appealer_params，将 appealer_params 方法更改为：
```
def appealer_params
  params.require(:appealer).permit(:first_name, :last_name)
end
```

为您的方案创建操作逻辑：

def create
  @appeal = Appeal.new(appeal_params)
  if appealer_params.present?
    appealer = Appealer.create(appealer_params)      
    @appeal.appealer = appealer
  end

  if @appeal.save
    respond_with @appeal
  else
    respond_with {:error}
  end
end

Rails 4 - belong_to 嵌套对象字段未保存

Rails 4 - belong_to nested object fields are not saved

ruby-on-rails

ruby-on-rails-4

nested-attributes

strong-parameters

belongs-to