我有一个订单表，它有一个item_details键，我想让item_details的值是一个对象数组？我该怎么做？这是我目前所拥有的。请求被成功发布，但它看起来像这样？我该怎么修复它？
订单管理员

class OrdersController < ApplicationController

    skip_before_action :authorized, only: :create

    def index
        orders = Order.all
        if orders
        render json: orders
        else
            render json: {error: "Order Not Found" }, status: :not_found
        end
    end

    def show
        order = Order.find_by(id: params[:id])
        if order
            render json: order
        else
            render json: { error: "Order Not Found" }, status: :not_found
        end
    end

    def create
        order = Order.create(order_params)
        render json: order, status: :created
    end

    def update
        order = Order.find_by(id: params[:id])
        if order
            order.update(order_params)
            render json: order
        else
            render json: { error: "Order Not Found" }, status: :not_found
        end
    end

    private

    def order_params
        params.permit(:customer_id, :order_date,{ item_details: [:product_id, :quantity] })
    end

end

订单序列化程序

class OrderSerializer < ActiveModel::Serializer
  attributes :id, :customer_id, :order_date, :total_cost, :item_details

  belongs_to :customer
  has_many :order_details
  has_many :products

  def total_cost
    cost = []
    self.object.order_details.each do |details|
      product = self.object.products.find {|product| product.id == details.product_id}
      cost << product.price * details.quantity
    end
    return cost.sum
  end

end

图式

create_table "orders", force: :cascade do |t|
    t.integer "customer_id"
    t.string "order_date"
    t.datetime "created_at", precision: 6, null: false
    t.datetime "updated_at", precision: 6, null: false
    t.text "item_details", default: [], array: true
  end

发布人员请求

{
    "customer_id": 1,
    "order_date": 1,
    "item_details": [
        {
            "product_id": 1,
            "quantity" : 2
        },
        {
            "product_id": 7,
            "quantity" : 1
        }
    ]
}

Postman 返回

{
    "id": 2,
    "customer_id": 1,
    "order_date": "1",
    "total_cost": 0,
    "item_details": [
        "{\"product_id\"=>1, \"quantity\"=>2}",
        "{\"product_id\"=>7, \"quantity\"=>1}"
    ],
    "customer": {
        "id": 1,
        "name": "John Smith",
        "phone_number": "(811) 833 2172",
        "email": "john@yahoo.com",
        "address": "334 Jacobs Plaza, West Robtport, IN 26209-0933",
        "username": "john103",
        "password": null
    },
    "order_details": [],
    "products": []
}

我不知道为什么has看起来像这样“{“product_id”=〉1，“quantity”=〉2}”它是一个字符串而不是一个实际的对象？