ruby-on-rails – 如何限制current_user在每个时间段内向订单添

我正在Rails中建立一个具有特定销售模型的商店.我需要允许用户每30天只向其订单添加3个项目. 30天计数器应该在添加第一个order_item时开始.一旦30天到期,用户将能够添加3个订单.如果30天没有通过,例如,用户添加了两个ord??er_items,他仍然可以在30天内再添加一个order_item.
因此,如果用户尝试添加超过3个项目以显示错误消息,并忽略将order_items保存到current_user的订单.

我有产品,订单,order_items,用户.我想我应该向用户模型添加一些内容,但我不确定是什么.

order_items_controller.rb

def create
    @order = current_order
    @order_item = @order.order_items.new(order_item_params)
    @order.user_id = current_user.id
    @order.save
    session[:order_id] = @order.id

  respond_to do |format|
    format.js { flash[:notice] = "ORDER HAS BEEN CREATED." } 
  end
  end
private
  def order_item_params
    params.require(:order_item).permit(:quantity,:product_id,:user_id)
  end
end

user.rb

class User < ActiveRecord::Base
  has_many :identities,dependent: :destroy
  has_many :order
  # Include default devise modules. Others available are:
  # :confirmable,:lockable,:timeoutable and :omniauthable
  devise :omniauthable,:invitable,:database_authenticatable,:registerable,:recoverable,:rememberable,:trackable
end

order_item.rb

class OrderItem < ActiveRecord::Base
  belongs_to :product
  belongs_to :order

  validates :quantity,presence: true,numericality: { only_integer: true,greater_than: 0 }
  validate :product_present
  validate :order_present

  before_save :finalize

  def unit_price
    if persisted?
      self[:unit_price]
    else
      product.price
    end
  end

  def total_price
    unit_price * quantity
  end

private
  def product_present
    if product.nil?
      errors.add(:product,"is not valid or is not active.")
    end
  end

  def order_present
    if order.nil?
      errors.add(:order,"is not a valid order.")
    end
  end

  def finalize
    self[:unit_price] = unit_price
    self[:total_price] = quantity * self[:unit_price]
  end
end

order.rb

class Order < ActiveRecord::Base
  belongs_to :order_status
  has_many :order_items
  before_create :set_order_status
  before_save :update_subtotal

  def subtotal
    order_items.collect { |oi| oi.valid? ? (oi.quantity * oi.unit_price) : 0 }.sum
  end
private
  def set_order_status
    self.order_status_id = 1
  end

  def update_subtotal
    self[:subtotal] = subtotal
  end
end

carts_controller.rb

class CartsController < ApplicationController
  def show
    @order_items = current_order.order_items
  end

的routes.rb

resources :order_items,only: [:create,:update,:destroy,:new]

form.html.erb

<%= form_for OrderItem.new,html: {class: "add-to-cart"},remote: true do |f| %>


        <div class="input-group">
          <%= f.hidden_field :quantity,value: 1,min: 1 %>
          <div class="input-group-btn">
            <%= f.hidden_field :product_id,value: product.id %>
            <%= f.submit "Add to Cart",data: { confirm: 'Are you sure that you want to order this item for current month?'},class: "btn btn-default black-background white" %>
          </div>
        </div>
      <% end %>
    </div>

rails generate migration AddOrderCounterToUser

class AddPartNumberToProducts < ActiveRecord::Migration
  def change
    add_column :users,:begin_date,:date
    add_column :users,:order_counter,:integer 
  end
end

def create
  now = Date.today
  success = false
  if current_user.begin_date && ((now - 30) < current_user.begin_date)
     if current_user.order_counter >= 3
        # deal with the case that order should not be created,# for example redirect.
     else
       current_user.order_counter += 1
       current_user.save
       success = true
     end
  else 
    current_user.order_counter = 1
    current_user.begin_date = now
    current_user.save
    success = true
  end
  if success
    @order = current_order
    @order_item = @order.order_items.new(order_item_params)
    @order.user_id = current_user.id
    @order.save
    session[:order_id] = @order.id

    respond_to do |format|
      format.js { flash[:notice] = "ORDER HAS BEEN CREATED." } 
    end
  else 
    respond_to do |format|
      format.js { flash[:notice] = "CREATION NOT POSSIBLE." } 
    end
  end
end