从控制器重构为模型

Question

我的订单控制器中有此操作：

# POST /orders
# POST /orders.json
def create
  @order = Order.new(params[:order])

  #spostare il ciclo cart > line_items come metodo del modello Order
  cart = session[:cart]

  cart.each do | id, quantity |
    item = Project.find_by_id(id)
    @line_item = LineItem.new
    @line_item.project = item
    @line_item.quantity = quantity
    @line_item.price = item.price
    @order.line_items << @line_item
  end

  @order.user = current_user

  session.delete(:cart)

  respond_to do |format|
    if @order.save
      #Send an email to admin
      UserMailer.order_created_to_admin(@order).deliver

      format.html { redirect_to :dashboard, notice: "L'ordine è stato creato correttamente." }
      format.json { render json: @order, status: :created, location: @order }
    else
      format.html { render action: "new" }
      format.json { render json: @order.errors, status: :unprocessable_entity }
    end
  end
end

现在我想对其进行一些重构，我正在考虑将以下几行作为方法移至 Order Model：

  cart.each do | id, quantity |
    item = Project.find_by_id(id)
    @line_item = LineItem.new
    @line_item.project = item
    @line_item.quantity = quantity
    @line_item.price = item.price
    @order.line_items << @line_item
  end

这样：

class Order < ActiveRecord::Base
  attr_accessible :user_id

  belongs_to :user
  has_many :line_items, :dependent => :destroy
  accepts_nested_attributes_for :line_items, :allow_destroy => true

  def add_line_items_to_order_from_cart(cart) do
    cart.each do | id, quantity |
      item = Project.find_by_id(id)
      @line_item = LineItem.new
      @line_item.project = item
      @line_item.quantity = quantity
      @line_item.price = item.price
      line_items << @line_item
    end
  end
end

并从控制器调用它，例如：

order.add_line_items_to_order_from_cart(cart)

就“瘦控制器/胖模型”模式而言是否有意义？

谢谢

编辑

我的订单模型现在：

class Order < ActiveRecord::Base
  attr_accessible :user_id

  belongs_to :user
  has_many :line_items, :dependent => :destroy
  accepts_nested_attributes_for :line_items, :allow_destroy => true
  validates :user, :presence => :true

  def add_line_items_to_order_from_cart(cart)
    cart.each do | id, quantity |
      item = Project.find(id)
      line_items << LineItem.new(project: item,
                                 quantity: quantity,
                                 price: item.price)
    end
  end

end

Answer 1

对我来说很有意义，您正在为模型提供哈希，而模型负责解析哈希并将其转换为数据库记录。

甚至可以将整个 line_item 内容移到一行中，这样更简洁：

def add_line_items_to_order_from_cart(cart) do
  cart.each do |id, quantity|
    item = Project.find_by_id(id)
    line_items << LineItem.new( project: item,
                                quantity: quantity,
                                price: item.price )
  end
end

你甚至可以这样尝试：

def add_line_items_to_order_from_cart(cart) do
  line_items = cart.map do |id, quantity|
    item = Project.find_by_id(id)
    LineItem.new( project: item,
                  quantity: quantity,
                  price: item.price )
  end
end

但总体思路是正确的，将这些东西移到模型中！ ;)