當我嘗試以用戶身份登錄時在mixin中出現錯誤

Question

我創建了一個訂單頁面，客戶可以查看他在過去完成的所有訂單，但由於我希望客戶登錄並查看訂單，所以我創建了一個loginrequiredmixin

mixins.py

from django.contrib.auth.decorators import login_required 
from django.utils.decorators import method_decorator 

from carts.models import Cart 
from .models import Order 


class LoginRequiredMixin(object): 
    @method_decorator(login_required) 
    def dispatch(self, request, *args, **kwargs): 
     return super(LoginRequiredMixin, self).dispatch(request,*args, **kwargs) 



class CartOrderMixin(object): 
    def get_order(self, *args, **kwargs): 
     cart = self.get_cart() 
     if cart is None: 
      return None 
     new_order_id = self.request.session.get("order_id") 
     if new_order_id is None: 
      new_order = Order.objects.create(cart=cart) 
      self.request.session["order_id"] = new_order.id 
     else: 
      new_order = Order.objects.get(id=new_order_id) 
     return new_order 

    def get_cart(self, *args, **kwargs): 
     cart_id = self.request.session.get("cart_id") 
     if cart_id == None: 
      return None 
     cart = Cart.objects.get(id=cart_id) 
     if cart.items.count() <= 0: 
      return None 
     return cart 

views.py

from django.shortcuts import render 
from django.views.generic.edit import CreateView, FormView 
from django.views.generic.list import ListView 
# Create your views here. 
from .mixins import CartOrderMixin, LoginRequiredMixin 
from .models import UserCheckout, Order 

class OrderList(LoginRequiredMixin, ListView): 
    queryset = Order.objects.all() 

    def get_queryset(self): 
     user_check_id = self.request.user.id 
     user_checkout = UserCheckout.objects.get(id=user_check_id) 
     return super(OrderList, self).get_queryset().filter(user=user_checkout) 

models.py

from decimal import Decimal 
from django.conf import settings 
from django.db import models 
from django.db.models.signals import pre_save 

# Create your models here. 
from carts.models import Cart 


class UserCheckout(models.Model): 
    user = models.OneToOneField(settings.AUTH_USER_MODEL, null=True, blank=True) #not required 
    email = models.EmailField(unique=True) #--> required 


    def __unicode__(self): #def __str__(self): 
     return self.email 

ORDER_STATUS_CHOICES = (
     ('created', 'Created'), 
     ('completed', 'Completed') 
    )  

class Order(models.Model): 
    status = models.CharField(max_length=120, choices=ORDER_STATUS_CHOICES, default ='created') 
    cart = models.ForeignKey(Cart) 
    user = models.ForeignKey(UserCheckout, null=True) 
    #shipping_address = models.ForeignKey 
    #final_total_price = models.DecimalField(default=) 
    order_total = models.DecimalField(max_digits=50, decimal_places=2,) 
    #orderid 
    def __unicode__(self): 
     return str(self.cart.id) 

    def mark_completed(self): 
     self.status = "completed" 
     self.save()  

def order_pre_save(sender, instance, *args, **kwargs): 
    cart_total = instance.cart.total 
    order_total = Decimal(cart_total) 
    instance.order_total = order_total 

pre_save.connect(order_pre_save, sender=Order) 

錯誤

DoesNotExist at /orders/ 
UserCheckout matching query does not exist. 
Request Method: GET 
Request URL: http://127.0.0.1:8000/orders/ 
Django Version: 1.8.4 
Exception Type: DoesNotExist 
Exception Value:  
UserCheckout matching query does not exist. 
Exception Location: /Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/site-packages/django/db/models/query.py in get, line 334 
Python Executable: /Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/bin/python 
Python Version: 2.7.10 
Python Path:  
['/Users/apulgupta/Documents/ecommerce-2-before-guest-save/Try-Django-1.8/src', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python27.zip', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/plat-darwin', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/plat-mac', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/plat-mac/lib-scriptpackages', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/lib-tk', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/lib-old', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/lib-dynload', 
'/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7', 
'/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-darwin', 
'/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk', 
'/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac', 
'/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/plat-mac/lib-scriptpackages', 
'/Users/apulgupta/Desktop/ecommerce-2/Try-Django-1.8/lib/python2.7/site-packages'] 
Server time: Wed, 15 Mar 2017 17:42:22 +0000 

只要我得到的登錄頁面，我嘗試登錄我得到上述錯誤

Answer 1

這是因爲UserCheckout.objects.get(id=user_check_id)失敗。

你應該抓住任何可能的失敗是這樣的：

try: 
    user_checkout = UserCheckout.objects.get(id=user_check_id) 
except UserCheckout.DoesNotExist as e: 
    # do something if UserCheckout obj with user_check_id does not exist 
else: 
    # user_checkout succeeded. Procceed 

，或者如果對象不存在

from django.shortcuts improt get_object_or_404 

def get_queryset(self): 
    user_check_id = self.request.user.id 
    user_checkout = get_object_or_404(UserCheckout, id=user_check_id) 
    return super(OrderList, self).get_queryset().filter(user=user_checkout) 

Answer 2

我寧願說，這更多的是一個合乎邏輯的，你可以拋出一個404頁錯誤我的壞：|

在上面的代碼中，我試圖比較兩個量，即導致該錯誤的用戶的用戶名和電子郵件地址ID。所以我決定通過使用用戶名和電子郵件地址作爲一個整體，然後比較它這爲我工作

編輯來讓事情變得更簡單 views.py

from django.shortcuts import render 
from django.views.generic.edit import CreateView, FormView 
from django.views.generic.list import ListView 
# Create your views here. 
from .mixins import CartOrderMixin, LoginRequiredMixin 
from .models import UserCheckout, Order 

class OrderList(LoginRequiredMixin, ListView): 
    queryset = Order.objects.all() 

    def get_queryset(self): 
     user_check_id = self.request.user.email 
     template_name = 'orders/order_list.html' 
     print user_check_id 
     user_checkout = UserCheckout.objects.get(email=user_check_id) 
     print user_checkout 
     return super(OrderList, self).get_queryset().filter(user=user_checkout)