Django 过滤器找不到正确的解决方案

Question

my models:

class Order(models.Model):
id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name="order_user")
first_name = models.CharField(_('first name'), max_length=50)
last_name = models.CharField(_('last name'), max_length=50)
email = models.EmailField(_('e-mail'))
address = models.CharField(_('address'), max_length=250)
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
class OrderItem(models.Model):
id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
order = models.ForeignKey(Order, related_name='items', on_delete=models.CASCADE)
product = models.ForeignKey(Product, related_name='order_items', on_delete=models.CASCADE)
shop = models.ForeignKey(MyShop, related_name='shop_order', on_delete=models.CASCADE)
price = models.DecimalField(max_digits=10, decimal_places=2)
quantity = models.PositiveIntegerField(default=1)

我的观点:

def shop_orders(request):
order = Order.objects.filter(items__shop=request.user.user_profile_shop)
return render(request, 'account/paneli/shop/orders/shop_orders.html', {'order': order,})

在模板中，它显示了商店的订单但是它显示了所有商店的OrderItem

{% for order in order  %}
order.id #it ok  
{% for item in order.items.all %}

{{ item.product }}# wrong shows the OrderItem of all the shops

{% endfor %}
{% endfor %}

我哪里出错了，你能告诉我吗?

订单中有很多商店的产品，我想只过滤当前商店的产品

Answer 1

您可以使用prefetch_related和Prefetch()对象来过滤相关对象(加上通过解决N + 1问题使其更有效):

from django.db.models import Prefetch

def shop_orders(request):
orders = Order.objects.prefetch_related(
Prefetch(
'items',
queryset=OrderItem.objects.filter(shop=request.user.user_profile_shop).select_related('shop'),
to_attr='items_from_specific_shop'
)
)
return render(request, 'account/paneli/shop/orders/shop_orders.html', {'orders': orders,})

然后你可以在模板中写:

{% for order in orders %}
order.id
{% for item in order.items_from_specific_shop %}      
{{ item.product }}
{% endfor %}
{% endfor %}

Answer 2

在order_item的商店字段中使用相关名称进行用户反向查询

def shop_orders(request):
order = Order.objects.filter(items__shop=request.user.user_profile_shop)
shop = current_shop#get a shop whose items you need

order_for_shop = shop.shop_order.all()
return render(request, 'account/paneli/shop/orders/shop_orders.html', {'order': order_for_shop,})