python - 如何在Django中将2列求和get_context_data()

我想在ClassBasedView的get_context_data方法中将总值作为收益变量返回。

我还想返回另一个操作：total-shipping_cost作为上下文中的revenue_no_shipping_cost变量。

我试过了：

from django.db.models import F, Sum

class OrdersListView(PermissionRequiredMixin,ListView):

    model = Order
    permission_required = 'is_staff'
    template_name = "order/revenue.html"
    paginate_by = 10

    def get_queryset(self):
        filter_month = self.request.GET.get('filtromes', '0')
        if filter_month == "0":
            return Order.objects.filter(status = 'recibido_pagado')
        else:
            return (Order.objects
                .filter(created__month=filter_month, status = 'recibido_pagado'))

    def get_context_data(self, **kwargs):
        context = super(OrdersListView, self).get_context_data(**kwargs)
        qs = kwargs.pop('object_list', self.object_list)
        order = self.request.GET.get('orderby', 'created')
        context = {}
        revenue = qs.aggregate(revenue=Sum('total'))
        revenue_no_shipping = qs.annotate(revenue_no_shipping=F('total') + F('shipping_cost'))
        context['revenue'] = revenue
        context['revenue_no_shipping'] = revenue_no_shipping
        context['filtromes'] = self.request.GET.get('filtromes', '0')
        context['orderby'] = self.request.GET.get('orderby', 'created')
        context['category'] = "catalogo"
        return context

但是在模板中，我得到：

收入：{'revenue': Decimal('42')} #is 42.00
对于Revenue_no_shipping：<QuerySet [<Order: 58>]> #Should be 25.00

models.py：

class Order(models.Model):
    ORDER_STATUS = (
        ('recibido_pagado', 'Recibido y pagado'),
        ('recibido_no_pagado', 'Recibido pero no pagado'),
        ('en_proceso', 'En proceso'),
        ('en_camino', 'En camino'),
        ('entregado', 'Entregado'),
        ('cancelado', 'Cancelado por no pagar' )
    )
    token = models.CharField(max_length=100, blank=True, null=True)
    first_name = models.CharField(max_length=50, blank=True, null=True)
    last_name = models.CharField(max_length=50, blank=True, null=True)
    phone_number = models.CharField(max_length=30, blank=True)
    total = models.DecimalField(max_digits=10, decimal_places=2)
    stickers_price = models.DecimalField(max_digits=10, decimal_places=2)
    discount = models.DecimalField(max_digits=10, decimal_places=2, default=Decimal('0.00'))
    shipping_cost = models.DecimalField(max_digits=10, decimal_places=2)
    email = models.EmailField(max_length=250, blank = True, verbose_name= 'Correo electrónico')
    last_four = models.CharField(max_length=100, blank=True, null=True)
    created = models.DateTimeField(auto_now_add=True)
    shipping_address = models.CharField(max_length=100, blank=True, null=True)
    shipping_address1 = models.CharField(max_length=100, blank=True, null=True)
    reference = models.CharField(max_length=100, blank=True, null=True)
    shipping_department = models.CharField(max_length=100, blank=True, null=True)
    shipping_province = models.CharField(max_length=100, blank=True, null=True)
    shipping_district = models.CharField(max_length=100, blank=True, null=True)
    reason = models.CharField(max_length=400, blank=True, null=True, default='')
    status = models.CharField(max_length=20, choices=ORDER_STATUS, default='recibido_pagado')
    comments = models.CharField(max_length=400, blank=True, null=True, default='')
    cupon = models.ForeignKey('marketing.Cupons', blank=True, null=True, default=None, on_delete=models.SET_NULL)


    class Meta:
        db_table = 'Order'
        ordering = ['-created']

    def __str__(self):
        return str(self.id)

    def igv(self):
        igv = int(self.total) * 18/100
        return igv

    def shipping_date(self):
        shipping_date = self.created + datetime.timedelta(days=10)
        return shipping_date

    def deposit_payment_date(self):
        deposit_payment_date = self.created + datetime.timedelta(days=2)
        return deposit_payment_date

更新1：

模板中的HTML

<h1>Ordenes recibidas y pagadas:</h1>
<p> {{ revenue }}</p>

<h1>Ordenes recibidas y pgadas (no shipping)</h1>
<p> {{ revenue_no_shipping }}</p>

更新了get_context_data方法：

def get_context_data(self, **kwargs):
        context = super(OrdersListView, self).get_context_data(**kwargs)
        qs = kwargs.pop('object_list', self.object_list)
        order = self.request.GET.get('orderby', 'created')
        context = {}
        revenue = qs.aggregate(revenue=Sum('total'))
        revenue_no_shipping = qs.aggregate(revenue_no_shipping=Sum(F('total') + F('shipping_cost')))
        context['revenue'] = revenue
        context['revenue_no_shipping'] = revenue_no_shipping
        context['filtromes'] = self.request.GET.get('filtromes', '0')
        context['orderby'] = self.request.GET.get('orderby', 'created')
        context['category'] = "catalogo"
        return context

最后答案：

根据jmunsch的答案，我得到了正确的答案，只需添加：

 revenue = float(revenue['revenue']) #necessary to properly render in template / not as Decimal
        revenue_no_shipping = float(revenue_no_shipping['revenue_no_shipping']) #necessary to properly render in template / not as Decimal

在模板中正确呈现。

def get_context_data(self, **kwargs):
        context = super(OrdersListView, self).get_context_data(**kwargs)
        qs = kwargs.pop('object_list', self.object_list)
        order = self.request.GET.get('orderby', 'created')
        context = {}
        revenue = qs.aggregate(revenue=Sum('total'))
        revenue_no_shipping = qs.aggregate(revenue_no_shipping=Sum(F('total') - F('shipping_cost')))
        revenue = float(revenue['revenue']) #necessary to properly render in template / not as Decimal
        revenue_no_shipping = float(revenue_no_shipping['revenue_no_shipping']) #necessary to properly render in template / not as Decimal
        context['revenue'] = revenue
        context['revenue_no_shipping'] = revenue_no_shipping
        context['filtromes'] = self.request.GET.get('filtromes', '0')
        context['orderby'] = self.request.GET.get('orderby', 'created')
        context['category'] = "catalogo"
        return context

最佳答案

对于使用django求和两列的方法，这样的事情可能起作用：

qs.aggregate(revenue_no_shipping=Sum(F('total') - F('shipping_cost')))