Django - 坚持创建定价系统

Question

我正在制作一个“预订 airbnb”网站。

在我的公寓详细信息页面上，我有一个 JQuery UI Date Picker 日历，用户使用它来输入预订的开始日期和结束日期。

一旦完成并且用户提交了我想刷新整个网站的表单，刷新时会显示用户之前选择的日期，以及每天的价格和总价。

在我创建的模型中：

models.py：

class Apartment(models.Model):
    title = models.CharField(max_length=200)
    address = models.CharField(max_length=200)
    city = models.CharField(max_length=100)
    state = models.CharField(max_length=100)
    zipcode = models.CharField(max_length=20)
    description = models.TextField(blank=True)
    apartment_price = models.IntegerField()
    bedrooms = models.IntegerField()
    bathrooms = models.DecimalField(max_digits=2, decimal_places=1)
    garage = models.IntegerField(default=0)
    size = models.IntegerField()
    photo_main = models.ImageField(upload_to='photos/%Y/%m/%d/')
    list_date = models.DateTimeField(default=datetime.now, blank=True)

    def __str__(self):
        return self.title

class ApartmentImages(models.Model):
    apartment = models.ForeignKey(Apartment, on_delete="models.CASCADE", related_name="image")
    image = models.ImageField("image")

    def __str__(self):
        return self.image.url


class ApartmentPrices(models.Model):
    apartment = models.ForeignKey(Apartment, on_delete="models.CASCADE", related_name="price")
    price_start_date = models.DateField(blank=True, null=True)
    price_end_date = models.DateField(blank=True, null=True)
    price = models.IntegerField()

    def __str__(self):
        return self.apartment.title

class Reservation(models.Model):
    apartment = models.ForeignKey(Apartment, related_name='reservations',
                                  on_delete=models.CASCADE, blank=True, null=True)
    start_date = models.DateField(blank=True, null=True)
    end_date = models.DateField(blank=True, null=True)
    name = models.CharField(default="", max_length=200)

    def __str__(self):
        return self.name

这是我目前的看法。我尝试了很多不同的东西，但我一直坚持这应该如何工作的逻辑。

这是我的看法：

def apartment_view(request, apartment_id):

    reservation = Reservation.objects.filter(apartment__pk=apartment_id)
    apartment = get_object_or_404(Apartment, pk=apartment_id)
    prices = ApartmentPrices.objects.filter(apartment__pk=apartment_id)
    context = {}
    context['apartment'] = apartment
    context['prices'] = prices

    # svi datumi za cijene
    price_dates = []
    for start, end, price in prices.values_list('price_start_date', 'price_end_date', 'price'):
        while start <= end:
            price_dates.append(start.strftime('%-d-%m-%Y'))
            price_dates.append(price)
            start += datetime.timedelta(days=1)


    unavailable = []
    for start, end in apartment.reservations.values_list('start_date', 'end_date'):
        while start <= end:
            unavailable.append(start.strftime('%-d-%m-%Y'))
            start += datetime.timedelta(days=1)
    form = ReservationForm()
    context['unavailable_dates'] = json.dumps(unavailable)
    context['form'] = form

    if request.method == 'GET':
        form = ReservationForm()

    elif request.method == 'POST':
        form = ReservationForm(request.POST)
        if form.is_valid():
            reservation = form.save(commit=False)
            reservation.apartment = apartment
            reservation.save()
            form.save()
            return render(request, "booking/apartment.html", context)


    return render(request, 'booking/apartment.html', context)

那么谁能帮我弄清楚将用户选择的日期与数据库中的价格日期进行比较并获得价格的最佳方法是什么？

非常感谢，已经卡了一段时间了。

Answer 1

您可以为 Appartment 提供一个方法来获取给定日期对象在开始日期和结束日期之间的价格。 （未经测试）

...
from django.db.models import Q


class Apartment(models.Model):
    ...
    def price_by_date(self, date_obj):
        """returns the first price with date_obj is between start and end date

        Args:
            date_obj(datetime.date): the date of the price you want

        Returns:
            ApartmentPrices: first valid price found
        """
        # self.price is a back reference to all prices with self as apartment
        # you named it by giving related_name="price" in ApartmentPrices.apartment
        return self.price.filter(
            Q(price_start_date__lte=date_obj) & Q(price_end_date__gte=date_obj)
        ).first()
    ...

在视图中你应该可以做到：

...
def apartment_view(request, apartment_id):

    reservation = Reservation.objects.filter(apartment__pk=apartment_id)
    apartment = get_object_or_404(Apartment, pk=apartment_id)
    date_price = apartment.price_by_date(datetime.date(2019, 10,18))
    # date_price.price would be the integer
    ...

更多信息：

Q - queries 用于将两个查询（开始+结束）合并为一个查询。