Django Cart - 产品的多种配置选项

Question

我想创建一个Django Web应用程序，用户可以在其中添加项目到购物车。

没有模型Colour和Size这到目前为止工作。

我的问题是，我无法弄清楚如何以正确的方式实现配置选项（例如）Colour和Size。

我添加了两个“选项”与多对一关系。我现在可以为产品添加多种颜色和尺寸，但不知道如何在CartEntry中保存选择的“选项”

这是我到目前为止所得到的：

from django.db import models
from django.contrib.auth.models import User

class Product(models.Model):
    name = models.CharField(max_length=256)
    price = models.DecimalField(max_digits=6, decimal_places=2)
    def __str__(self):
        return str(self.name)


class Colour(models.Model):
    product = models.ForeignKey(Product, on_delete=models.CASCADE, related_name="rel_colour")
    option = models.CharField(max_length=24)
    price = models.DecimalField(max_digits=6, decimal_places=2)
    def __str__(self):
        return str(self.colour)

class Size(models.Model):
    product =models.ForeignKey(Product, on_delete=models.CASCADE, related_name="rel_size")
    option = models.CharField(max_length=24)
    price = models.DecimalField(max_digits=6, decimal_places=2)
    def __str__(self):
        return str(self.size)



class Cart(models.Model):
    user        = models.ForeignKey(User, null=True, blank=True, on_delete=models.CASCADE)
    products    = models.ManyToManyField(Product, blank=True)
    updated     = models.DateTimeField(auto_now=True)
    timestamp   = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return str(self.id) + ' - ' + str(self.user)


class CartEntry(models.Model):
    product = models.ForeignKey(Product, null=True, on_delete=models.CASCADE)
    cart = models.ForeignKey(Cart, null=True, on_delete=models.CASCADE)
    quantity = models.PositiveIntegerField()

    def __str__(self):
        return str(self.quantity) + ', ' + str(self.product.name)

也许我不能在这里为CartEntry用户关系？

Answer 1

为什么不这样做：

    from django.db import models
    from django.contrib.auth.models import User

    class Product(models.Model):
        name = models.CharField(max_length=256)
        colour = models.ForeignKey(Colour, on_delete=models.CASCADE)
        size = models.ForeignKey(Size, on_delete=models.CASCADE)
        price = models.DecimalField(max_digits=6, decimal_places=2)
        def __str__(self):
            return str(self.name)

    class Colour(models.Model):
        name = models.CharField(max_length=24)
        def __str__(self):
            return str(self.name)

    class Size(models.Model):
        name = models.CharField(max_length=24)
        def __str__(self):
            return str(self.name)

所以每种产品都有不同的颜色和大小。或者如果你想把一个产品作为“父”，你可以添加另外一个模型，比如说VariantProduct

    class Product(models.Model):
        name = models.CharField(max_length=256)
        def __str__(self):
            return str(self.name)

    class VariantProduct(models.Model):
        product = models.ForeignKey(Product, on_delete=models.CASCADE)
        name = models.CharField(max_length=256)
        colour = models.ForeignKey(Colour, on_delete=models.CASCADE)
        size = models.ForeignKey(Size, on_delete=models.CASCADE)
        price = models.DecimalField(max_digits=6, decimal_places=2)
        def __str__(self):
            return str(self.name)