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Question

Django

I'm making a cart for IM, when I add a product, it should redirect to the cart page, but for some reason it returns a 404 error.
The console says Not Found: /cart/
Cart

#views.py
@require_POST
def cart_add(request, product_id):
    cart = Cart(request)
    product = get_object_or_404(Product, id=product_id)
    form = CartAddProductForm(request.POST)
    if form.is_valid():
        cd = form.cleaned_data
        cart.add(product=product,
                 quantity=cd['quantity'],
                 update_quantity=cd['update'])
    return redirect('cart:cart_detail')

def cart_remove(request, product_id):
    cart = Cart(request)
    product = get_object_or_404(Product, id=product_id)
    cart.remove(product)
    return redirect('cart:cart_detail')

def cart_detail(request):
    cart = Cart(request)
    return render(request, 'cart/detail.html', {'cart': cart})

#cart.py
class Cart(object):
    def __init__(self, request):
        self.session = request.session
        cart = self.session.get(settings.CART_SESSION_ID)
        if not cart:
            # save an empty cart in the session
            cart = self.session[settings.CART_SESSION_ID] = {}
        self.cart = cart
        # store current applied coupon
        self.coupon_id = self.session.get('coupon_id')

    def __iter__(self):
        product_ids = self.cart.keys()
        # get the product objects and add them to the cart
        products = Product.objects.filter(id__in=product_ids)

        cart = self.cart.copy()
        for product in products:
            cart[str(product.id)]['product'] = product

        for item in cart.values():
            item['price'] = Decimal(item['price'])
            item['total_price'] = item['price'] * item['quantity']
            yield item

    def __len__(self):
        return sum(item['quantity'] for item in self.cart.values())

    def add(self, product, quantity=1, update_quantity=False):
        product_id = str(product.id)
        if product_id not in self.cart:
            self.cart[product_id] = {'quantity': 0,
                                      'price': str(product.price)}
        if update_quantity:
            self.cart[product_id]['quantity'] = quantity
        else:
            self.cart[product_id]['quantity'] += quantity
        self.save()

    def save(self):
        # mark the session as "modified" to make sure it gets saved
        self.session.modified = True

    def remove(self, product):
        product_id = str(product.id)
        if product_id in self.cart:
            del self.cart[product_id]
            self.save()

    def get_total_price(self):
        return sum(Decimal(item['price']) * item['quantity'] for item in self.cart.values())

    def clear(self):
        # remove cart from session
        del self.session[settings.CART_SESSION_ID]
        self.save()

#urls.py
app_name = 'cart'
urlpatterns = [
    path('', views.cart_detail, name='cart_detail'),
    path('add/<int:product_id>/', views.cart_add, name='cart_add'),
    path('remove/<int:product_id>/', views.cart_remove, name='cart_remove'),
]

#forms.py
PRODUCT_QUANTITY_CHOICES = [(i, str(i)) for i in range(1, 21)]

class CartAddProductForm(forms.Form):
    quantity = forms.TypedChoiceField(
                                    choices=PRODUCT_QUANTITY_CHOICES,
                                    coerce=int)
    update = forms.BooleanField(required=False,
                                initial=False,
                                widget=forms.HiddenInput)

shop

#views.py
def product_detail(request, id, slug):
    product = get_object_or_404(Product, id=id, slug=slug, available=True)
    cart_product_form = CartAddProductForm()
    return render(request, 'shop/product/detail.html', {'product': product,
                                                        'cart_product_form': cart_product_form})

#detail.html
<form action="{% url 'cart:cart_add' product.id %}" method="post">
  {{ cart_product_form }}
  {% csrf_token %}
  <input type="submit" value="Add to cart">
</form>

Answer 1

Maybe it's the missing '/': but that's not certain