trjhtr

Adding the items to the cart is very crucial. I have a session based shopping cart and I need to adjust that shopping cart along with the model because I will need the cart data or cart items in the database either.

Here is the models for the cart

class Cart(models.Model):
 user = models.ForeignKey(settings.AUTH_USER_MODEL, null=True, blank=True, on_delete=models.CASCADE)
 items = models.ManyToManyField(Variation, through='CartItem')
 quantity = models.PositiveIntegerField(default=1)
 timestamp = models.DateTimeField(auto_now_add=True, auto_now=False)
 updated = models.DateTimeField(auto_now_add=False, auto_now=True)
 subtotal = models.DecimalField(max_digits=50, decimal_places=2, default=0.00)
 tax_percentage = models.DecimalField(max_digits=10, decimal_places=5, default=0.085)
 tax_total = models.DecimalField(max_digits=50, decimal_places=2, default=0.00)
 total = models.DecimalField(max_digits=50, decimal_places=2, default=0.00)


class CartItem(models.Model):
 cart = models.ForeignKey(Cart, on_delete=models.CASCADE)
 item = models.ForeignKey(Variation, on_delete=models.CASCADE)
 quantity = models.PositiveIntegerField(default=1)
 line_item_total = models.DecimalField(max_digits=10, decimal_places=2)

carts.py

CART_ID = 'cart-id'


class Cart(Object):

 def __init__(self, request):
 """
 Initialize the cart
 """
 self.session = request.session
 # get the current session from request.session.get(CART_ID)
 cart = self.session.get(CART_ID)
 if not cart: # cart is not present in the session
 # save an empty cart in the session
 # but we expect our cart dictionary to use product ids as keys
 # and a dictionary with quantity and price as value for each key
 # by that we can gurantee same product is not added twice
 cart = self.session[CART_ID] = 
 else:
 try:
 cart = models.Cart.objects.get(id=cart)
 except models.Cart.DoesNotExist:
 cart = self.session[CART_ID] = 
 self.cart = cart


 def __iter__(self):
 """
 Iterate over the items in the cart and get the products from the database
 """
 product_ids = self.cart.keys()
 # get the product objects and add them to the cart
 products = models.Variation.objects.filter(id__in=product_ids)
 for product in products:
 self.cart[str(product.id)]['product'] = product
 for item in self.cart.values():
 item['price'] = Decimal(item['price'])
 item['total_price'] = item['price'] * item['quantity']
 yield item


 def __len__(self):
 """
 Count all the items in the cart
 """
 return sum(item['quantity'] for item in self.cart.values())


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


 def clear(self):
 # empty cart
 self.session[CART_ID] = 
 self.session.modified = True


 def new(self, request):
 cart = models.Cart(timestamp=datetime.datetime.now())
 cart.save()
 request.session[CART_ID] = cart.id
 return cart


 def add(self, product, quantity=1, update_quantity=False):
 """
 Add a product to the cart or update its quantity for True
 or the new quantity needs to be added to the existing quantity
 if it is False. We use the product id as a key and convert it to string
 because django uses JSON to serialize session data.
 """
 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):
 # update the session cart
 self.session[CART_ID] = self.cart
 # mark the session as modified to make sure it is saved
 self.session.modified = True


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

with the models i have, how do i refactor the above code to adjust with the models i have now so i will have track of the cart in the databases?