def add_to_cart(self, product, quantity=1):
"""
Add a new product into the Shopping Cart.
If the product is already in the cart then
update the quantity.
If not then create a new CartItem and set
appropriate value for its variable and save.
This method does nothing when 'quantity' < 1
"""
added = False
if quantity >= 0:
if CartService.contains_item(self.id, product.id):
print("Product Already in Cart")
# ci = CartItem.objects.get(product=product)
# ci = CartItem.objects.get(cart=self, product=product)
ci = self.cartitem_set.get(product=product)
added = self.update_quantity(ci.id, quantity)
# check if this product is already in the cart.
# if yes, then check if 'quantity' is not greater than
# that we have in stock.
# if it is lower then update the quantity in stock
else:
# create and save a new cart item
if (quantity <= (product.quantity - product.sell_quantity)):
item = CartItem()
item.set_product(product)
# this might throw an exception
item.set_quantity(quantity)
item.set_cart(self)
item.save()
added = True
return added
def contain_item(self, item_id):
"""
Deprecated : this method is slow on query.
Use the CartService.contains_items() from
cart.cart_service instead
"""
"""
flag = False
try:
start_time = datetime.datetime.now()
prod = Product.objects.get(pk=int(item_id))
item = self.cartitem_set.get(product=prod)
if item is not None:
flag = True
end_time = datetime.datetime.now()
elapsed_time = end_time - start_time
print("Cart : contain_item() processing time : {0} ms".format(elapsed_time.microseconds / 1000))
except ObjectDoesNotExist as e:
flag = False
"""
return CartService.contains_item(self.id, item_id)
def update_cart(self, item_id, quantity):
"""
item_id : ID of the Product to be updated
quantity: new quantity of the item .
precondition : quantity >= 0;
update_cart() updates the quantity value of a CartItem.
If quantity == 0 then that item will be removed from the cart.
if quantity < 0 this method returns false.
On success this method returns True.
Update :11.03.2018 : this method returns an object which
contains more infos on the result.
"""
response = {}
if (quantity >= 0):
if (CartService.contains_item(self.id, item_id)):
prod = Product.objects.get(pk=int(item_id))
item = self.cartitem_set.get(product=prod)
# item = self.get_item(item_id)
# item_quantity = item.get_quantity()
if quantity > 0:
in_stock = prod.quantity - prod.sell_quantity
if (quantity <= in_stock):
item.set_quantity(quantity)
item.save()
response['updated'] = True
response['quantity'] = quantity
else:
response['updated'] = False
response['quantity_error'] = True
response['quantity'] = item.quantity
else:
response['updated'] = self.remove_from_cart(item.id)
response['quantity'] = 0
return response