fixed 404 on cart page for newly registered user

[nicholas-davison]

Description of PR that completes issue here... When a new user registered themselves and navigated to the cart page, a 404 was being thrown because there was no order matching the user id. furthermore, there was a 500 being thrown due to the database expecting a date.today() instead of a datetime.now() when setting the date for a new order.

Changes

• Imported date from datetime in django
• removed unused 'as ex' variable
• replaced created_date value on new order with date.today()
• in list function of cart view, replaced content of exception statement that threw '404 not found' with functionality to add a new order, then moved subsequent serialization logic below that try/except block
• removed product list serializer and statement that added product list as property on the new order object, as it was unused

Requests / Responses

If this PR contains code that defines a new request/response, or changes an existing one, please put the JSON representations here.

Request

GET /cart gets current users cart

Response

HTTP/1.1 200 OK

{
    "id": 10,
    "url": "http://localhost:8000/orders/10",
    "created_date": "2018-11-03",
    "payment_type": null,
    "customer": "http://localhost:8000/customers/4",
    "lineitems": [],
    "size": 0
}

Testing

• [ ] Register new user in browser
• [ ] Navigate to cart
• [ ] An empty cart should be displayed with no error messages in window or console

Related Issues

• Fixes #55

[samsheps]

looks great, nick! 404 no more