How to design a Django API to handle a "Dynamic" form? - django

Question

I have built an Angular form that contains a form array. So the user has the control to add fields or delete fields from the form. What I am trying to understand is how I can design a Django API that can handle the post for this kind of dynamic form?
I do not want the user to create an account on the website in order to place his order. Is that even possible?

Answer 1

You should be more concerned about how to model your data, than you can think about your interface. Here a few options for modeling your data:
Option One is to use regular Django ORM, and in this case you may use the JSONField for any dynamic properties.
Option two is to use any schemaless data model, such as document-based databases(e.g MongoDB).
Here a simple example, on how to use Django's JSONField:
your model:
class Order(models.Model):
customer = models.ForeignKey(User, on_delete=models.CASCADE)
#any additional static fields
properties = JSONField()
your view:
def create_order_view(request):
if request.method == "POST":
#do your validation
Order.objects.create(user=request.user, properties=request.POST["properties"])
return Response(status=200)
this example is totally incomplete as you have to add validation error handling, and it is a better idea to use Django rest-framework for constructing your API.
Finally as I said there many option to model your data, in addition to what I mentioned above there are many other. To decide what model to use, you have to know how your data gonna be consumed, so you can optimze for query time, in addition there are many other factors but this is out of scope of this asnwer.

Answer 2

For me, I used Django-RESTframework to build the api.
The way to achieve this is simple, just create the model and iterate through the items which is the dynamic part, and assign the Foreignkey field to obj.id created. First, I created the main model instance, then created the instances of the child instances. I will use Order and Item to demonstrate the idea, The Item instance will have Foreinkey field to Order model.
In the Item model, add "related_name" argument to the Foreinkey field
order = models.ForeignKey(Order, related_name='items',on_delete=models.CASCADE)
serializers.py
class ItemSerializer(serializers.ModelSerializer):
class Meta:
model = Item
fields = [
....your fields...
]
class OrderSerializer(serializers.ModelSerializer):
items = ItemSerializer(many=True)
class Meta:
model = Order
fields = [
'order', ....
]
def create(self, validated_data):
items_data = validated_data.pop("items")
order = Order.objects.create(**validated_data)
order.total_fees = order.delivery_fees
for item in items_data:
i = Item.objects.create(order=order, **item)
return order