Django getting ForeignKey objects in APIView - django

Question

Hey so I am new to Django and I am writing a REST API with the following model .
# models.py
class Order(models.Model):
order_name = models.CharField(max_length=10, unique=True, default="")
def __str__(self):
return '{0}'.format(self.order_name).
class LineItem(models.Model):
order = models.ForeignKey(Order, on_delete=models.SET_NULL, null=True)
product = models.ForeignKey(Product, on_delete=models.SET_NULL, null=True)
class Meta:
unique_together = ('order', 'product')
def __str__(self):
return '{} - {}'.format(self.order.order_name, self.product.product_name).
# views.py
class OrderList(APIView):
def get(self, request):
orderlist = Order.objects.all()
serializer = OrderSerializer(orderlist, many=True)
return Response(serializer.data)
def post(self, request):
serializer = OrderSerializer(data=request.data)
if serializer.is_valid():
serializer.save()
return Response(serializer.data, status=status.HTTP_201_CREATED)
return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
class OrderDetail(APIView):
def get_object(self, order):
try:
return Order.objects.get(order_name=order_name)
except Order.DoesNotExist:
raise Http404
def get(self, request, order_name):
snippet = Order.objects.get(order_name=order_name)
snippet = snippet.lineitem_set.all()
serializer = OrderSerializer(snippet)
return Response(serializer.data)
So I am trying to code the OrderDetail(APIView)'s get method so that at /api/order/OrderA/ I get JSON with all the lineitems in that order. I've been struggling for a while with this now. Any suggestions?
class OrderSerializer(serializers.ModelSerializer):
class Meta:
model = Order
fields = ['order_name']

Answer 1

Change your serializer as below,
class LineItemSerializer(serializers.ModelSerializer):
class Meta:
model = LineItem
fields = ('id', 'product')
depth = 1
class OrderSerializer(serializers.ModelSerializer):
line_items = LineItemSerializer(many=True, source='lineitem_set')
class Meta:
model = Order
fields = ['order_name', 'line_items']
and then in your OrderDetail view as
class OrderDetail(APIView):
# your code
def get(self, request, order_name):
snippet = Order.objects.get(order_name=order_name)
serializer = OrderSerializer(snippet)
return Response(serializer.data)

Answer 2

DRF gives you a class to get the details of an object. Have a look here: http://www.django-rest-framework.org/api-guide/generic-views/#retrieveapiview
This an example code that should work if the order_name is passed as param in the url using a GET method.
from django.views.decorators.cache import never_cache
from django.utils.decorators import method_decorator
from rest_framework.exceptions import NotFound
from rest_framework.generics import RetrieveAPIView
# the decorator avoid to cache the object, maybe you don't need that.
#method_decorator(never_cache, name="dispatch")
class OrderDetail(RetrieveAPIView):
serializer_class = OrderSerializer
def get_object(self):
try:
return Order.objects.get(order_name=self.kwargs.get('order_name'))
except Order.DoesNotExist:
raise NotFound()