Expecting JSON object instead of JSON Array - json

Question

In my django application with database engine djongo, I'm trying to return a JSON response by retrieving from my database. But, I'm receiving JSON array instead of JSON object. Currently, there is only one record in my database. Please see the code below.
model.py
class bloodDonors(models.Model):
location=models.CharField(max_length=20)
name=models.CharField(max_length=20)
phone=models.IntegerField()
address=models.TextField()
bloodGroup=models.CharField(max_length=5)
type=models.CharField(max_length=20)
def __str__(self):
return self.name
views.py
class bloodDonersView(viewsets.ModelViewSet):
queryset = bloodDonors.objects.all()
serializer_class = bloodDonorsSerializer
JSON Reponse:
[
{
"id": 3,
"location": "Delhi",
"name": "Tony",
"phone": 888,
"address": "South street",
"bloodGroup": "B+",
"type": "blood-donation"
}
]
But, actually I needed the response as given below:
{
"id": 3,
"location": "Delhi",
"name": "Tony",
"phone": 888,
"address": "South street",
"bloodGroup": "B+",
"type": "blood-donation"
}

Answer 1

It sounds like you are using the 'list' endpoint that retrieves all objects matching the queryset, but you want to be using the detail retrieve endpoint, where you just retrieve one object. The good news is that because you are using a Model viewset, you get a detail retrieve GET endpoint for free. All you have to do is pass in the pk of the object you want as part of the url and it will return only the single object you requested.
So if your url is currently:
/api/v1/blood-donors
you'd want to use the url:
/api/v1/blood-donors/3
to get just the single object you want (with pk=3). The GET endpoint with no /{PK} at the end is always going to return a list, even if there's only one object in your database, and if you add the pk to the url you will always only get one object back, the object that matches the pk you pass in.
Update to answer your question in the comment. The new method would look something like this:
class bloodDonersView(viewsets.ModelViewSet):
queryset = bloodDonors.objects.all()
serializer_class = bloodDonorsSerializer
#action(detail=False, methods=['get',], url_path='first')
def get_first_object(self, request):
object = bloodDonors.objects.first()
serializer = bloodDonorsSerializer(object, many=False)
return response.Response(serializer.data)
the url you would use is
api/v1/blood-donors/first
and you need to check the documentation about where to import response and the action decorator.