Django Rest Framework Returning a single value

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If i had a model as below, how would i return the total number of miles in the DB? If i use the aggregate function then it will work, but it will iterate through all objects and give me the total next to those objects.

models.py

from django.db import models

class Rec(models.Model):
    name = models.CharField(max_length=50)
    miles = models.IntegerField()

serializers.py

class SummarySerializer(serializers.Serializer):
    total_miles = serializers.SerializerMethodField()

    def get_total_miles(self, obj):
        return Rec.objects.filter(name=obj.name).aggregate(Sum('miles'))

views.py

class SummaryViewSet(viewsets.ModelViewSet):
    serializer_class = SummarySerializer
    queryset = Rec.objects.all()

current output

[{'total':1000, 'total':1000, 'total':1000.... etc}]

Desired output (one instance of the value)

[{'total_miles': 1000}]
django-rest-framework aggregate serialization
1 Answers

Django aggregate returns a dict(), When you aggregate data you should add a key to it and then spit the key

 def get_total_miles(self, obj):
        return Rec.objects.filter(name=obj.name).aggregate(sum_miles=Sum('miles'))['sum_miles']
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