djangorestframework-gis-distance 1.0.0

Regular implementation

First include DistanceField in your serializer.

from restframework_gis_distance.fields import DistanceField

class RecordSerializer(serializers.ModelSerializer):
    distance = DistanceField(unit='m')

    class Meta:
        model = Record
        fields = ('location', 'title', 'created', 'distance')

Then use the filter OrderedDistanceToPointFilter in your view.

from restframework_gis_distance.filters import OrderedDistanceToPointFilter

class RecordListView(mixins.ListModelMixin, generics.GenericAPIView):
    permission_classes = (AllowAny,)
    serializer_class = RecordSerializer
    queryset = Record.objects.all()
    filter_backends = (OrderedDistanceToPointFilter,)
    distance_filter_field = 'location'
    distance_filter_convert_meters = True
    distance_filter_add_distance = True

After this, set up your urls as usual and call your endpoint like this: example.com/api/endpoint/?dist=1000&point=long,lat

Optional field

Using distance as a optional field (for the cases when you only want to display distance when geo coordinates is supplied)

Instead of declaring a straight DistanceField, wrap the DistanceField as a SerializerMethodField, like this:

from restframework_gis_distance.filters import OrderedDistanceToPointFilter

class RecordOptionalSerializer(serializers.ModelSerializer):
    distance = serializers.SerializerMethodField()

    class Meta:
        model = Record
        fields = ('location', 'title', 'created', 'distance')

    def get_distance(self, obj):
        distance = getattr(obj, "distance", None)
        return DistanceField(unit='m').to_representation(distance)