serializer.py

==== SNIP ====

class DistanceSerializer(serializers.Serializer):
    km = serializers.FloatField()
    m = serializers.FloatField()
    mi = serializers.FloatField()
    ft = serializers.FloatField()


class SearchResultSerializer(serializers.Serializer):
    text = serializers.CharField()
    pub_date = serializers.DateTimeField()
    distance = fields.SerializerMethodField('_distance')
    content_type = fields.CharField(source='model_name')
    content_object = fields.SerializerMethodField('_content_object')

    def _content_object(self, obj):
        if obj.model_name == 'foo':
            return FoSerializer(obj.object, many=False, context=self.context).data
        if obj.model_name == 'bar':
            return BarSerializer(obj.object, many=False, context=self.context).data
        return {}

    def __init__(self,  *args, **kwargs):
        self.unit = kwargs.pop('unit', None)
        return super(SearchResultSerializer, self).__init__(*args, **kwargs)

    def _distance(self, obj):
        if self.unit:
            return {self.unit: getattr(obj.distance, self.unit)}
        try:
            return DistanceSerializer(obj.distance, many=False).data
        except Exception as e:
            ## Log this
            return {}

views.py

=== SNIP ===
class SearchView(generics.ListAPIView):
    permission_classes = (permissions.IsAuthenticated,)
    serializer_class = SearchResultSerializer


    def get_queryset(self, *args, **kwargs):
        # This will return a dict of the first known
        # unit of distance found in the query
        request = self.request
        results = EmptySearchQuerySet()

        if request.GET.get('q'):
            form = ModelSearchForm(request.QUERY_PARAMS, searchqueryset=None, load_all=True)

            if form.is_valid():
                query = form.cleaned_data['q']
                results = form.search()
        else:
            form = ModelSearchForm(searchqueryset=None, load_all=True)

        if results.query.backend.include_spelling:
            context['suggestion'] = form.get_suggestion()

        distance = None
        unit = None
        try:
            k,v = ((k,v) for k,v in request.QUERY_PARAMS.items() if k in D.UNITS.keys()).next()
            distance = {k:v}
            unit = k
        except Exception as e:
            logging.error(e)

        point = None
        try:
            point = Point(float(request.QUERY_PARAMS['latitude']), float(request.QUERY_PARAMS['longitude']))
        except Exception as e:
            logging.error(e)

        if distance and point:
            results = results or SearchQuerySet()
            results = results.dwithin('location', point, D(**distance)).distance('location', point)


        return results
        #return Response(SearchResultSerializer(sqs, many=True, unit=unit).data)