Problem using serializer with Dumpdata

[JustinKellogg]

When I run dumpdata with geojson it doesn't detect any features.

Looked into it a bit and dumpdata passes a generator object to the serialize methods, and this serializer seems to expect queryset-like objects.

[leplatrem]

It should work with lists, but indeed, not sure with generators...
https://github.com/makinacorpus/django-geojson/blob/master/djgeojson/serializers.py#L346-L347

Instead of isinstance(queryset, list), we could check something like hasattr(queryset, '__iter__'). Don't hesitate to open a pull-request !

[JustinKellogg]

Leaving this here as a reference for how dumpdata calls the serializers
https://github.com/django/django/blob/master/django/core/management/commands/dumpdata.py#L139
https://github.com/django/django/blob/master/django/core/management/commands/dumpdata.py#L160