Queryset based on request

[stevelacey]

I am just upgrading to DRF 3.0, and I am pretty much there.

One thing for the upgrade docs / helping me... how do I contextualise the queryset now required for related fields to the request?

At ViewSet level, for the results, remains easy:

    def get_queryset(self):
        if self.request.user.is_staff:
            queryset = Book.objects.all()
        else:
            queryset = self.request.user.library.books.all()

        return queryset

But when customising the choices for a relation in a serializer:

    book = SlugRelatedField(queryset=Book.objects.all(), slug_field='isbn')
    #                                    ^ how request here? lambda... magic?

[tomchristie]

Conversation on this here: #1985.
You can dynamically alter the .fields attribute on a serializer instance, so you could modify your serializer .__init__ in order to do this, but we do need a better answer to this, which will probably be a part of dealing with #1811.
Closing this issue off in preference of those existing ones.

[stevelacey]

Overriding __init__ in my serializer worked a treat, thanks:

    def __init__(self, *args, **kwargs):
        user = kwargs['context']['request'].user

        if not user.is_staff:
            book_f = self.fields['book']

            book_f.queryset = book_f.queryset.filter(organisation=user.organisation)

        super(ExampleSerializer, self).__init__(*args, **kwargs)

[stevelacey]

@tomchristie is there any better approach for this yet? I am running into a bunch of issues caused largely by requiring the request in serializers – e.g. django-rest-swagger wants to access the fields for introspection and doesn't pass a context along

[tomchristie]

e.g. django-rest-swagger wants to access the fields for introspection and doesn't pass a context along

In which case I'd suggest overriding get_serializer instead, and modifying the field at that point.
That way it's happening in the context of a view, rather than implicitly requiring request in the context.