urls.py

sqs = SearchQuerySet()
for field_name, field in ProductIndex.fields.items():
    if field.faceted is True:
        # Ensure we facet the results set by the defined facetable fields
        sqs.facet(field_name)

urlpatterns = patterns('search.apps.views',
    url(r'^suggest/$', Suggestions.as_view(), name='oscar-search-suggest'),
    url(r'^$', FacetedSearchView(form_class=FacetedSearchForm,
        searchqueryset=sqs), name='oscar-search'),
)

indexes.py

class AbstractProductIndex(SearchIndex):
    text = EdgeNgramField(document=True, use_template=True, template_name='oscar/search/indexes/product/item_text.txt')
    title = EdgeNgramField(model_attr='title')
    upc = CharField(model_attr="upc")
    item_class = CharField(model_attr="item_class", faceted=True)
    score = FloatField(model_attr="score")
    date_created = DateTimeField(model_attr='date_created')
    date_updated = DateTimeField(model_attr='date_updated')
    ...