def __init__(self, data, date, delta):
assert data, "data is required"
if len(data) > 0:
assert date, "date is required"
assert delta, "delta is required"
data = set(data)
model_class = type(lists.first(data))
assert lists.all(lambda e: type(e) == model_class, data), "data contain items of different types"
self.stored = model_class.objects.filter(pk__in=[e.id for e in data])
db = map(lambda e: dict(pk=e.id, date=date(e)), self.stored)
non_cached_entities = set(filter(lambda e: e.pk not in [x["pk"] for x in db], data))
self.cached = data - non_cached_entities
last_update_date = lambda e: filter(lambda x: x["pk"] == e.pk, db)[0]["date"]
expired_places = filter(lambda e: timezone.now() - last_update_date(e) > delta, self.cached)
self.for_insert = non_cached_entities
self.for_update = expired_places
def test_first(self):
self.assertEquals(lists.first([4, 2, 3]), 4)
self.assertEquals(lists.first(set([4, 5, 3, 'a', 18])), 'a')