onInvalidated static method
Returns a broadcast Stream that emits whenever queries matching key are invalidated.
Subscribed to by BloomQuery to trigger background re-fetching.
Implementation
static Stream<void> onInvalidated(List<dynamic> key) {
final keyStr = normalizeKey(key);
return _invalidationControllers
.putIfAbsent(keyStr, () => StreamController<void>.broadcast())
.stream;
}