added state api

backend/cron/cron_state_checker.py

@@ -22,6 +22,11 @@ T = TypeVar('T')
 
 
 class StateChecker(Generic[T]):
+    """
+    This class is designed generically to regularly check the state of objects with given function(s).
+    The determined state is stored "locally" in the state checker object and NOT reflected back to the checked objects!
+    It can be retrieved by calling get_current_state.
+    """
     def __init__(self, state_checker_func: Union[Callable, List[Callable]], type_to_check: T, type_name=None,
                  threads=NUM_THREADS):
         self.num_threads = threads
@@ -135,7 +140,6 @@ class StateChecker(Generic[T]):
                     'previous': {'state_ok': self.state_results[o_s]['state_ok'],
                                  'msg': self.state_results[o_s].get('msg', None),
                                  'time_stamp': self.state_results[o_s].get('time_stamp', None)}}
-                pass
             else:
                 self.state_results[o_s] = object_states[o_s]