Remove spawn_after

It was a naive implementation it is replaced with
StaticallyDelayingCancellableTaskExecutorWrapper.

Signed-off-by: Balazs Gibizer <gibi@redhat.com>
Change-Id: I5e8d496473d4ec167d1655368a00cbfa78d2c074

nova/tests/unit/test_utils.py

@@ -1560,18 +1560,6 @@ class SpawnOnTestCase(test.NoDBTestCase):
             'test_spawn_on_warns_on_full_executor.cell_worker', task)
 
 
-class SpawnAfterTestCase(test.NoDBTestCase):
-    @mock.patch.object(time, "sleep")
-    def test_spawn_after_submits_work_after_delay(self, mock_sleep):
-        task = mock.MagicMock()
-
-        future = utils.spawn_after(0.1, task, 13, foo='bar')
-        future.result()
-
-        task.assert_called_once_with(13, foo='bar')
-        mock_sleep.assert_called_once_with(0.1)
-
-
 class ExecutorStatsTestCase(test.NoDBTestCase):
 
     def setUp(self):

nova/utils.py

@@ -587,20 +587,6 @@ def spawn(
     return spawn_on(_get_default_executor(), func, *args, **kwargs)
 
 
-def spawn_after(
-    seconds: float,
-    func: ty.Callable[..., ty.Any],
-    *args: ty.Any, **kwargs: ty.Any
-) -> futurist.Future:
-    """Executing the function asynchronously after the given time."""
-
-    def delayed(*args, **kwargs):
-        time.sleep(seconds)
-        return func(*args, **kwargs)
-
-    return spawn(delayed, *args, **kwargs)
-
-
 def _executor_is_full(executor: Executor) -> bool:
     if concurrency_mode_threading():
         # TODO(gibi): Move this whole logic to futurist ThreadPoolExecutor