client: don't emit task shutdown delay event if not waiting (#16281)

.changelog/16281.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+client: Don't emit shutdown delay task event when the shutdown operation is configured to skip the delay
+```

client/allocrunner/taskrunner/task_runner.go

@@ -985,10 +985,16 @@ func (tr *TaskRunner) handleKill(resultCh <-chan *drivers.ExitResult) *drivers.E
 	// This allows for things like service de-registration to run
 	// before waiting to kill task
 	if delay := tr.Task().ShutdownDelay; delay != 0 {
+		var ev *structs.TaskEvent
+		if tr.alloc.DesiredTransition.ShouldIgnoreShutdownDelay() {
+			tr.logger.Debug("skipping shutdown_delay", "shutdown_delay", delay)
+			ev = structs.NewTaskEvent(structs.TaskSkippingShutdownDelay).
+				SetDisplayMessage(fmt.Sprintf("Skipping shutdown_delay of %s before killing the task.", delay))
+		} else {
 			tr.logger.Debug("waiting before killing task", "shutdown_delay", delay)
-
-		ev := structs.NewTaskEvent(structs.TaskWaitingShuttingDownDelay).
+			ev = structs.NewTaskEvent(structs.TaskWaitingShuttingDownDelay).
 				SetDisplayMessage(fmt.Sprintf("Waiting for shutdown_delay of %s before killing the task.", delay))
+		}
 		tr.UpdateState(structs.TaskStatePending, ev)
 
 		select {

client/allocrunner/taskrunner/task_runner_test.go

@@ -1107,7 +1107,17 @@ func TestTaskRunner_NoShutdownDelay(t *testing.T) {
 	}
 
 	err := <-killed
-	require.NoError(t, err, "killing task returned unexpected error")
+	must.NoError(t, err)
+
+	// Check that we only emit the expected events.
+	hasEvent := false
+	for _, ev := range tr.state.Events {
+		must.NotEq(t, structs.TaskWaitingShuttingDownDelay, ev.Type)
+		if ev.Type == structs.TaskSkippingShutdownDelay {
+			hasEvent = true
+		}
+	}
+	must.True(t, hasEvent)
 }
 
 // TestTaskRunner_Dispatch_Payload asserts that a dispatch job runs and the

nomad/structs/structs.go

@@ -8348,6 +8348,10 @@ const (
 	// TaskWaitingShuttingDownDelay indicates that the task is waiting for
 	// shutdown delay before being TaskKilled
 	TaskWaitingShuttingDownDelay = "Waiting for shutdown delay"
+
+	// TaskSkippingShutdownDelay indicates that the task operation was
+	// configured to ignore the shutdown delay value set for the tas.
+	TaskSkippingShutdownDelay = "Skipping shutdown delay"
 )
 
 // TaskEvent is an event that effects the state of a task and contains meta-data