Fix for #489 - disabled task shouldn't be allowed to start

mgmt/rest/task.go

@@ -42,8 +42,9 @@ var (
 	// The amount of time to buffer streaming events before flushing in seconds
 	StreamingBufferWindow = 0.1
 
-	ErrStreamingUnsupported = errors.New("Streaming unsupported")
-	ErrTaskNotFound         = errors.New("Task not found")
+	ErrStreamingUnsupported    = errors.New("Streaming unsupported")
+	ErrTaskNotFound            = errors.New("Task not found")
+	ErrTaskDisabledNotRunnable = errors.New("Task is disabled. Cannot be started")
 )
 
 type configItem struct {
@@ -240,6 +241,10 @@ func (s *Server) startTask(w http.ResponseWriter, r *http.Request, p httprouter.
 			respond(404, rbody.FromSnapErrors(errs), w)
 			return
 		}
+		if strings.Contains(errs[0].Error(), ErrTaskDisabledNotRunnable.Error()) {
+			respond(409, rbody.FromSnapErrors(errs), w)
+			return
+		}
 		respond(500, rbody.FromSnapErrors(errs), w)
 		return
 	}

scheduler/scheduler.go

@@ -39,10 +39,11 @@ import (
 var (
 	HandlerRegistrationName = "scheduler"
 
-	ErrMetricManagerNotSet = errors.New("MetricManager is not set.")
-	ErrSchedulerNotStarted = errors.New("Scheduler is not started.")
-	ErrTaskAlreadyRunning  = errors.New("Task is already running.")
-	ErrTaskAlreadyStopped  = errors.New("Task is already stopped.")
+	ErrMetricManagerNotSet     = errors.New("MetricManager is not set.")
+	ErrSchedulerNotStarted     = errors.New("Scheduler is not started.")
+	ErrTaskAlreadyRunning      = errors.New("Task is already running.")
+	ErrTaskAlreadyStopped      = errors.New("Task is already stopped.")
+	ErrTaskDisabledNotRunnable = errors.New("Task is disabled. Cannot be started.")
 )
 
 type schedulerState int
@@ -305,6 +306,14 @@ func (s *scheduler) startTask(id, source string) []serror.SnapError {
 		}
 	}
 
+	if t.state == core.TaskDisabled {
+		logger.WithFields(log.Fields{
+			"task-id": t.ID(),
+		}).Error("Task is disabled and must be enabled before starting")
+		return []serror.SnapError{
+			serror.New(ErrTaskDisabledNotRunnable),
+		}
+	}
 	if t.state == core.TaskFiring || t.state == core.TaskSpinning {
 		logger.WithFields(log.Fields{
 			"task-id":    t.ID(),

scheduler/scheduler_test.go

@@ -315,6 +315,17 @@ func TestScheduler(t *testing.T) {
 			So(err1, ShouldBeNil)
 			So(etsk.State(), ShouldEqual, core.TaskStopped)
 		})
+		Convey("Start disabled task", func() {
+			tsk, _ := s.CreateTask(schedule.NewSimpleSchedule(time.Millisecond*100), w, false)
+			So(tsk, ShouldNotBeNil)
+
+			t := s.tasks.Get(tsk.ID())
+			t.state = core.TaskDisabled
+
+			err := s.StartTask(tsk.ID())
+			So(err[0].Error(), ShouldResemble, "Task is disabled. Cannot be started.")
+			So(t.state, ShouldEqual, core.TaskDisabled)
+		})
 	})
 	Convey("Stop()", t, func() {
 		Convey("Should set scheduler state to SchedulerStopped", func() {