OCTRL-1049 Stop tasks within GO_ERROR transition (#756)

This moves stopping RUNNING tasks into GO_ERROR transition, so that the stop order makes sense - FLP and EPN tasks stop roughly in parallel.
Before, FLP tasks would be stopped only after EPN tasks, which was preventing EPNs to finalize certain computations and was generally opposite to the data flow.

I could not see any unwanted side effects of this change, seemed good on staging.

Author: knopers8

core/environment/environment.go

@@ -1236,22 +1236,6 @@ func (env *Environment) subscribeToWfState(taskman *task.Manager) {
 										env.setState(wfState.String())
 									}
 								}
-								toStop := env.Workflow().GetTasks().Filtered(func(t *task.Task) bool {
-									t.SetSafeToStop(true)
-									return t.IsSafeToStop()
-								})
-								if len(toStop) > 0 {
-									taskmanMessage := task.NewTransitionTaskMessage(
-										toStop,
-										sm.RUNNING.String(),
-										sm.STOP.String(),
-										sm.CONFIGURED.String(),
-										nil,
-										env.Id(),
-									)
-									taskman.MessageChannel <- taskmanMessage
-									<-env.stateChangedCh
-								}
 							})
 							break WORKFLOW_STATE_LOOP
 						}

core/environment/transition_goerror.go

@@ -26,6 +26,7 @@ package environment
 
 import (
 	"github.com/AliceO2Group/Control/core/task"
+	"github.com/AliceO2Group/Control/core/task/sm"
 )
 
 func NewGoErrorTransition(taskman *task.Manager) Transition {
@@ -42,7 +43,24 @@ type GoErrorTransition struct {
 }
 
 func (t GoErrorTransition) do(env *Environment) (err error) {
-	// We do not do anything here, because the error handling was already implemented elsewhere
-	// and we do not expose this transition to external calls (e.g. from the GUI).
+
+	// we stop all tasks which are in RUNNING
+	toStop := env.Workflow().GetTasks().Filtered(func(t *task.Task) bool {
+		t.SetSafeToStop(true)
+		return t.IsSafeToStop()
+	})
+	if len(toStop) > 0 {
+		taskmanMessage := task.NewTransitionTaskMessage(
+			toStop,
+			sm.RUNNING.String(),
+			sm.STOP.String(),
+			sm.CONFIGURED.String(),
+			nil,
+			env.Id(),
+		)
+		t.taskman.MessageChannel <- taskmanMessage
+		<-env.stateChangedCh
+	}
+
 	return
 }