Add status change event

Will propagated to client via SSE in ith own channel, to inform clients about CRC status change.
Status modified in "status_change_stream.go", as current status implementation has no single point of change, so tracking transition between states is challenging.

Signed-off-by: Yevhen Vydolob <[email protected]>

Author: evidolob

pkg/crc/api/events/event_server.go

@@ -56,6 +56,7 @@ func NewEventServer(machine machine.Client) *EventServer {
 
 	sseServer.CreateStream(Logs)
 	sseServer.CreateStream(ClusterLoad)
+	sseServer.CreateStream(StatusChange)
 	return eventServer
 }
 
@@ -69,6 +70,8 @@ func createEventStream(server *EventServer, streamID string) EventStream {
 		return newLogsStream(server)
 	case ClusterLoad:
 		return newClusterLoadStream(server)
+	case StatusChange:
+		return newStatusChangeStream(server)
 	}
 	return nil
 }

pkg/crc/api/events/events.go

@@ -3,8 +3,9 @@ package events
 import "github.com/r3labs/sse/v2"
 
 const (
-	Logs        = "logs"         // Logs event channel, contains daemon logs
-	ClusterLoad = "cluster_load" // status event channel, contains VM load info
+	Logs         = "logs"          // Logs event channel, contains daemon logs
+	ClusterLoad  = "cluster_load"  // status event channel, contains VM load info
+	StatusChange = "status_change" // status change channel, fires on 'starting', 'stopping', etc
 )
 
 type EventPublisher interface {

pkg/crc/api/events/status_change_stream.go

@@ -0,0 +1,69 @@
+package events
+
+import (
+	"encoding/json"
+
+	"github.com/crc-org/crc/v2/pkg/crc/logging"
+	"github.com/crc-org/crc/v2/pkg/crc/machine"
+	"github.com/crc-org/crc/v2/pkg/crc/machine/state"
+	"github.com/crc-org/crc/v2/pkg/crc/machine/types"
+	"github.com/crc-org/crc/v2/pkg/events"
+	"github.com/r3labs/sse/v2"
+)
+
+type serializableEvent struct {
+	Status *types.ClusterStatusResult `json:"status"`
+	Error  string                     `json:"error,omitempty"`
+}
+
+type statusChangeListener struct {
+	machineClient machine.Client
+	publisher     EventPublisher
+}
+
+func newStatusChangeStream(server *EventServer) EventStream {
+	return newStream(newStatusChangeListener(server.machine), newEventPublisher(StatusChange, server.sseServer))
+}
+
+func newStatusChangeListener(client machine.Client) EventProducer {
+	return &statusChangeListener{
+		machineClient: client,
+	}
+}
+
+func (st *statusChangeListener) Notify(changedEvent events.StatusChangedEvent) {
+	logging.Debugf("State Changed Event %s", changedEvent)
+	var event serializableEvent
+	status, err := st.machineClient.Status()
+	// if we cannot receive actual state, send error state with error description
+	if err != nil {
+		event = serializableEvent{Status: &types.ClusterStatusResult{
+			CrcStatus: state.Error,
+		}, Error: err.Error()}
+	} else {
+		// event could be fired, before actual code, which change state is called
+		// so status could contain 'old' state, replace it with state received in event
+		status.CrcStatus = changedEvent.State // override with actual reported state
+		event = serializableEvent{Status: status}
+		if changedEvent.Error != nil {
+			event.Error = changedEvent.Error.Error()
+		}
+
+	}
+	data, err := json.Marshal(event)
+	if err != nil {
+		logging.Errorf("Could not serealize status changed event in to JSON: %s", err)
+		return
+	}
+	st.publisher.Publish(&sse.Event{Event: []byte(StatusChange), Data: data})
+}
+
+func (st *statusChangeListener) Start(publisher EventPublisher) {
+	st.publisher = publisher
+	events.StatusChanged.AddListener(st)
+
+}
+
+func (st *statusChangeListener) Stop() {
+	events.StatusChanged.RemoveListener(st)
+}

pkg/crc/machine/sync.go

@@ -10,6 +10,7 @@ import (
 	"github.com/crc-org/crc/v2/pkg/crc/machine/state"
 	"github.com/crc-org/crc/v2/pkg/crc/machine/types"
 	crcPreset "github.com/crc-org/crc/v2/pkg/crc/preset"
+	"github.com/crc-org/crc/v2/pkg/events"
 )
 
 const startCancelTimeout = 15 * time.Second
@@ -69,6 +70,10 @@ func (s *Synchronized) Delete() error {
 
 	err := s.underlying.Delete()
 	s.syncOperationDone <- Deleting
+
+	if err == nil {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: state.NoVM})
+	}
 	return err
 }
 
@@ -80,6 +85,7 @@ func (s *Synchronized) prepareStart(startCancel context.CancelFunc) error {
 	}
 	s.startCancel = startCancel
 	s.currentState = Starting
+	events.StatusChanged.Fire(events.StatusChangedEvent{State: state.Starting})
 
 	return nil
 }
@@ -92,6 +98,13 @@ func (s *Synchronized) Start(ctx context.Context, startConfig types.StartConfig)
 
 	startResult, err := s.underlying.Start(ctx, startConfig)
 	s.syncOperationDone <- Starting
+
+	if err == nil {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: startResult.Status})
+	} else {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: state.Error, Error: err})
+	}
+
 	return startResult, err
 }
 
@@ -136,10 +149,16 @@ func (s *Synchronized) Stop() (state.State, error) {
 	if err := s.prepareStopDelete(Stopping); err != nil {
 		return state.Error, err
 	}
+	events.StatusChanged.Fire(events.StatusChangedEvent{State: state.Stopping})
 
 	st, err := s.underlying.Stop()
 	s.syncOperationDone <- Stopping
 
+	if err == nil {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: st})
+	} else {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: state.Error, Error: err})
+	}
 	return st, err
 }
 
@@ -160,7 +179,14 @@ func (s *Synchronized) ConnectionDetails() (*types.ConnectionDetails, error) {
 }
 
 func (s *Synchronized) PowerOff() error {
-	return s.underlying.PowerOff()
+	err := s.underlying.PowerOff()
+	if err != nil {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: state.Stopped})
+	} else {
+		events.StatusChanged.Fire(events.StatusChangedEvent{State: state.Error, Error: err})
+	}
+
+	return err
 }
 
 func (s *Synchronized) Status() (*types.ClusterStatusResult, error) {

pkg/events/events.go

@@ -0,0 +1,14 @@
+package events
+
+import (
+	"github.com/crc-org/crc/v2/pkg/crc/machine/state"
+)
+
+type StatusChangedEvent struct {
+	State state.State
+	Error error
+}
+
+var (
+	StatusChanged = NewEvent[StatusChangedEvent]()
+)