fix: prevented from sending status change on service start if there was no last known status

Author: exelban

pkg/monitor/watcher.go

@@ -46,6 +46,9 @@ func (w *watcher) run(ctx context.Context) {
 	if len(incidents) > 0 && incidents[0].EndTS == nil {
 		w.incident = incidents[0]
 	}
+	if lastResponse, err := w.store.LastResponse(ctx, w.host.ID); err == nil && lastResponse != nil {
+		w.status = lastResponse.StatusType
+	}
 
 	log.Printf("[INFO] %s: new watcher", w.host.String())
 
@@ -96,7 +99,7 @@ func (w *watcher) validate(resp *types.HttpResponse) {
 		if w.successCount >= w.host.SuccessThreshold {
 			newStatus := types.UP
 			if w.status != types.Unknown && w.status != types.UP {
-				if err := w.notify.Set(w.host.Alerts, newStatus, w.host.String()); err != nil {
+				if err := w.notify.Send(w.host, newStatus); err != nil {
 					log.Print(err)
 				}
 
@@ -122,9 +125,10 @@ func (w *watcher) validate(resp *types.HttpResponse) {
 		if w.failureCount >= w.host.FailureThreshold {
 			newStatus := types.DOWN
 			if w.status != types.Unknown && w.status != types.DOWN {
-				if err := w.notify.Set(w.host.Alerts, newStatus, w.host.String()); err != nil {
+				if err := w.notify.Send(w.host, newStatus); err != nil {
 					log.Print(err)
 				}
+
 				if w.incident == nil {
 					w.incident = &types.Incident{
 						Details: types.IncidentDetails{

store/bolt.go

@@ -83,6 +83,29 @@ func (b *Bolt) FindResponses(ctx context.Context, hostID string) ([]*types.HttpR
 
 	return res, err
 }
+func (b *Bolt) LastResponse(ctx context.Context, hostID string) (*types.HttpResponse, error) {
+	var res *types.HttpResponse
+
+	err := b.conn.View(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket([]byte(hostID))
+		if bucket == nil {
+			return nil
+		}
+		c := bucket.Cursor()
+		k, v := c.Last()
+		if k == nil {
+			return nil
+		}
+		var r types.HttpResponse
+		if err := json.Unmarshal(v, &r); err != nil {
+			return err
+		}
+		res = &r
+		return nil
+	})
+
+	return res, err
+}
 
 func (b *Bolt) Hosts(ctx context.Context) ([]string, error) {
 	keys := []string{}

store/memory.go

@@ -73,6 +73,23 @@ func (m *Memory) FindResponses(ctx context.Context, hostID string) ([]*types.Htt
 
 	return res, nil
 }
+func (m *Memory) LastResponse(ctx context.Context, hostID string) (*types.HttpResponse, error) {
+	m.RLock()
+	defer m.RUnlock()
+
+	if _, ok := m.history[hostID]; !ok {
+		return nil, nil
+	}
+
+	var last *types.HttpResponse
+	for _, r := range m.history[hostID] {
+		if last == nil || r.Timestamp.After(last.Timestamp) {
+			last = r
+		}
+	}
+
+	return last, nil
+}
 
 func (m *Memory) Hosts(ctx context.Context) ([]string, error) {
 	m.RLock()

store/store.go

@@ -18,6 +18,7 @@ type Interface interface {
 	AddResponse(ctx context.Context, hostID string, r *types.HttpResponse) error
 	DeleteResponse(ctx context.Context, hostID string, keys []time.Time) error
 	FindResponses(ctx context.Context, hostID string) ([]*types.HttpResponse, error)
+	LastResponse(ctx context.Context, hostID string) (*types.HttpResponse, error)
 
 	// Hosts returns a list of all hosts that has any responses in the store.
 	Hosts(ctx context.Context) ([]string, error)