[client] Add UI client event notifications (#3207)

client/server/event.go

@@ -0,0 +1,36 @@
+package server
+
+import (
+	"context"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/proto"
+)
+
+func (s *Server) SubscribeEvents(req *proto.SubscribeRequest, stream proto.DaemonService_SubscribeEventsServer) error {
+	subscription := s.statusRecorder.SubscribeToEvents()
+	defer func() {
+		s.statusRecorder.UnsubscribeFromEvents(subscription)
+		log.Debug("client unsubscribed from events")
+	}()
+
+	log.Debug("client subscribed to events")
+
+	for {
+		select {
+		case event := <-subscription.Events():
+			if err := stream.Send(event); err != nil {
+				log.Warnf("error sending event to %v: %v", req, err)
+				return err
+			}
+		case <-stream.Context().Done():
+			return nil
+		}
+	}
+}
+
+func (s *Server) GetEvents(context.Context, *proto.GetEventsRequest) (*proto.GetEventsResponse, error) {
+	events := s.statusRecorder.GetEventHistory()
+	return &proto.GetEventsResponse{Events: events}, nil
+}