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

client/ui/event/event.go

@@ -0,0 +1,151 @@
+package event
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+
+	"fyne.io/fyne/v2"
+	"github.com/cenkalti/backoff/v4"
+	log "github.com/sirupsen/logrus"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+
+	"github.com/netbirdio/netbird/client/proto"
+	"github.com/netbirdio/netbird/client/system"
+)
+
+type Manager struct {
+	app  fyne.App
+	addr string
+
+	mu      sync.Mutex
+	ctx     context.Context
+	cancel  context.CancelFunc
+	enabled bool
+}
+
+func NewManager(app fyne.App, addr string) *Manager {
+	return &Manager{
+		app:  app,
+		addr: addr,
+	}
+}
+
+func (e *Manager) Start(ctx context.Context) {
+	e.mu.Lock()
+	e.ctx, e.cancel = context.WithCancel(ctx)
+	e.mu.Unlock()
+
+	expBackOff := backoff.WithContext(&backoff.ExponentialBackOff{
+		InitialInterval:     time.Second,
+		RandomizationFactor: backoff.DefaultRandomizationFactor,
+		Multiplier:          backoff.DefaultMultiplier,
+		MaxInterval:         10 * time.Second,
+		MaxElapsedTime:      0,
+		Stop:                backoff.Stop,
+		Clock:               backoff.SystemClock,
+	}, ctx)
+
+	if err := backoff.Retry(e.streamEvents, expBackOff); err != nil {
+		log.Errorf("event stream ended: %v", err)
+	}
+}
+
+func (e *Manager) streamEvents() error {
+	e.mu.Lock()
+	ctx := e.ctx
+	e.mu.Unlock()
+
+	client, err := getClient(e.addr)
+	if err != nil {
+		return fmt.Errorf("create client: %w", err)
+	}
+
+	stream, err := client.SubscribeEvents(ctx, &proto.SubscribeRequest{})
+	if err != nil {
+		return fmt.Errorf("failed to subscribe to events: %w", err)
+	}
+
+	log.Info("subscribed to daemon events")
+	defer func() {
+		log.Info("unsubscribed from daemon events")
+	}()
+
+	for {
+		event, err := stream.Recv()
+		if err != nil {
+			return fmt.Errorf("error receiving event: %w", err)
+		}
+		e.handleEvent(event)
+	}
+}
+
+func (e *Manager) Stop() {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	if e.cancel != nil {
+		e.cancel()
+	}
+}
+
+func (e *Manager) SetNotificationsEnabled(enabled bool) {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	e.enabled = enabled
+}
+
+func (e *Manager) handleEvent(event *proto.SystemEvent) {
+	e.mu.Lock()
+	enabled := e.enabled
+	e.mu.Unlock()
+
+	if !enabled {
+		return
+	}
+
+	title := e.getEventTitle(event)
+	e.app.SendNotification(fyne.NewNotification(title, event.UserMessage))
+}
+
+func (e *Manager) getEventTitle(event *proto.SystemEvent) string {
+	var prefix string
+	switch event.Severity {
+	case proto.SystemEvent_ERROR, proto.SystemEvent_CRITICAL:
+		prefix = "Error"
+	case proto.SystemEvent_WARNING:
+		prefix = "Warning"
+	default:
+		prefix = "Info"
+	}
+
+	var category string
+	switch event.Category {
+	case proto.SystemEvent_DNS:
+		category = "DNS"
+	case proto.SystemEvent_NETWORK:
+		category = "Network"
+	case proto.SystemEvent_AUTHENTICATION:
+		category = "Authentication"
+	case proto.SystemEvent_CONNECTIVITY:
+		category = "Connectivity"
+	default:
+		category = "System"
+	}
+
+	return fmt.Sprintf("%s: %s", prefix, category)
+}
+
+func getClient(addr string) (proto.DaemonServiceClient, error) {
+	conn, err := grpc.NewClient(
+		strings.TrimPrefix(addr, "tcp://"),
+		grpc.WithTransportCredentials(insecure.NewCredentials()),
+		grpc.WithUserAgent(system.GetDesktopUIUserAgent()),
+	)
+	if err != nil {
+		return nil, err
+	}
+	return proto.NewDaemonServiceClient(conn), nil
+}