feat(tailscale): add Tailscale control center widget (#1875)

* feat(tailscale): add Tailscale control center widget Full-stack Tailscale integration for DMS control center: Backend (Go): - Event-driven manager via WatchIPNBus (no polling) - Reconnects with exponential backoff when tailscaled unavailable - Typed conversion from ipnstate.Status to QML-friendly IPC types - Testable via tailscaleClient interface with mock watcher - Manager cleanup in cleanupManagers() - 19 unit tests Frontend (QML): - TailscaleService with WebSocket subscription - TailscaleWidget with peer list, filter chips, search - Copy-to-clipboard for IPs and DNS names - Daemon lifecycle handling (offline/stopped states) Dependencies: - Add tailscale.com v1.96.1 (official local API client) - Bump Go to 1.26.1 (required by tailscale.com) * cleanups --------- Co-authored-by: bbedward <bbedward@gmail.com>
2026-05-13 07:42:46 -04:00 · 2026-05-04 19:37:25 +02:00
parent 408beb202c
commit d223a74740
19 changed files with 2055 additions and 11 deletions
@@ -0,0 +1,277 @@
+package tailscale
+
+import (
+	"context"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
+	"github.com/AvengeMedia/DankMaterialShell/core/pkg/syncmap"
+	"tailscale.com/client/local"
+	"tailscale.com/ipn"
+	"tailscale.com/ipn/ipnstate"
+)
+
+const (
+	statusTimeout  = 3 * time.Second
+	debounceWindow = 150 * time.Millisecond
+)
+
+// tailscaleClient abstracts the Tailscale local API for testing.
+type tailscaleClient interface {
+	WatchIPNBus(ctx context.Context, mask ipn.NotifyWatchOpt) (ipnBusWatcher, error)
+	Status(ctx context.Context) (*ipnstate.Status, error)
+}
+
+// ipnBusWatcher abstracts the IPN bus watcher for testing.
+type ipnBusWatcher interface {
+	Next() (ipn.Notify, error)
+	Close() error
+}
+
+// localClientWrapper wraps local.Client to satisfy tailscaleClient.
+type localClientWrapper struct {
+	client *local.Client
+}
+
+func (w *localClientWrapper) WatchIPNBus(ctx context.Context, mask ipn.NotifyWatchOpt) (ipnBusWatcher, error) {
+	return w.client.WatchIPNBus(ctx, mask)
+}
+
+func (w *localClientWrapper) Status(ctx context.Context) (*ipnstate.Status, error) {
+	return w.client.Status(ctx)
+}
+
+// Manager manages Tailscale state via IPN bus events and subscriber notifications.
+type Manager struct {
+	state                *TailscaleState
+	stateMutex           sync.RWMutex
+	subscribers          syncmap.Map[string, chan TailscaleState]
+	client               tailscaleClient
+	ctx                  context.Context
+	cancel               context.CancelFunc
+	watchWG              sync.WaitGroup
+	closed               atomic.Bool
+	dirty                chan struct{}
+	available            atomic.Bool
+	availabilityCallback atomic.Pointer[func(bool)]
+}
+
+// NewManager creates a new Tailscale manager and starts watching the IPN bus.
+func NewManager(socketPath string) *Manager {
+	lc := &local.Client{Socket: socketPath}
+	return newManager(&localClientWrapper{client: lc})
+}
+
+func newManager(client tailscaleClient) *Manager {
+	ctx, cancel := context.WithCancel(context.Background())
+	m := &Manager{
+		state:  &TailscaleState{},
+		client: client,
+		ctx:    ctx,
+		cancel: cancel,
+		dirty:  make(chan struct{}, 1),
+	}
+
+	m.watchWG.Add(2)
+	go m.watchLoop(ctx)
+	go m.debounceLoop(ctx)
+
+	return m
+}
+
+func (m *Manager) watchLoop(ctx context.Context) {
+	defer m.watchWG.Done()
+
+	mask := ipn.NotifyInitialState | ipn.NotifyInitialNetMap | ipn.NotifyRateLimit
+	backoff := time.Second
+	unreachableSent := false
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		default:
+		}
+
+		watcher, err := m.client.WatchIPNBus(ctx, mask)
+		if err != nil {
+			if !unreachableSent {
+				m.updateState(&TailscaleState{Connected: false, BackendState: "Unreachable"})
+				unreachableSent = true
+			}
+			select {
+			case <-ctx.Done():
+				return
+			case <-time.After(backoff):
+			}
+			backoff = min(backoff*2, 30*time.Second)
+			continue
+		}
+
+		unreachableSent = false
+		backoff = time.Second
+		log.Info("[Tailscale] Connected to IPN bus")
+		m.markAvailable()
+
+		for {
+			notify, err := watcher.Next()
+			if err != nil {
+				log.Warnf("[Tailscale] IPN bus error: %v", err)
+				break
+			}
+
+			if notify.State == nil && notify.NetMap == nil {
+				continue
+			}
+			select {
+			case m.dirty <- struct{}{}:
+			default:
+			}
+		}
+
+		watcher.Close()
+	}
+}
+
+// debounceLoop coalesces rapid bus notifications into a single Status RPC
+// per debounceWindow, since NetMap events can fire many times per second
+// on busy tailnets.
+func (m *Manager) debounceLoop(ctx context.Context) {
+	defer m.watchWG.Done()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-m.dirty:
+		}
+
+		timer := time.NewTimer(debounceWindow)
+		collecting := true
+		for collecting {
+			select {
+			case <-ctx.Done():
+				timer.Stop()
+				return
+			case <-m.dirty:
+			case <-timer.C:
+				collecting = false
+			}
+		}
+
+		m.fetchAndBroadcast(ctx)
+	}
+}
+
+func (m *Manager) fetchAndBroadcast(ctx context.Context) {
+	statusCtx, cancel := context.WithTimeout(ctx, statusTimeout)
+	defer cancel()
+
+	status, err := m.client.Status(statusCtx)
+	if err != nil {
+		log.Warnf("[Tailscale] Failed to fetch status: %v", err)
+		return
+	}
+
+	state := convertStatus(status)
+	m.updateState(state)
+}
+
+func (m *Manager) updateState(state *TailscaleState) {
+	m.stateMutex.Lock()
+	m.state = state
+	m.stateMutex.Unlock()
+
+	m.broadcastState(*state)
+}
+
+func (m *Manager) broadcastState(state TailscaleState) {
+	if m.closed.Load() {
+		return
+	}
+	m.subscribers.Range(func(key string, ch chan TailscaleState) bool {
+		select {
+		case ch <- state:
+		default:
+		}
+		return true
+	})
+}
+
+// IsAvailable reports whether tailscaled has been reachable via the IPN bus
+// at least once since the manager started. False means tailscaled appears
+// to not be installed or has never been running.
+func (m *Manager) IsAvailable() bool {
+	return m.available.Load()
+}
+
+// SetAvailabilityCallback registers a callback fired when the manager
+// transitions from unavailable to available. Replaces any previously set
+// callback. Must be set before the manager has a chance to detect tailscaled.
+func (m *Manager) SetAvailabilityCallback(cb func(bool)) {
+	m.availabilityCallback.Store(&cb)
+}
+
+func (m *Manager) markAvailable() {
+	if m.available.Swap(true) {
+		return
+	}
+	if cb := m.availabilityCallback.Load(); cb != nil {
+		(*cb)(true)
+	}
+}
+
+// GetState returns a copy of the current Tailscale state.
+func (m *Manager) GetState() TailscaleState {
+	m.stateMutex.RLock()
+	defer m.stateMutex.RUnlock()
+
+	if m.state == nil {
+		return TailscaleState{}
+	}
+	return *m.state
+}
+
+// Subscribe creates a buffered channel for the given client ID.
+func (m *Manager) Subscribe(clientID string) chan TailscaleState {
+	ch := make(chan TailscaleState, 64)
+	m.subscribers.Store(clientID, ch)
+	return ch
+}
+
+// Unsubscribe removes and closes the subscriber channel.
+func (m *Manager) Unsubscribe(clientID string) {
+	if val, ok := m.subscribers.LoadAndDelete(clientID); ok {
+		close(val)
+	}
+}
+
+// Close stops the watch loop and closes all subscriber channels.
+func (m *Manager) Close() {
+	m.closed.Store(true)
+	m.cancel()
+	m.watchWG.Wait()
+
+	m.subscribers.Range(func(key string, ch chan TailscaleState) bool {
+		close(ch)
+		m.subscribers.Delete(key)
+		return true
+	})
+}
+
+// RefreshState triggers an immediate status fetch and broadcasts.
+func (m *Manager) RefreshState() {
+	ctx, cancel := context.WithTimeout(m.ctx, statusTimeout)
+	defer cancel()
+
+	status, err := m.client.Status(ctx)
+	if err != nil {
+		log.Warnf("[Tailscale] Failed to refresh state: %v", err)
+		return
+	}
+
+	state := convertStatus(status)
+	m.updateState(state)
+}