Fix/connection listener (#777)

Fix add/remove connection listener

In case we call the RemoveConnListener from Java then
we lose the reference from the original instance

client/android/client.go

@@ -118,12 +118,12 @@ func (c *Client) PeersList() *PeerInfoArray {
 	return &PeerInfoArray{items: peerInfos}
 }
 
-// AddConnectionListener add new network connection listener
-func (c *Client) AddConnectionListener(listener ConnectionListener) {
-	c.recorder.AddConnectionListener(listener)
+// SetConnectionListener set the network connection listener
+func (c *Client) SetConnectionListener(listener ConnectionListener) {
+	c.recorder.SetConnectionListener(listener)
 }
 
 // RemoveConnectionListener remove connection listener
-func (c *Client) RemoveConnectionListener(listener ConnectionListener) {
-	c.recorder.RemoveConnectionListener(listener)
+func (c *Client) RemoveConnectionListener() {
+	c.recorder.RemoveConnectionListener()
 }

client/internal/peer/notifier.go

@@ -14,32 +14,31 @@ const (
 type notifier struct {
 	serverStateLock    sync.Mutex
 	listenersLock      sync.Mutex
-	listeners          map[Listener]struct{}
+	listener           Listener
 	currentServerState bool
 	currentClientState bool
 	lastNotification   int
 }
 
 func newNotifier() *notifier {
-	return &notifier{
-		listeners: make(map[Listener]struct{}),
-	}
+	return &notifier{}
 }
 
-func (n *notifier) addListener(listener Listener) {
+func (n *notifier) setListener(listener Listener) {
 	n.listenersLock.Lock()
 	defer n.listenersLock.Unlock()
 
 	n.serverStateLock.Lock()
-	go n.notifyListener(listener, n.lastNotification)
+	n.notifyListener(listener, n.lastNotification)
 	n.serverStateLock.Unlock()
-	n.listeners[listener] = struct{}{}
+
+	n.listener = listener
 }
 
-func (n *notifier) removeListener(listener Listener) {
+func (n *notifier) removeListener() {
 	n.listenersLock.Lock()
 	defer n.listenersLock.Unlock()
-	delete(n.listeners, listener)
+	n.listener = nil
 }
 
 func (n *notifier) updateServerStates(mgmState bool, signalState bool) {
@@ -64,7 +63,7 @@ func (n *notifier) updateServerStates(mgmState bool, signalState bool) {
 	}
 
 	n.lastNotification = n.calculateState(newState, n.currentClientState)
-	go n.notifyAll(n.lastNotification)
+	n.notify(n.lastNotification)
 }
 
 func (n *notifier) clientStart() {
@@ -72,7 +71,7 @@ func (n *notifier) clientStart() {
 	defer n.serverStateLock.Unlock()
 	n.currentClientState = true
 	n.lastNotification = n.calculateState(n.currentServerState, true)
-	go n.notifyAll(n.lastNotification)
+	n.notify(n.lastNotification)
 }
 
 func (n *notifier) clientStop() {
@@ -80,7 +79,7 @@ func (n *notifier) clientStop() {
 	defer n.serverStateLock.Unlock()
 	n.currentClientState = false
 	n.lastNotification = n.calculateState(n.currentServerState, false)
-	go n.notifyAll(n.lastNotification)
+	n.notify(n.lastNotification)
 }
 
 func (n *notifier) clientTearDown() {
@@ -88,33 +87,35 @@ func (n *notifier) clientTearDown() {
 	defer n.serverStateLock.Unlock()
 	n.currentClientState = false
 	n.lastNotification = stateDisconnecting
-	go n.notifyAll(n.lastNotification)
+	n.notify(n.lastNotification)
 }
 
 func (n *notifier) isServerStateChanged(newState bool) bool {
 	return n.currentServerState != newState
 }
 
-func (n *notifier) notifyAll(state int) {
+func (n *notifier) notify(state int) {
 	n.listenersLock.Lock()
 	defer n.listenersLock.Unlock()
-
-	for l := range n.listeners {
-		n.notifyListener(l, state)
+	if n.listener == nil {
+		return
 	}
+	n.notifyListener(n.listener, state)
 }
 
 func (n *notifier) notifyListener(l Listener, state int) {
-	switch state {
-	case stateDisconnected:
-		l.OnDisconnected()
-	case stateConnected:
-		l.OnConnected()
-	case stateConnecting:
-		l.OnConnecting()
-	case stateDisconnecting:
-		l.OnDisconnecting()
-	}
+	go func() {
+		switch state {
+		case stateDisconnected:
+			l.OnDisconnected()
+		case stateConnected:
+			l.OnConnected()
+		case stateConnecting:
+			l.OnConnecting()
+		case stateDisconnecting:
+			l.OnDisconnecting()
+		}
+	}()
 }
 
 func (n *notifier) calculateState(serverState bool, clientState bool) int {
@@ -132,17 +133,17 @@ func (n *notifier) calculateState(serverState bool, clientState bool) int {
 func (n *notifier) peerListChanged(numOfPeers int) {
 	n.listenersLock.Lock()
 	defer n.listenersLock.Unlock()
-
-	for l := range n.listeners {
-		l.OnPeersListChanged(numOfPeers)
+	if n.listener == nil {
+		return
 	}
+	n.listener.OnPeersListChanged(numOfPeers)
 }
 
 func (n *notifier) localAddressChanged(fqdn, address string) {
 	n.listenersLock.Lock()
 	defer n.listenersLock.Unlock()
-
-	for l := range n.listeners {
-		l.OnAddressChanged(fqdn, address)
+	if n.listener == nil {
+		return
 	}
+	n.listener.OnAddressChanged(fqdn, address)
 }

client/internal/peer/notifier_test.go

@@ -1,9 +1,48 @@
 package peer
 
 import (
+	"sync"
 	"testing"
 )
 
+type mocListener struct {
+	lastState int
+	wg        sync.WaitGroup
+	peers     int
+}
+
+func (l *mocListener) OnConnected() {
+	l.lastState = stateConnected
+	l.wg.Done()
+}
+func (l *mocListener) OnDisconnected() {
+	l.lastState = stateDisconnected
+	l.wg.Done()
+}
+func (l *mocListener) OnConnecting() {
+	l.lastState = stateConnecting
+	l.wg.Done()
+}
+func (l *mocListener) OnDisconnecting() {
+	l.lastState = stateDisconnecting
+	l.wg.Done()
+}
+
+func (l *mocListener) OnAddressChanged(host, addr string) {
+
+}
+func (l *mocListener) OnPeersListChanged(size int) {
+	l.peers = size
+}
+
+func (l *mocListener) setWaiter() {
+	l.wg.Add(1)
+}
+
+func (l *mocListener) wait() {
+	l.wg.Wait()
+}
+
 func Test_notifier_serverState(t *testing.T) {
 
 	type scenario struct {
@@ -30,3 +69,30 @@ func Test_notifier_serverState(t *testing.T) {
 		})
 	}
 }
+
+func Test_notifier_SetListener(t *testing.T) {
+	listener := &mocListener{}
+	listener.setWaiter()
+
+	n := newNotifier()
+	n.lastNotification = stateConnecting
+	n.setListener(listener)
+	listener.wait()
+	if listener.lastState != n.lastNotification {
+		t.Errorf("invalid state: %d, expected: %d", listener.lastState, n.lastNotification)
+	}
+}
+
+func Test_notifier_RemoveListener(t *testing.T) {
+	listener := &mocListener{}
+	listener.setWaiter()
+	n := newNotifier()
+	n.lastNotification = stateConnecting
+	n.setListener(listener)
+	n.removeListener()
+	n.peerListChanged(1)
+
+	if listener.peers != 0 {
+		t.Errorf("invalid state: %d", listener.peers)
+	}
+}

client/internal/peer/status.go

@@ -293,14 +293,14 @@ func (d *Status) ClientTeardown() {
 	d.notifier.clientTearDown()
 }
 
-// AddConnectionListener add a listener to the notifier
-func (d *Status) AddConnectionListener(listener Listener) {
-	d.notifier.addListener(listener)
+// SetConnectionListener set a listener to the notifier
+func (d *Status) SetConnectionListener(listener Listener) {
+	d.notifier.setListener(listener)
 }
 
-// RemoveConnectionListener remove a listener from the notifier
-func (d *Status) RemoveConnectionListener(listener Listener) {
-	d.notifier.removeListener(listener)
+// RemoveConnectionListener remove the listener from the notifier
+func (d *Status) RemoveConnectionListener() {
+	d.notifier.removeListener()
 }
 
 func (d *Status) onConnectionChanged() {