[client] Fix controller re-connection (#2758)

Rethink the peer reconnection implementation

signal/client/client.go

@@ -35,6 +35,7 @@ type Client interface {
 	WaitStreamConnected()
 	SendToStream(msg *proto.EncryptedMessage) error
 	Send(msg *proto.Message) error
+	SetOnReconnectedListener(func())
 }
 
 // UnMarshalCredential parses the credentials from the message and returns a Credential instance

signal/client/grpc.go

@@ -43,6 +43,8 @@ type GrpcClient struct {
 
 	connStateCallback     ConnStateNotifier
 	connStateCallbackLock sync.RWMutex
+
+	onReconnectedListenerFn func()
 }
 
 func (c *GrpcClient) StreamConnected() bool {
@@ -181,12 +183,17 @@ func (c *GrpcClient) notifyStreamDisconnected() {
 func (c *GrpcClient) notifyStreamConnected() {
 	c.mux.Lock()
 	defer c.mux.Unlock()
+
 	c.status = StreamConnected
 	if c.connectedCh != nil {
 		// there are goroutines waiting on this channel -> release them
 		close(c.connectedCh)
 		c.connectedCh = nil
 	}
+
+	if c.onReconnectedListenerFn != nil {
+		c.onReconnectedListenerFn()
+	}
 }
 
 func (c *GrpcClient) getStreamStatusChan() <-chan struct{} {
@@ -271,6 +278,13 @@ func (c *GrpcClient) WaitStreamConnected() {
 	}
 }
 
+func (c *GrpcClient) SetOnReconnectedListener(fn func()) {
+	c.mux.Lock()
+	defer c.mux.Unlock()
+
+	c.onReconnectedListenerFn = fn
+}
+
 // SendToStream sends a message to the remote Peer through the Signal Exchange using established stream connection to the Signal Server
 // The GrpcClient.Receive method must be called before sending messages to establish initial connection to the Signal Exchange
 // GrpcClient.connWg can be used to wait

signal/client/mock.go

@@ -7,14 +7,20 @@ import (
 )
 
 type MockClient struct {
-	CloseFunc               func() error
-	GetStatusFunc           func() Status
-	StreamConnectedFunc     func() bool
-	ReadyFunc               func() bool
-	WaitStreamConnectedFunc func()
-	ReceiveFunc             func(ctx context.Context, msgHandler func(msg *proto.Message) error) error
-	SendToStreamFunc        func(msg *proto.EncryptedMessage) error
-	SendFunc                func(msg *proto.Message) error
+	CloseFunc                    func() error
+	GetStatusFunc                func() Status
+	StreamConnectedFunc          func() bool
+	ReadyFunc                    func() bool
+	WaitStreamConnectedFunc      func()
+	ReceiveFunc                  func(ctx context.Context, msgHandler func(msg *proto.Message) error) error
+	SendToStreamFunc             func(msg *proto.EncryptedMessage) error
+	SendFunc                     func(msg *proto.Message) error
+	SetOnReconnectedListenerFunc func(f func())
+}
+
+// SetOnReconnectedListener sets the function to be called when the client reconnects.
+func (sm *MockClient) SetOnReconnectedListener(_ func()) {
+	// Do nothing
 }
 
 func (sm *MockClient) IsHealthy() bool {