feat: returning to offline state on transport failure [MTT-4302]

Assets/Scripts/ConnectionManagement/ConnectionManager.cs

@@ -92,6 +92,7 @@ void Start()
             NetworkManager.OnClientDisconnectCallback += OnClientDisconnectCallback;
             NetworkManager.OnServerStarted += OnServerStarted;
             NetworkManager.ConnectionApprovalCallback += ApprovalCheck;
+            NetworkManager.OnTransportFailure += OnTransportFailure;
         }
 
         void OnDestroy()
@@ -100,7 +101,7 @@ void OnDestroy()
             NetworkManager.OnClientDisconnectCallback -= OnClientDisconnectCallback;
             NetworkManager.OnServerStarted -= OnServerStarted;
             NetworkManager.ConnectionApprovalCallback -= ApprovalCheck;
-
+            NetworkManager.OnTransportFailure -= OnTransportFailure;
         }
 
         internal void ChangeState(ConnectionState nextState)
@@ -135,6 +136,11 @@ void ApprovalCheck(NetworkManager.ConnectionApprovalRequest request, NetworkMana
             m_CurrentState.ApprovalCheck(request, response);
         }
 
+        void OnTransportFailure()
+        {
+            m_CurrentState.OnTransportFailure();
+        }
+
         public void StartClientLobby(string playerName)
         {
             m_CurrentState.StartClientLobby(playerName);

Assets/Scripts/ConnectionManagement/ConnectionState/ClientConnectingState.cs

@@ -13,7 +13,7 @@ namespace Unity.Multiplayer.Samples.BossRoom
     /// entering. If successful, transitions to the ClientConnected state. If not, transitions to the Offline state. If
     /// given a disconnect reason first, transitions to the DisconnectingWithReason state.
     /// </summary>
-    class ClientConnectingState : ConnectionState
+    class ClientConnectingState : OnlineState
     {
         [Inject]
         protected LobbyServiceFacade m_LobbyServiceFacade;
@@ -39,12 +39,6 @@ public override void OnClientDisconnect(ulong _)
             m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
         }
 
-        public override void OnUserRequestedShutdown()
-        {
-            m_ConnectStatusPublisher.Publish(ConnectStatus.UserRequestedDisconnect);
-            m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
-        }
-
         public override void OnDisconnectReasonReceived(ConnectStatus disconnectReason)
         {
             m_ConnectStatusPublisher.Publish(disconnectReason);

Assets/Scripts/ConnectionManagement/ConnectionState/ClientReconnectingState.cs

@@ -59,12 +59,6 @@ public override void OnClientDisconnect(ulong _)
             }
         }
 
-        public override void OnUserRequestedShutdown()
-        {
-            m_ConnectStatusPublisher.Publish(ConnectStatus.UserRequestedDisconnect);
-            m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
-        }
-
         public override void OnDisconnectReasonReceived(ConnectStatus disconnectReason)
         {
             m_ConnectStatusPublisher.Publish(disconnectReason);

Assets/Scripts/ConnectionManagement/ConnectionState/ConnectionState.cs

@@ -7,7 +7,7 @@
 namespace Unity.Multiplayer.Samples.BossRoom
 {
     /// <summary>
-    /// Base class representing a connection state. Contains a static member for each possible state.
+    /// Base class representing a connection state.
     /// </summary>
     abstract class ConnectionState
     {
@@ -39,5 +39,7 @@ public virtual void OnUserRequestedShutdown() { }
         public virtual void OnDisconnectReasonReceived(ConnectStatus disconnectReason) { }
 
         public virtual void ApprovalCheck(NetworkManager.ConnectionApprovalRequest request, NetworkManager.ConnectionApprovalResponse response) { }
+
+        public virtual void OnTransportFailure() { }
     }
 }

Assets/Scripts/ConnectionManagement/ConnectionState/DisconnectingWithReasonState.cs

@@ -5,7 +5,7 @@ namespace Unity.Multiplayer.Samples.BossRoom
     /// Since our disconnect process runs in multiple steps host side, this state is the first step client side. This
     /// state simply waits for the actual disconnect, then transitions to the offline state.
     /// </summary>
-    class DisconnectingWithReasonState : ConnectionState
+    class DisconnectingWithReasonState : OnlineState
     {
         public override void Enter() { }
 
@@ -15,10 +15,5 @@ public override void OnClientDisconnect(ulong _)
         {
             m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
         }
-
-        public override void OnUserRequestedShutdown()
-        {
-            m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
-        }
     }
 }

Assets/Scripts/ConnectionManagement/ConnectionState/HostingState.cs

@@ -13,7 +13,7 @@ namespace Unity.Multiplayer.Samples.BossRoom
     /// Connection state corresponding to a listening host. Handles incoming client connections. When shutting down or
     /// being timed out, transitions to the Offline state.
     /// </summary>
-    class HostingState : ConnectionState
+    class HostingState : OnlineState
     {
         [Inject]
         LobbyServiceFacade m_LobbyServiceFacade;

Assets/Scripts/ConnectionManagement/ConnectionState/OnlineState.cs

@@ -0,0 +1,22 @@
+namespace Unity.Multiplayer.Samples.BossRoom
+{
+    /// <summary>
+    /// Base class representing an online connection state.
+    /// </summary>
+    abstract class OnlineState : ConnectionState
+    {
+
+        public override void OnUserRequestedShutdown()
+        {
+            // This behaviour will be the same for every online state
+            m_ConnectStatusPublisher.Publish(ConnectStatus.UserRequestedDisconnect);
+            m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
+        }
+
+        public override void OnTransportFailure()
+        {
+            // This behaviour will be the same for every online state
+            m_ConnectionManager.ChangeState(m_ConnectionManager.m_Offline);
+        }
+    }
+}

Assets/Scripts/ConnectionManagement/ConnectionState/StartingHostState.cs

@@ -11,7 +11,7 @@ namespace Unity.Multiplayer.Samples.BossRoom
     /// Connection state corresponding to a host starting up. Starts the host when entering the state. If successful,
     /// transitions to the Hosting state, if not, transitions back to the Offline state.
     /// </summary>
-    class StartingHostState : ConnectionState
+    class StartingHostState : OnlineState
     {
         [Inject]
         LobbyServiceFacade m_LobbyServiceFacade;

CHANGELOG.md

@@ -9,8 +9,9 @@ Additional documentation and release notes are available at [Multiplayer Documen
 ## [Unreleased] - yyyy-mm-dd
 
 ### Added
+* Added handling the OnTransportFailure callback (#707). This callback is invoked when a failure happens on the transport's side, for example if the host loses connection to the Relay service. This won't get called when the host is just listening with direct IP, this would need to be handled differently (by pinging an external service like google to test for internet connectivity for example). Boss Room now handles that callback by returning to the Offline state.
 * Pickup and Drop action added to the Action system. Actionable once targeting a "Heavy"-tagged NetworkObject. (#372) - This shows NetworkObject parenting with a pattern to follow animation bones (the hands when picking up)
-
+*
 ### Changed
 * Updated tools, authentication and relay packages (#690)
 * Replaced our dependency injection solution with VContainer. (#679)