fix: scene change race condition. wait for server to be ready (#339)

* fix: scene change race condition. wait for server to be ready * add tests
MirageNet · Aug 24, 2020 · 2ca0340 · 2ca0340
1 parent b4ec01a
commit 2ca0340
Show file tree

Hide file tree

Showing 3 changed files with 52 additions and 1 deletion.
diff --git a/Assets/Mirror/Runtime/Messages.cs b/Assets/Mirror/Runtime/Messages.cs
@@ -61,6 +61,13 @@ public void Serialize(NetworkWriter writer)
         }
     }
 
+    public struct SceneReadyMessage : IMessageBase
+    {
+        public void Deserialize(NetworkReader reader) { /* nothing to serialize */ }
+
+        public void Serialize(NetworkWriter writer) { /* nothing to serialize */ }
+    }
+
     public enum SceneOperation : byte
     {
         Normal,

diff --git a/Assets/Mirror/Runtime/NetworkSceneManager.cs b/Assets/Mirror/Runtime/NetworkSceneManager.cs
@@ -54,6 +54,8 @@ public class NetworkSceneManager : MonoBehaviour, INetworkSceneManager
         /// </remarks>
         public string NetworkSceneName { get; protected set; } = "";
 
+        internal AsyncOperation asyncOperation;
+
         public void Start()
         {
             DontDestroyOnLoad(gameObject);
@@ -77,6 +79,7 @@ void RegisterClientMessages(INetworkConnection connection)
         {
             connection.RegisterHandler<NotReadyMessage>(ClientNotReadyMessage);
             connection.RegisterHandler<SceneMessage>(ClientSceneMessage);
+            connection.RegisterHandler<SceneReadyMessage>(ClientSceneReadyMessage);
         }
 
         // called after successful authentication
@@ -120,6 +123,13 @@ internal void ClientSceneMessage(INetworkConnection conn, SceneMessage msg)
             StartCoroutine(ApplySceneOperation(msg.sceneName, msg.sceneOperation));
         }
 
+        internal void ClientSceneReadyMessage(INetworkConnection conn, SceneReadyMessage msg)
+        {
+            logger.Log("ClientSceneReadyMessage");
+
+            asyncOperation.allowSceneActivation = true;
+        }
+
         internal void ClientNotReadyMessage(INetworkConnection conn, NotReadyMessage msg)
         {
             logger.Log("NetworkSceneManager.OnClientNotReadyMessageInternal");
@@ -244,6 +254,8 @@ internal void OnServerChangeScene(string newSceneName, SceneOperation operation)
         /// <param name="sceneName">The name of the new scene.</param>
         internal void OnServerSceneChanged(string sceneName, SceneOperation operation)
         {
+            server.SendToAll(new SceneReadyMessage());
+
             ServerSceneChanged.Invoke(sceneName, operation);
         }
 
@@ -255,7 +267,15 @@ IEnumerator ApplySceneOperation(string sceneName, SceneOperation sceneOperation
             {
                 case SceneOperation.Normal:
                     NetworkSceneName = sceneName;
-                    yield return SceneManager.LoadSceneAsync(sceneName);
+                    asyncOperation = SceneManager.LoadSceneAsync(sceneName);
+
+                    //If non host client. Wait for server to finish scene change
+                    if(client && client.Active && !client.IsLocalClient)
+                    {
+                        asyncOperation.allowSceneActivation = false;
+                    }
+
+                    yield return asyncOperation;
                     break;
                 case SceneOperation.LoadAdditive:
                     // Ensure additive scene is not already loaded since we don't know which was passed in the Scene message

diff --git a/Assets/Mirror/Tests/Runtime/NetworkSceneManagerTests.cs b/Assets/Mirror/Tests/Runtime/NetworkSceneManagerTests.cs
@@ -248,5 +248,29 @@ public void NetworkSceneNameStringEmptyTest()
         {
             Assert.That(clientSceneManager.NetworkSceneName.Equals(string.Empty));
         }
+
+        [Test]
+        public void AsyncOperationInitStateTest()
+        {
+            Assert.That(clientSceneManager.asyncOperation, Is.Null);
+        }
+
+        [Test]
+        public void AsyncOperationStateTest()
+        {
+            clientSceneManager.ClientSceneMessage(null, new SceneMessage { sceneName = "testScene" });
+
+            Assert.That(clientSceneManager.asyncOperation, Is.Not.Null);
+            Assert.That(clientSceneManager.asyncOperation.allowSceneActivation, Is.False);
+        }
+
+        [Test]
+        public void ClientSceneReadyMessageTest()
+        {
+            clientSceneManager.ClientSceneMessage(null, new SceneMessage { sceneName = "testScene" });
+            clientSceneManager.ClientSceneReadyMessage(null, new SceneReadyMessage());
+
+            Assert.That(clientSceneManager.asyncOperation.allowSceneActivation, Is.True);
+        }
     }
 }