fix(NetworkAuthenticator): Unity 2019 Compatibility

Author: MrGadget1024

Assets/Mirror/Authenticators/UniqueNameAuthenticator.cs

@@ -7,6 +7,12 @@
 
 namespace Mirror.Authenticators
 {
+#if !UNITY_2020_3_OR_NEWER
+    /// <summary>UnityEvent subclass for notifying when a client is authenticated on the server</summary>
+    [Serializable]
+    public class StringEvent : UnityEvent<string> { }
+#endif
+
     public class UniqueNameAuthenticator : NetworkAuthenticator
     {
         readonly HashSet<NetworkConnectionToClient> connectionsPendingDisconnect = new HashSet<NetworkConnectionToClient>();
@@ -16,8 +22,14 @@ public class UniqueNameAuthenticator : NetworkAuthenticator
         public string playerName;
 
         [Header("Events")]
+#if !UNITY_2020_3_OR_NEWER
+        // Unity 2019 compatibility
+        public StringEvent OnAuthSuccess = new StringEvent();
+        public StringEvent OnAuthFailure = new StringEvent();
+#else
         public UnityEvent<string> OnAuthSuccess = new UnityEvent<string>();
         public UnityEvent<string> OnAuthFailure = new UnityEvent<string>();
+#endif
 
         #region Messages
 

Assets/Mirror/Core/NetworkAuthenticator.cs

@@ -4,14 +4,25 @@
 
 namespace Mirror
 {
+#if !UNITY_2020_3_OR_NEWER
+    /// <summary>UnityEvent subclass for notifying when a client is authenticated on the server</summary>
+    [Serializable]
+    public class NetworkConnectionToClientEvent : UnityEvent<NetworkConnectionToClient> { }
+#endif
+
     /// <summary>Base class for implementing component-based authentication during the Connect phase</summary>
     [HelpURL("https://mirror-networking.gitbook.io/docs/components/network-authenticators")]
     public abstract class NetworkAuthenticator : MonoBehaviour
     {
         /// <summary>Notify subscribers on the server when a client is authenticated</summary>
         [Header("Event Listeners (optional)")]
         [Tooltip("Mirror has an internal subscriber to this event. You can add your own here.")]
+#if !UNITY_2020_3_OR_NEWER
+        // Unity 2019 compatibility
+        public NetworkConnectionToClientEvent OnServerAuthenticated = new NetworkConnectionToClientEvent();
+#else
         public UnityEvent<NetworkConnectionToClient> OnServerAuthenticated = new UnityEvent<NetworkConnectionToClient>();
+#endif
 
         /// <summary>Notify subscribers on the client when the client is authenticated</summary>
         [Tooltip("Mirror has an internal subscriber to this event. You can add your own here.")]