fix(Discovery): Updated Network Discovery

- Moved transport and OnServerFound to base class
- Consolidated Start in base class
- Virtual OnValidate in base class
- Better public field order
- Added missing tooltip

Assets/Mirror/Components/Discovery/NetworkDiscovery.cs

@@ -14,27 +14,6 @@ public class NetworkDiscovery : NetworkDiscoveryBase<ServerRequest, ServerRespon
     {
         #region Server
 
-        public long ServerId { get; private set; }
-
-        [Tooltip("Transport to be advertised during discovery")]
-        public Transport transport;
-
-        [Tooltip("Invoked when a server is found")]
-        public ServerFoundUnityEvent OnServerFound;
-
-        public override void Start()
-        {
-            ServerId = RandomLong();
-
-            // active transport gets initialized in awake
-            // so make sure we set it here in Start()  (after awakes)
-            // Or just let the user assign it in the inspector
-            if (transport == null)
-                transport = Transport.active;
-
-            base.Start();
-        }
-
         /// <summary>
         /// Process the request from a client
         /// </summary>
@@ -68,9 +47,11 @@ protected override ServerResponse ProcessRequest(ServerRequest request, IPEndPoi
                 throw;
             }
         }
+
         #endregion
 
         #region Client
+
         /// <summary>
         /// Create a message that will be broadcasted on the network to discover servers
         /// </summary>
@@ -106,6 +87,7 @@ protected override void ProcessResponse(ServerResponse response, IPEndPoint endp
 
             OnServerFound.Invoke(response);
         }
+
         #endregion
     }
 }

Assets/Mirror/Components/Discovery/NetworkDiscoveryBase.cs

@@ -23,33 +23,46 @@ public abstract class NetworkDiscoveryBase<Request, Response> : MonoBehaviour
     {
         public static bool SupportedOnThisPlatform { get { return Application.platform != RuntimePlatform.WebGLPlayer; } }
 
-        // each game should have a random unique handshake,  this way you can tell if this is the same game or not
-        [HideInInspector]
-        public long secretHandshake;
+        [SerializeField]
+        [Tooltip("If true, broadcasts a discovery request every ActiveDiscoveryInterval seconds")]
+        public bool enableActiveDiscovery = true;
+
+        // broadcast address needs to be configurable on iOS:
+        // https://github.com/vis2k/Mirror/pull/3255
+        [Tooltip("iOS may require LAN IP address here (e.g. 192.168.x.x), otherwise leave blank.")]
+        public string BroadcastAddress = "";
 
         [SerializeField]
         [Tooltip("The UDP port the server will listen for multi-cast messages")]
         protected int serverBroadcastListenPort = 47777;
 
-        [SerializeField]
-        [Tooltip("If true, broadcasts a discovery request every ActiveDiscoveryInterval seconds")]
-        public bool enableActiveDiscovery = true;
-
         [SerializeField]
         [Tooltip("Time in seconds between multi-cast messages")]
         [Range(1, 60)]
         float ActiveDiscoveryInterval = 3;
         
-        // broadcast address needs to be configurable on iOS:
-        // https://github.com/vis2k/Mirror/pull/3255
-        public string BroadcastAddress = "";
+        [Tooltip("Transport to be advertised during discovery")]
+        public Transport transport;
+
+        [Tooltip("Invoked when a server is found")]
+        public ServerFoundUnityEvent OnServerFound;
+
+        // Each game should have a random unique handshake,
+        // this way you can tell if this is the same game or not
+        [HideInInspector]
+        public long secretHandshake;
+
+        public long ServerId { get; private set; }
 
         protected UdpClient serverUdpClient;
         protected UdpClient clientUdpClient;
 
 #if UNITY_EDITOR
-        void OnValidate()
+        public virtual void OnValidate()
         {
+            if (transport == null)
+                transport = GetComponent<Transport>();
+
             if (secretHandshake == 0)
             {
                 secretHandshake = RandomLong();
@@ -58,24 +71,32 @@ void OnValidate()
         }
 #endif
 
-        public static long RandomLong()
-        {
-            int value1 = UnityEngine.Random.Range(int.MinValue, int.MaxValue);
-            int value2 = UnityEngine.Random.Range(int.MinValue, int.MaxValue);
-            return value1 + ((long)value2 << 32);
-        }
-
         /// <summary>
         /// virtual so that inheriting classes' Start() can call base.Start() too
         /// </summary>
         public virtual void Start()
         {
+            ServerId = RandomLong();
+
+            // active transport gets initialized in Awake
+            // so make sure we set it here in Start() after Awake
+            // Or just let the user assign it in the inspector
+            if (transport == null)
+                transport = Transport.active;
+
             // Server mode? then start advertising
 #if UNITY_SERVER
             AdvertiseServer();
 #endif
         }
 
+        public static long RandomLong()
+        {
+            int value1 = UnityEngine.Random.Range(int.MinValue, int.MaxValue);
+            int value2 = UnityEngine.Random.Range(int.MinValue, int.MaxValue);
+            return value1 + ((long)value2 << 32);
+        }
+
         // Ensure the ports are cleared no matter when Game/Unity UI exits
         void OnApplicationQuit()
         {
@@ -166,9 +187,7 @@ public async Task ServerListenAsync()
                     // socket has been closed
                     break;
                 }
-                catch (Exception)
-                {
-                }
+                catch (Exception) {}
             }
         }
 
@@ -247,6 +266,7 @@ protected virtual void ProcessClientRequest(Request request, IPEndPoint endpoint
         AndroidJavaObject multicastLock;
         bool hasMulticastLock;
 #endif
+
         void BeginMulticastLock()
 		{
 #if UNITY_ANDROID