Merge 2041e475dd into 97397f3617

src/Discord.Net.Core/Net/FatalException.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace Discord.Net
+{
+    public class FatalException : Exception
+    {
+        public FatalException(string reason, Exception inner)
+            : base(reason, inner)
+        {
+        }
+    }
+}

src/Discord.Net.Core/Net/WebSocketClosedException.cs

@@ -1,4 +1,5 @@
-using System;
+using System;
+
 namespace Discord.Net
 {
     public class WebSocketClosedException : Exception

src/Discord.Net.WebSocket/Audio/AudioClient.cs

@@ -1,4 +1,4 @@
-using Discord.API.Voice;
+using Discord.API.Voice;
 using Discord.Audio.Streams;
 using Discord.Logging;
 using Discord.Net.Converters;
@@ -71,7 +71,7 @@ namespace Discord.Audio
             ApiClient.ReceivedPacket += ProcessPacketAsync;
 
             _stateLock = new SemaphoreSlim(1, 1);
-            _connection = new ConnectionManager(_stateLock, _audioLogger, 30000, 
+            _connection = new ConnectionManager(_stateLock, _audioLogger, 30000, false,
                 OnConnectingAsync, OnDisconnectingAsync, x => ApiClient.Disconnected += x);
             _connection.Connected += () => _connectedEvent.InvokeAsync();
             _connection.Disconnected += (ex, recon) => _disconnectedEvent.InvokeAsync(ex);

src/Discord.Net.WebSocket/ConnectionManager.cs

@@ -1,13 +1,17 @@
 using Discord.Logging;
+using Discord.Net;
 using System;
 using System.Threading;
 using System.Threading.Tasks;
-using Discord.Net;
+using System.Linq;
 
 namespace Discord
 {
     internal class ConnectionManager
     {
+        // close codes that cannot be recovered from
+        private static readonly int[] _fatalErrorCodes = { 4004, 4010, 4011 };
+
         public event Func<Task> Connected { add { _connectedEvent.Add(value); } remove { _connectedEvent.Remove(value); } }
         private readonly AsyncEvent<Func<Task>> _connectedEvent = new AsyncEvent<Func<Task>>();
         public event Func<Exception, bool, Task> Disconnected { add { _disconnectedEvent.Add(value); } remove { _disconnectedEvent.Remove(value); } }
@@ -26,7 +30,7 @@ namespace Discord
         public ConnectionState State { get; private set; }
         public CancellationToken CancelToken { get; private set; }
 
-        internal ConnectionManager(SemaphoreSlim stateLock, Logger logger, int connectionTimeout, 
+        internal ConnectionManager(SemaphoreSlim stateLock, Logger logger, int connectionTimeout, bool invalidStateFatal,
             Func<Task> onConnecting, Func<Exception, Task> onDisconnecting, Action<Func<Exception, Task>> clientDisconnectHandler)
         {
             _stateLock = stateLock;
@@ -40,8 +44,8 @@ namespace Discord
                 if (ex != null)
                 {
                     var ex2 = ex as WebSocketClosedException;
-                    if (ex2?.CloseCode == 4006)
-                        CriticalError(new Exception("WebSocket session expired", ex));
+                    if ((invalidStateFatal && ex2?.CloseCode == 4006) || _fatalErrorCodes.Contains(ex2?.CloseCode ?? 0))
+                        FatalError(new FatalException("WebSocket connection was closed with an unrecoverable error", ex));
                     else
                         Error(new Exception("WebSocket connection was closed", ex));
                 }
@@ -186,7 +190,7 @@ namespace Discord
             _connectionPromise.TrySetException(ex);
             _connectionCancelToken?.Cancel();
         }
-        public void CriticalError(Exception ex)
+        public void FatalError(Exception ex)
         {
             _reconnectCancelToken?.Cancel();
             Error(ex);
@@ -207,4 +211,4 @@ namespace Discord
             }
         }
     }
-}
+}

src/Discord.Net.WebSocket/DiscordSocketApiClient.cs

@@ -1,4 +1,4 @@
-#pragma warning disable CS1591
+#pragma warning disable CS1591
 using Discord.API.Gateway;
 using Discord.API.Rest;
 using Discord.Net.Queue;

src/Discord.Net.WebSocket/DiscordSocketClient.cs

@@ -90,7 +90,7 @@ namespace Discord.WebSocket
 
             _stateLock = new SemaphoreSlim(1, 1);
             _gatewayLogger = LogManager.CreateLogger(ShardId == 0 && TotalShards == 1 ? "Gateway" : $"Shard #{ShardId}");
-            _connection = new ConnectionManager(_stateLock, _gatewayLogger, config.ConnectionTimeout, 
+            _connection = new ConnectionManager(_stateLock, _gatewayLogger, config.ConnectionTimeout, config.InvalidStateFatal,
                 OnConnectingAsync, OnDisconnectingAsync, x => ApiClient.Disconnected += x);
             _connection.Connected += () => TimedInvokeAsync(_connectedEvent, nameof(Connected));
             _connection.Disconnected += (ex, recon) => TimedInvokeAsync(_disconnectedEvent, nameof(Disconnected), ex);
@@ -466,7 +466,7 @@ namespace Discord.WebSocket
                                     }
                                     catch (Exception ex)
                                     {
-                                        _connection.CriticalError(new Exception("Processing READY failed", ex));
+                                        _connection.FatalError(new Exception("Processing READY failed", ex));
                                         return;
                                     }
 

src/Discord.Net.WebSocket/DiscordSocketConfig.cs

@@ -1,4 +1,4 @@
-using Discord.Net.Udp;
+using Discord.Net.Udp;
 using Discord.Net.WebSockets;
 using Discord.Rest;
 
@@ -25,6 +25,10 @@ namespace Discord.WebSocket
         /// Gets or sets the max number of users a guild may have for offline users to be included in the READY packet. Max is 250.
         /// </summary>
         public int LargeThreshold { get; set; } = 250;
+        /// <summary>
+        /// Gets or sets whether a State Invalidation from Discord should be fatal. Setting this to false could lead to unexpected behavior when Discord is unstable.
+        /// </summary>
+        public bool InvalidStateFatal { get; set; } = true;
 
         /// <summary> Gets or sets the provider used to generate new websocket connections. </summary>
         public WebSocketProvider WebSocketProvider { get; set; }