Update callback is now void (or async void)

Added ListenUpdates example

Examples/Program_ListenUpdates.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using TL;
+
+namespace WTelegramClientTest
+{
+	class Program_ListenUpdates
+	{
+		static string Config(string what)
+		{
+			// go to Project Properties > Debug > Environment variables and add at least these: api_id, api_hash, phone_number
+			if (what == "verification_code") { Console.Write("Code: "); return Console.ReadLine(); }
+			return Environment.GetEnvironmentVariable(what);
+		}
+
+		static async Task Main(string[] _)
+		{
+			Console.WriteLine("The program will display updates received for the logged-in user. Press any key to terminate");
+			WTelegram.Helpers.Log += (l, s) => System.Diagnostics.Debug.WriteLine(s);
+			using var client = new WTelegram.Client(Config);// { CollectAccessHash = true };
+			client.Update += Client_Update;
+			await client.ConnectAsync();
+			var user = await client.LoginUserIfNeeded();
+			// note that on logging, Telegram may sends a bunch of updates/messages that happened in the past and were not acknowledged
+			Console.WriteLine($"We are logged-in as {user.username ?? user.first_name + " " + user.last_name} (id {user.id})");
+			await client.Ping(42); // dummy API call.. this is used to force an acknowledge on past updates
+			Console.ReadKey();
+			await client.Ping(43); // dummy API call.. this is used to force an acknowledge on this session's updates
+		}
+
+
+		private static readonly Dictionary<int, UserBase> users = new();
+		private static readonly Dictionary<int, ChatBase> chats = new();
+		private static string AUser(int user_id) => users.TryGetValue(user_id, out var user) ? user.DisplayName : $"User {user_id}";
+		private static string AChat(int chat_id) => chats.TryGetValue(chat_id, out var chat) ? chat.Title : $"Chat {chat_id}";
+		private static string APeer(Peer peer) => peer is null ? null : peer is PeerUser user ? AUser(user.user_id)
+			: peer is PeerChat chat ? AChat(chat.chat_id) : peer is PeerChannel channel ? AChat(channel.channel_id) : $"Peer {peer.ID}";
+
+		private static void Client_Update(ITLObject arg)
+		{
+			switch (arg)
+			{
+				case UpdateShortMessage usm: Console.WriteLine($"{AUser(usm.user_id)}> {usm.message}"); break;
+				case UpdateShortChatMessage uscm: Console.WriteLine($"{AUser(uscm.from_id)} in {AChat(uscm.chat_id)}> {uscm.message}"); break;
+				case UpdateShortSentMessage: Console.WriteLine($"You sent a message"); break;
+				case UpdateShort updateShort: DisplayUpdate(updateShort.update); break;
+				case Updates u:
+					foreach (var user in u.users) users[user.ID] = user;
+					foreach (var chat in u.chats) chats[chat.ID] = chat;
+					foreach (var update in u.updates) DisplayUpdate(update);
+					break;
+				case UpdatesCombined uc:
+					foreach (var user in uc.users) users[user.ID] = user;
+					foreach (var chat in uc.chats) chats[chat.ID] = chat;
+					foreach (var update in uc.updates) DisplayUpdate(update);
+					break;
+				default: Console.WriteLine(arg.GetType().Name); break;
+			}
+		}
+
+		private static void DisplayUpdate(Update update)
+		{
+			switch (update)
+			{
+				case UpdateNewMessage unm: DisplayMessage(unm.message); break;
+				case UpdateEditMessage uem: Console.Write("(Edit): "); DisplayMessage(uem.message); break;
+				case UpdateDeleteMessages udm: Console.WriteLine($"{udm.messages.Length} message(s) deleted"); break;
+				case UpdateNewChannelMessage uncm: DisplayMessage(uncm.message); break;
+				case UpdateEditChannelMessage uecm: Console.Write("(Edit): "); DisplayMessage(uecm.message); break;
+				case UpdateDeleteChannelMessages udcm: Console.WriteLine($"{udcm.messages.Length} message(s) deleted in {AChat(udcm.channel_id)}"); break;
+				case UpdateUserTyping uut: Console.WriteLine($"{AUser(uut.user_id)} is {uut.action.GetType().Name[11..^6]}"); break;
+				case UpdateChatUserTyping ucut: Console.WriteLine($"{APeer(ucut.from_id)} is {ucut.action.GetType().Name[11..^6]} in {AChat(ucut.chat_id)}"); break;
+				case UpdateChannelUserTyping ucut2: Console.WriteLine($"{APeer(ucut2.from_id)} is {ucut2.action.GetType().Name[11..^6]} in {AChat(ucut2.channel_id)}"); break;
+				case UpdateChatParticipants { participants: ChatParticipants cp }: Console.WriteLine($"{cp.participants.Length} participants in {AChat(cp.chat_id)}"); break;
+				case UpdateUserStatus uus: Console.WriteLine($"{AUser(uus.user_id)} is now {uus.status.GetType().Name[10..]}"); break;
+				case UpdateUserName uun: Console.WriteLine($"{AUser(uun.user_id)} has changed profile name: @{uun.username} {uun.first_name} {uun.last_name}"); break;
+				case UpdateUserPhoto uup: Console.WriteLine($"{AUser(uup.user_id)} has changed profile photo"); break;
+				default: Console.WriteLine(update.GetType().Name); break;
+			}
+		}
+
+		private static void DisplayMessage(MessageBase messageBase)
+		{
+			switch (messageBase)
+			{
+				case Message m: Console.WriteLine($"{APeer(m.from_id) ?? m.post_author} in {APeer(m.peer_id)}> {m.message}"); break;
+				case MessageService ms: Console.WriteLine($"{APeer(ms.from_id)} in {APeer(ms.peer_id)} [{ms.action.GetType().Name[13..]}]"); break;
+			}
+		}
+	}
+}

src/Client.cs

@@ -19,8 +19,9 @@ namespace WTelegram
 {
 	public sealed partial class Client : IDisposable
 	{
-		public event Func<ITLObject, Task> Update;
+		public event Action<ITLObject> Update;
 		public Config TLConfig { get; private set; }
+
 		private readonly Func<string, string> _config;
 		private readonly int _apiId;
 		private readonly string _apiHash;
@@ -49,8 +50,6 @@ namespace WTelegram
 			_session = Session.LoadOrCreate(Config("session_pathname"), Convert.FromHexString(_apiHash));
 		}
 
-		private Task OnUpdate(ITLObject obj) => Update?.Invoke(obj) ?? Task.CompletedTask;
-
 		public string Config(string config)
 			=> _config(config) ?? DefaultConfig(config) ?? throw new ApplicationException("You must provide a config value for " + config);
 
@@ -597,10 +596,10 @@ namespace WTelegram
 					_ = SendAsync(MakeFunction(new Pong { msg_id = _lastRecvMsgId, ping_id = ping.ping_id }), false);
 					break;
 				case Pong pong:
-					await SetResult(pong.msg_id, pong);
+					SetResult(pong.msg_id, pong);
 					break;
 				case FutureSalts futureSalts:
-					await SetResult(futureSalts.req_msg_id, futureSalts);
+					SetResult(futureSalts.req_msg_id, futureSalts);
 					break;
 				case RpcResult rpcResult:
 					break; // SetResult was already done in ReadRpcResult
@@ -616,7 +615,7 @@ namespace WTelegram
 							_ = Task.Run(() => tcs.SetException(new ApplicationException($"BadMsgNotification {badMsgNotification.error_code}")));
 						}
 						else
-							await OnUpdate(obj);
+							OnUpdate(obj);
 					}
 					break;
 				default:
@@ -627,19 +626,32 @@ namespace WTelegram
 						{
 							_bareRequest = 0;
 							_ = Task.Run(() => tcs.SetResult(obj));
+							break;
 						}
 					}
-					await OnUpdate(obj);
+					OnUpdate(obj);
 					break;
 			}
 
-			async Task SetResult(long msgId, object result)
+			void SetResult(long msgId, object result)
 			{
 				var (type, tcs) = PullPendingRequest(msgId);
 				if (tcs != null)
 					_ = Task.Run(() => tcs.SetResult(result));
 				else
-					await OnUpdate(obj);
+					OnUpdate(obj);
+			}
+		}
+
+		private void OnUpdate(ITLObject obj)
+		{
+			try
+			{
+				Update?.Invoke(obj);
+			}
+			catch (Exception ex)
+			{
+				Helpers.Log(4, $"Update callback on {obj.GetType().Name} raised {ex}");
 			}
 		}
 
@@ -721,7 +733,7 @@ namespace WTelegram
 			{
 				var waitUntil = DateTime.UtcNow.AddSeconds(3);
 				if (signUpRequired.terms_of_service != null)
-					await OnUpdate(signUpRequired.terms_of_service); // give caller the possibility to read and accept TOS
+					OnUpdate(signUpRequired.terms_of_service); // give caller the possibility to read and accept TOS
 				var first_name = Config("first_name");
 				var last_name = Config("last_name");
 				var wait = waitUntil - DateTime.UtcNow;

src/WTelegramClient.csproj

@@ -38,6 +38,7 @@
     <None Include="..\logo.png" Link="Data\logo.png" Pack="true" PackagePath="\" />
     <None Include="..\README.md" Link="Data\README.md" Pack="true" PackagePath="\" />
     <None Include="..\.github\release.yml" Link="Data\release.yml" />
+    <None Include="..\Examples\*.cs" Link="Data\Examples\%(RecursiveDir)%(Filename)%(Extension)" />
   </ItemGroup>
 
   <ItemGroup>