fixed youtube stream notifications incase invalid channel was provided

src/EllieBot/Modules/Searches/_common/StreamNotifications/NotifChecker.cs

@@ -63,20 +63,19 @@ public class NotifChecker
                                 .ToDictionary(x => x.Key.Name, x => x.Value));
 
                     var newStreamData = await oldStreamDataDict
-                        .Select(x =>
+                        .Select(async x =>
                         {
                             // get all stream data for the streams of this type
                             if (_streamProviders.TryGetValue(x.Key,
                                     out var provider))
                             {
-                                return provider.GetStreamDataAsync(x.Value
+                                return await provider.GetStreamDataAsync(x.Value
                                     .Select(entry => entry.Key)
                                     .ToList());
                             }
 
                             // this means there's no provider for this stream data, (and there was before?)
-                            return Task.FromResult<IReadOnlyCollection<StreamData>>(
-                                new List<StreamData>());
+                            return [];
                         })
                         .WhenAll();
 

src/EllieBot/Modules/Searches/_common/StreamNotifications/Providers/YouTubeProvider.cs

@@ -1,12 +1,7 @@
-using System.Net;
-using EllieBot.Db.Models;
-using EllieBot.Services;
+using EllieBot.Db.Models;
 using System.Text.RegularExpressions;
 using System.Net.Http.Json;
-using System.Text.Json;
 using System.Text.Json.Serialization;
-using System.Xml.Linq;
-using AngleSharp.Browser;
 
 namespace EllieBot.Modules.Searches.Common.StreamNotifications.Providers;
 
@@ -112,6 +107,8 @@ public sealed partial class YouTubeProvider : Provider
     /// <param name="channelId">Channel ID or name</param>
     /// <returns><see cref="StreamData"/> of the channel. Null if none found</returns>
     public override async Task<StreamData?> GetStreamDataAsync(string channelId)
+    {
+        try
         {
             var instances = _scs.Data.InvidiousInstances;
 
@@ -164,6 +161,13 @@ public sealed partial class YouTubeProvider : Provider
                 UniqueName = vid.AuthorId,
             };
         }
+        catch (Exception ex)
+        {
+            Log.Warning(ex, "Unable to get stream data for a youtube channel {ChannelId}", channelId);
+            _failingStreams.TryAdd(channelId, DateTime.UtcNow);
+            return null;
+        }
+    }
 
     /// <summary>
     /// Gets stream data of all specified YouTube channels