Adds a Discord reconnection test

src/Tgstation.Server.Host/Components/Chat/Providers/IProvider.cs

@@ -25,7 +25,7 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// </summary>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation</param>
 		/// <returns>A <see cref="Task{TResult}"/> resulting in the next available <see cref="Message"/> or <see langword="null"/> if the <see cref="IProvider"/> needed to reconnect.</returns>
-		/// <remarks>Note that private messages will come in the form of <see cref="Channel"/>s not returned in <see cref="MapChannels(IEnumerable{Api.Models.ChatChannel}, CancellationToken)"/></remarks>
+		/// <remarks>Note that private messages will come in the form of <see cref="Channel"/>s not returned in <see cref="MapChannels(IEnumerable{Api.Models.ChatChannel}, CancellationToken)"/>. Do not <see cref="IDisposable.Dispose"/> the <see cref="IProvider"/> on continuations run from the returned <see cref="Task"/>.</remarks>
 		Task<Message> NextMessage(CancellationToken cancellationToken);
 
 		/// <summary>

src/Tgstation.Server.Host/Components/Chat/Providers/Provider.cs

@@ -20,6 +20,11 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// </summary>
 		readonly Queue<Message> messageQueue;
 
+		/// <summary>
+		/// Used for synchronizing access to <see cref="reconnectCts"/> and <see cref="reconnectTask"/>.
+		/// </summary>
+		readonly object reconnectTaskLock;
+
 		/// <summary>
 		/// <see cref="TaskCompletionSource{TResult}"/> that completes while <see cref="messageQueue"/> isn't empty
 		/// </summary>
@@ -47,6 +52,8 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 			messageQueue = new Queue<Message>();
 			nextMessage = new TaskCompletionSource<object>();
 
+			reconnectTaskLock = new object();
+
 			SetReconnectInterval(reconnectInterval).GetAwaiter().GetResult();
 			logger.LogTrace("Created.");
 		}
@@ -106,35 +113,37 @@ namespace Tgstation.Server.Host.Components.Chat.Providers
 		/// Stops and awaits the <see cref="reconnectTask"/>.
 		/// </summary>
 		/// <returns>A <see cref="Task"/> representing the running operation.</returns>
-		async Task StopReconnectionTimer()
+		Task StopReconnectionTimer()
 		{
-			reconnectCts?.Cancel();
-			reconnectCts?.Dispose();
-			if (reconnectTask != null)
-			{
-				await reconnectTask.ConfigureAwait(false);
-				reconnectTask = null;
-			}
+			lock (reconnectTaskLock)
+				if (reconnectCts != null)
+				{
+					reconnectCts.Cancel();
+					reconnectCts.Dispose();
+					reconnectCts = null;
+					Task reconnectTask = this.reconnectTask;
+					this.reconnectTask = null;
+					return reconnectTask;
+				}
+
+			return Task.CompletedTask;
 		}
 
 		/// <inheritdoc />
-		public async Task SetReconnectInterval(uint reconnectInterval)
+		public Task SetReconnectInterval(uint reconnectInterval)
 		{
 			if (reconnectInterval == 0)
 				throw new ArgumentOutOfRangeException(nameof(reconnectInterval), reconnectInterval, "Reconnect interval cannot be zero!");
 
-			await StopReconnectionTimer().ConfigureAwait(false);
-			reconnectCts = new CancellationTokenSource();
-			try
+			Task stopOldTimerTask;
+			lock (reconnectTaskLock)
 			{
+				stopOldTimerTask = StopReconnectionTimer();
+				reconnectCts = new CancellationTokenSource();
 				reconnectTask = ReconnectionLoop(reconnectInterval, reconnectCts.Token);
 			}
-			catch
-			{
-				reconnectCts.Dispose();
-				reconnectCts = null;
-				throw;
-			}
+
+			return stopOldTimerTask;
 		}
 
 		/// <summary>

src/Tgstation.Server.Host/Properties/AssemblyInfo.cs

@@ -1,4 +1,5 @@
 using System.Runtime.CompilerServices;
 
 [assembly: InternalsVisibleTo("Tgstation.Server.Host.Tests")]
+[assembly: InternalsVisibleTo("Tgstation.Server.Tests")]
 [assembly: InternalsVisibleTo("DynamicProxyGenAssembly2")]

tests/Tgstation.Server.Tests/IntegrationTest.cs

@@ -1,8 +1,10 @@
+using Discord.WebSocket;
+using Microsoft.Extensions.Logging;
 using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Moq;
 using System;
 using System.Diagnostics;
 using System.IO;
-using System.Linq;
 using System.Net.Http.Headers;
 using System.Reflection;
 using System.Threading;
@@ -11,16 +13,67 @@ using Tgstation.Server.Api;
 using Tgstation.Server.Api.Models;
 using Tgstation.Server.Client;
 using Tgstation.Server.Host;
+using Tgstation.Server.Host.Components.Chat.Providers;
 
 namespace Tgstation.Server.Tests
 {
 	[TestClass]
+	[TestCategory("SkipWhenLiveUnitTesting")]
 	public sealed class IntegrationTest
 	{
 		readonly IServerClientFactory clientFactory = new ServerClientFactory(new ProductHeaderValue(Assembly.GetExecutingAssembly().GetName().Name, Assembly.GetExecutingAssembly().GetName().Version.ToString()));
-		
+
+		[TestMethod]
+		public async Task TestAutomaticDiscordReconnection()
+		{
+			var discordToken = Environment.GetEnvironmentVariable("TGS4_TEST_DISCORD_TOKEN");
+			if (String.IsNullOrWhiteSpace(discordToken))
+				Assert.Inconclusive("The TGS4_TEST_DISCORD_TOKEN environment variable must be set to run this test!");
+
+			using (var discordProvider = new DiscordProvider(Mock.Of<ILogger<DiscordProvider>>(), discordToken, 1))
+			{
+				var connectResult = await discordProvider.Connect(default).ConfigureAwait(false);
+				Assert.IsTrue(connectResult, "Failed to connect to discord!");
+				Assert.IsTrue(discordProvider.Connected, "Discord provider is not connected!");
+
+				// Forcefully close the connection under the provider's nose
+				// This will be detected in real life scenarios
+				DiscordSocketClient socketClient = typeof(DiscordProvider)
+					.GetField("client", BindingFlags.Instance | BindingFlags.NonPublic)
+					?.GetValue(discordProvider)
+					as DiscordSocketClient;
+				Assert.IsNotNull(socketClient, "Reflection unable to read discord socket client!");
+
+				await socketClient.LogoutAsync().ConfigureAwait(false);
+
+				Assert.IsFalse(discordProvider.Connected, "Discord provider is still connected!");
+
+				try
+				{
+					using (CancellationTokenSource cts = new CancellationTokenSource(TimeSpan.FromSeconds(70)))
+					{
+						do
+						{
+							var message = await discordProvider.NextMessage(cts.Token).ConfigureAwait(false);
+							if (message == null)
+								break;
+						}
+						while (true);
+
+						// Prevents a deadlock coming from having the NextMessage continuation call Dispose
+						await Task.Yield();
+					}
+				}
+				catch (OperationCanceledException)
+				{
+					Assert.Fail("Failed to reconnect within the time period!");
+				}
+
+				Assert.IsTrue(discordProvider.Connected, "Discord provider not connected!");
+			}
+		}
+
 		[TestMethod]
-		[TestCategory("SkipWhenLiveUnitTesting")]
 		public async Task TestUpdate()
 		{
 			var updatePathRoot = Path.GetTempFileName();
@@ -95,7 +148,6 @@ namespace Tgstation.Server.Tests
 		}
 
 		[TestMethod]
-		[TestCategory("SkipWhenLiveUnitTesting")]
 		public async Task TestStandardOperation()
 		{
 			var server = new TestingServer(clientFactory, null);

tests/Tgstation.Server.Tests/Tgstation.Server.Tests.csproj

@@ -10,6 +10,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.9.0" />
+    <PackageReference Include="Moq" Version="4.13.1" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.0.0" />
     <PackageReference Include="MSTest.TestFramework" Version="2.0.0" />
   </ItemGroup>