Adds chat broadcasting and update channels

src/Tgstation.Server.Api/Models/ChatChannel.cs

@@ -28,5 +28,11 @@ namespace Tgstation.Server.Api.Models
 		/// </summary>
 		[Required]
 		public bool? IsWatchdogChannel { get; set; }
+
+		/// <summary>
+		/// If the <see cref="ChatChannel"/> is an updates channel
+		/// </summary>
+		[Required]
+		public bool? IsUpdatesChannel { get; set; }
 	}
 }

src/Tgstation.Server.Host/Components/Chat/ChannelMapping.cs

@@ -20,6 +20,11 @@
 		/// </summary>
 		public bool IsWatchdogChannel { get; set; }
 
+		/// <summary>
+		/// If the <see cref="Channel"/> is an updates channel
+		/// </summary>
+		public bool IsUpdatesChannel { get; set; }
+
 		/// <summary>
 		/// The <see cref="Components.Chat.Channel"/> with the mapped Id
 		/// </summary>

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

@@ -342,6 +342,7 @@ namespace Tgstation.Server.Host.Components.Chat
 			var mappings = Enumerable.Zip(newChannels, results, (x, y) => new ChannelMapping
 			{
 				IsWatchdogChannel = x.IsWatchdogChannel == true,
+				IsUpdatesChannel = x.IsUpdatesChannel == true,
 				ProviderChannelId = y.RealId,
 				ProviderId = connectionId,
 				Channel = y
@@ -456,11 +457,21 @@ namespace Tgstation.Server.Host.Components.Chat
 		public Task SendWatchdogMessage(string message, CancellationToken cancellationToken)
 		{
 			List<ulong> wdChannels;
+			message = String.Format(CultureInfo.InvariantCulture, "Watchdog: {0}", message);
 			lock (mappedChannels)   //so it doesn't change while we're using it
 				wdChannels = mappedChannels.Where(x => x.Value.IsWatchdogChannel).Select(x => x.Key).ToList();
 			return SendMessage(message, wdChannels, cancellationToken);
 		}
 
+		/// <inheritdoc />
+		public Task SendUpdateMessage(string message, CancellationToken cancellationToken)
+		{
+			List<ulong> wdChannels;
+			lock (mappedChannels)   //so it doesn't change while we're using it
+				wdChannels = mappedChannels.Where(x => x.Value.IsUpdatesChannel).Select(x => x.Key).ToList();
+			return SendMessage(message, wdChannels, cancellationToken);
+		}
+
 		/// <inheritdoc />
 		public async Task StartAsync(CancellationToken cancellationToken)
 		{
@@ -532,5 +543,14 @@ namespace Tgstation.Server.Host.Components.Chat
 					provider.Dispose();
 				}
 		}
+
+		/// <inheritdoc />
+		public Task SendBroadcast(string message, CancellationToken cancellationToken)
+		{
+			List<ulong> wdChannels;
+			lock (mappedChannels)   //so it doesn't change while we're using it
+				wdChannels = mappedChannels.Select(x => x.Key).ToList();
+			return SendMessage(message, wdChannels, cancellationToken);
+		}
 	}
 }

src/Tgstation.Server.Host/Components/Chat/IChat.cs

@@ -67,6 +67,22 @@ namespace Tgstation.Server.Host.Components.Chat
 		/// <returns>A <see cref="Task"/> representing the running operation</returns>
 		Task SendWatchdogMessage(string message, CancellationToken cancellationToken);
 
+		/// <summary>
+		/// Send a chat <paramref name="message"/> to configured update channels
+		/// </summary>
+		/// <param name="message">The message being sent</param>
+		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation</param>
+		/// <returns>A <see cref="Task"/> representing the running operation</returns>
+		Task SendUpdateMessage(string message, CancellationToken cancellationToken);
+
+		/// <summary>
+		/// Send a chat to all channels
+		/// </summary>
+		/// <param name="message">The message being sent</param>
+		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation</param>
+		/// <returns>A <see cref="Task"/> representing the running operation</returns>
+		Task SendBroadcast(string message, CancellationToken cancellationToken);
+
 		/// <summary>
 		/// Start tracking json files for commands and channels
 		/// </summary>

src/Tgstation.Server.Host/Components/InstanceManager.cs

@@ -56,6 +56,16 @@ namespace Tgstation.Server.Host.Components
 		/// </summary>
 		readonly Dictionary<string, IInteropConsumer> interopConsumers;
 
+		/// <summary>
+		/// <see cref="List{T}"/> of <see cref="Task"/>s to finish in <see cref="StopAsync(CancellationToken)"/>
+		/// </summary>
+		readonly List<Task> shutdownTasks;
+
+		/// <summary>
+		/// Used as a temporary <see cref="CancellationTokenSource"/> for <see cref="shutdownTasks"/>
+		/// </summary>
+		readonly CancellationTokenSource shutdownCancellationTokenSource;
+
 		/// <summary>
 		/// Construct an <see cref="InstanceManager"/>
 		/// </summary>
@@ -65,17 +75,30 @@ namespace Tgstation.Server.Host.Components
 		/// <param name="application">The value of <see cref="application"/></param>
 		/// <param name="jobManager">The value of <see cref="jobManager"/></param>
 		/// <param name="logger">The value of <see cref="logger"/></param>
-		public InstanceManager(IInstanceFactory instanceFactory, IIOManager ioManager, IDatabaseContextFactory databaseContextFactory, IApplication application, IJobManager jobManager, ILogger<InstanceManager> logger)
+		public InstanceManager(IInstanceFactory instanceFactory, IIOManager ioManager, IDatabaseContextFactory databaseContextFactory, IApplication application, IJobManager jobManager, IServerControl serverControl, ILogger<InstanceManager> logger)
 		{
 			this.instanceFactory = instanceFactory ?? throw new ArgumentNullException(nameof(instanceFactory));
 			this.ioManager = ioManager ?? throw new ArgumentNullException(nameof(ioManager));
 			this.databaseContextFactory = databaseContextFactory ?? throw new ArgumentNullException(nameof(databaseContextFactory));
 			this.application = application ?? throw new ArgumentNullException(nameof(application));
 			this.jobManager = jobManager ?? throw new ArgumentNullException(nameof(jobManager));
+
+			if (serverControl == null)
+				throw new ArgumentNullException(nameof(serverControl));
+
+			var cancellationToken = shutdownCancellationTokenSource.Token;
+			serverControl.RegisterForRestart(() =>
+			{
+				lock (this)
+					shutdownTasks.AddRange(instances.Select(x => x.Value.Chat.SendBroadcast("TGS: Restart requested...", cancellationToken)));
+			});
+
 			this.logger = logger ?? throw new ArgumentNullException(nameof(logger));
 
 			instances = new Dictionary<long, IInstance>();
 			interopConsumers = new Dictionary<string, IInteropConsumer>();
+			shutdownTasks = new List<Task>();
+			shutdownCancellationTokenSource = new CancellationTokenSource();
 		}
 
 		/// <inheritdoc />
@@ -83,6 +106,7 @@ namespace Tgstation.Server.Host.Components
 		{
 			foreach (var I in instances)
 				I.Value.Dispose();
+			shutdownCancellationTokenSource.Dispose();
 		}
 
 		/// <inheritdoc />
@@ -191,6 +215,8 @@ namespace Tgstation.Server.Host.Components
 		/// <inheritdoc />
 		public async Task StopAsync(CancellationToken cancellationToken)
 		{
+			using (cancellationToken.Register(() => shutdownCancellationTokenSource.Cancel()))
+				await Task.WhenAll(shutdownTasks).ConfigureAwait(false);
 			await Task.WhenAll(instances.Select(x => x.Value.StopAsync(cancellationToken))).ConfigureAwait(false);
 			await jobManager.StopAsync(cancellationToken).ConfigureAwait(false);
 		}