Redis presence manager

samples/ChatSample/HubWithPresence.cs

@@ -1,7 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.SignalR;
@@ -24,12 +23,9 @@ namespace ChatSample
             _userTracker = userTracker;
         }
 
-        public Task<IEnumerable<UserDetails>> UsersOnline
+        public Task<IEnumerable<UserDetails>> GetUsersOnline()
         {
-            get
+            return _userTracker.UsersOnline();
-            {
-                return _userTracker.UsersOnline();
-            }
         }
 
         public virtual Task OnUserJoined(UserDetails user)

samples/ChatSample/Hubs/Chat.cs

@@ -20,9 +20,10 @@ namespace ChatSample.Hubs
             if (!Context.User.Identity.IsAuthenticated)
             {
                 Context.Connection.Dispose();
+                return;
             }
 
-            await Clients.Client(Context.ConnectionId).InvokeAsync("SetUsersOnline", await UsersOnline);
+            await Clients.Client(Context.ConnectionId).InvokeAsync("SetUsersOnline", await GetUsersOnline());
             await base.OnConnectedAsync();
         }
 

samples/ChatSample/IUserTracker.cs

@@ -11,8 +11,8 @@ namespace ChatSample
     public interface IUserTracker<out THub>
     {
         Task<IEnumerable<UserDetails>> UsersOnline();
-        Task AddUser(Connection connection, UserDetails user);
+        Task AddUser(Connection connection, UserDetails userDetails);
-        Task<UserDetails> RemoveUser(Connection connection);
+        Task RemoveUser(Connection connection);
 
         event Action<UserDetails> UserJoined;
         event Action<UserDetails> UserLeft;

samples/ChatSample/InMemoryUserTracker.cs

@@ -18,22 +18,22 @@ namespace ChatSample
         public Task<IEnumerable<UserDetails>> UsersOnline()
             => Task.FromResult(_usersOnline.Values.AsEnumerable());
 
-        public Task AddUser(Connection connection, UserDetails user)
+        public Task AddUser(Connection connection, UserDetails userDetails)
         {
-            _usersOnline.TryAdd(connection, user);
+            _usersOnline.TryAdd(connection, userDetails);
-            UserJoined(user);
+            UserJoined(userDetails);
 
             return Task.CompletedTask;
         }
 
-        public Task<UserDetails> RemoveUser(Connection connection)
+        public Task RemoveUser(Connection connection)
         {
             if (_usersOnline.TryRemove(connection, out var userDetails))
             {
                 UserLeft(userDetails);
             }
 
-            return Task.FromResult(userDetails);
+            return Task.CompletedTask;
         }
     }
 }

samples/ChatSample/PresenceHubLifetimeManager.cs

@@ -1,10 +1,13 @@
-
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
 using System;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.SignalR;
 using Microsoft.AspNetCore.Sockets;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using Microsoft.AspNetCore.SignalR.Redis;
 
 namespace ChatSample
 {
@@ -18,6 +21,16 @@ namespace ChatSample
         }
     }
 
+    public class RedisPresenceHublifetimeMenager<THub> : PresenceHubLifetimeManager<THub, RedisHubLifetimeManager<THub>>
+    where THub : HubWithPresence
+    {
+        public RedisPresenceHublifetimeMenager(IUserTracker<THub> userTracker, IServiceScopeFactory serviceScopeFactory,
+            ILoggerFactory loggerFactory, IServiceProvider serviceProvider)
+            : base(userTracker, serviceScopeFactory, loggerFactory, serviceProvider)
+        {
+        }
+    }
+
     public class PresenceHubLifetimeManager<THub, THubLifetimeManager> : HubLifetimeManager<THub>, IDisposable
         where THubLifetimeManager : HubLifetimeManager<THub>
         where THub : HubWithPresence

samples/ChatSample/RedisUserTracker.cs

@@ -1,53 +1,37 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
-/*
 using System;
-using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
+using System.Net;
 using System.Text;
 using System.Threading.Tasks;
-using Microsoft.AspNetCore.SignalR;
 using Microsoft.AspNetCore.SignalR.Redis;
 using Microsoft.AspNetCore.Sockets;
-using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
 using StackExchange.Redis;
 
 namespace ChatSample
 {
-    public class RedisPresenceManager<THub> : IDisposable, IUserTracker<THub> where THub : HubWithPresence
+    public class RedisUserTracker<THub> : IUserTracker<THub>
     {
         private readonly RedisKey UsersOnlineRedisKey = "UsersOnline";
-        private readonly RedisChannel _redisChannel;
-
-        private IHubContext<THub> _hubContext;
-        private HubLifetimeManager<THub> _lifetimeManager;
-        private readonly IServiceScopeFactory _serviceScopeFactory;
         private readonly int _redisDatabase;
         private readonly ConnectionMultiplexer _redisConnection;
         private readonly ISubscriber _redisSubscriber;
         private readonly ILogger _logger;
+        private readonly RedisChannel _redisChannel;
 
-        private readonly ConcurrentDictionary<Connection, object> _connections
+        public event Action<UserDetails> UserJoined;
-            = new ConcurrentDictionary<Connection, object>();
+        public event Action<UserDetails> UserLeft;
 
-        // TODO: subscribe and handle lifecycle events/disconnects
+        public RedisUserTracker(IOptions<RedisOptions> options, ILoggerFactory loggerFactory)
-        // TODO: handle situations where Redis shuts down
-        // TODO: handle situations where a server goes down and the server has zombie connections
-
-        public RedisPresenceManager(IHubContext<THub> hubContext, HubLifetimeManager<THub> lifetimeManager,
-            IServiceScopeFactory serviceScopeFactory, IOptions<RedisOptions> options, ILoggerFactory loggerFactory)
         {
-            _hubContext = hubContext;
+            _logger = loggerFactory.CreateLogger<RedisUserTracker<THub>>();
-            _lifetimeManager = lifetimeManager;
-            _serviceScopeFactory = serviceScopeFactory;
-
-            _logger = loggerFactory.CreateLogger<RedisPresenceManager<THub>>();
             _redisDatabase = options.Value.Options.DefaultDatabase.GetValueOrDefault();
             _redisConnection = ConnectToRedis(options.Value, _logger);
             _redisSubscriber = _redisConnection.GetSubscriber();
@@ -59,11 +43,11 @@ namespace ChatSample
                 var user = ToUserDetails(stringValue.Substring(1));
                 if (stringValue[0] == '-')
                 {
-                    _ = Notify(hub => hub.OnUserLeft(user));
+                    UserLeft(user);
                 }
                 else
                 {
-                    _ = Notify(hub => hub.OnUserJoined(user));
+                    UserJoined(user);
                 }
             });
         }
@@ -71,17 +55,20 @@ namespace ChatSample
         private static ConnectionMultiplexer ConnectToRedis(RedisOptions options, ILogger logger)
         {
             var loggerTextWriter = new LoggerTextWriter(logger);
-            return options.Factory == null
+            if (options.Factory != null)
-                ? ConnectionMultiplexer.Connect(options.Options, loggerTextWriter)
+            {
-                : options.Factory(loggerTextWriter);
+                return options.Factory(loggerTextWriter);
-        }
+            }
 
-        public async Task<IEnumerable<UserDetails>> UsersOnline()
+            if (options.Options.EndPoints.Any())
-        {
+            {
-            var database = _redisConnection.GetDatabase(_redisDatabase);
+                return ConnectionMultiplexer.Connect(options.Options, loggerTextWriter);
-            var usersOnline = await database.SetMembersAsync(UsersOnlineRedisKey);
+            }
 
-            return usersOnline.Select(u => ToUserDetails(u));
+            var configurationOptions = new ConfigurationOptions();
+            configurationOptions.EndPoints.Add(IPAddress.Loopback, 0);
+            configurationOptions.SetDefaultPorts();
+            return ConnectionMultiplexer.Connect(configurationOptions, loggerTextWriter);
         }
 
         private static UserDetails ToUserDetails(string user)
@@ -91,66 +78,30 @@ namespace ChatSample
             return new UserDetails(user.Substring(0, pos), user.Substring(pos + 1));
         }
 
-        public Task UserJoined(Connection connection)
+        public async Task AddUser(Connection connection, UserDetails userDetails)
         {
-            _connections.TryAdd(connection, null);
-
             var database = _redisConnection.GetDatabase(_redisDatabase);
             var user = $"{connection.ConnectionId}|{connection.User.Identity.Name}";
-            // Fire and forget
+
-            _ = database.SetAddAsync(UsersOnlineRedisKey, $"{connection.ConnectionId}|{connection.User.Identity.Name}");
+            // need to await to make sure user is added before we call into the Hub
+            await database.SetAddAsync(UsersOnlineRedisKey, $"{connection.ConnectionId}|{connection.User.Identity.Name}");
             _ = _redisSubscriber.PublishAsync(_redisChannel, "+" + user);
-
-            return Task.CompletedTask;
         }
 
-        public Task UserLeft(Connection connection)
+        public async Task RemoveUser(Connection connection)
         {
-            _connections.TryRemove(connection, out object _);
-
             var database = _redisConnection.GetDatabase(_redisDatabase);
             var user = $"{connection.ConnectionId}|{connection.User.Identity.Name}";
-            // Fire and forget
+
-            _ = database.SetRemoveAsync(UsersOnlineRedisKey, user);
+            await database.SetRemoveAsync(UsersOnlineRedisKey, user);
             _ = _redisSubscriber.PublishAsync(_redisChannel, "-" + user);
-
-            return Task.CompletedTask;
         }
 
-        private async Task Notify(Func<THub, Task> invocation)
+        public async Task<IEnumerable<UserDetails>> UsersOnline()
         {
-            foreach (var connection in _connections.Keys)
+            var database = _redisConnection.GetDatabase(_redisDatabase);
-            {
+            var usersOnline = await database.SetMembersAsync(UsersOnlineRedisKey);
-                using (var scope = _serviceScopeFactory.CreateScope())
+            return usersOnline.Select(u => ToUserDetails(u));
-                {
-                    var hubActivator = scope.ServiceProvider.GetRequiredService<IHubActivator<THub, IClientProxy>>();
-                    var hub = hubActivator.Create();
-
-                    hub.Clients = _hubContext.Clients;
-                    hub.Context = new HubCallerContext(connection);
-                    hub.Groups = new GroupManager<THub>(connection, _lifetimeManager);
-
-                    try
-                    {
-                        await invocation(hub);
-                    }
-                    catch (Exception ex)
-                    {
-                        _logger.LogWarning(ex, "Presence notification failed.");
-                    }
-                    finally
-                    {
-                        hubActivator.Release(hub);
-                    }
-                }
-            }
-        }
-
-        public void Dispose()
-        {
-            _redisSubscriber.Unsubscribe(_redisChannel);
-            _redisConnection.Close();
-            _redisConnection.Dispose();
         }
 
         private class LoggerTextWriter : TextWriter
@@ -171,8 +122,8 @@ namespace ChatSample
             public override void WriteLine(string value)
             {
                 _logger.LogDebug(value);
+
             }
         }
     }
-}
+}
-*/

samples/ChatSample/Startup.cs

@@ -9,6 +9,7 @@ using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
 using Microsoft.AspNetCore.SignalR;
+using Microsoft.AspNetCore.SignalR.Redis;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
@@ -54,15 +55,22 @@ namespace ChatSample
             services.AddTransient<IEmailSender, AuthMessageSender>();
             services.AddTransient<ISmsSender, AuthMessageSender>();
 
-            // To use Redis scaleout uncomment .AddRedis
+            // To use Redis scaleout uncomment .AddRedis and uncomment Redis related lines below for presence
             services.AddSignalR()
                 // .AddRedis()
                 ;
             services.AddAuthentication();
 
+
             services.AddSingleton(typeof(DefaultHubLifetimeManager<>), typeof(DefaultHubLifetimeManager<>));
             services.AddSingleton(typeof(HubLifetimeManager<>), typeof(DefaultPresenceHublifetimeMenager<>));
             services.AddSingleton(typeof(IUserTracker<>), typeof(InMemoryUserTracker<>));
+
+            /*
+            services.AddSingleton(typeof(RedisHubLifetimeManager<>), typeof(RedisHubLifetimeManager<>));
+            services.AddSingleton(typeof(HubLifetimeManager<>), typeof(RedisPresenceHublifetimeMenager<>));
+            services.AddSingleton(typeof(IUserTracker<>), typeof(RedisUserTracker<>));
+            */
         }
 
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.