Update: SignalR 2.0.3 Migration; Noticeboards

Migrate all SignalR 1.x Persistent Connections to SignalR 2.x Hubs.
Abstracts ScheduledTaskStatus with core interface and adds a Mock for
optional status reporting. Noticeboards rewritten (with new theme) to be
more resilient and accurate.

Disco.Services/Users/UserExtensions.cs

@@ -1,10 +1,6 @@
 using Disco.Models.Repository;
 using Disco.Services.Interop.ActiveDirectory;
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
 
 namespace Disco.Services
 {
@@ -15,6 +11,11 @@ namespace Disco.Services
             return u.Domain.Equals(ActiveDirectory.Context.PrimaryDomain.NetBiosName, StringComparison.OrdinalIgnoreCase);
         }
 
+        public static string ToStringFriendly(this User u)
+        {
+            return string.Format("{0} ({1})", u.DisplayName, u.FriendlyId());
+        }
+
         public static string FriendlyId(this User u)
         {
             return FriendlyUserId(u.UserId);

Disco.Services/Users/UserUpdatesHub.cs

@@ -0,0 +1,86 @@
+using Disco.Data.Repository.Monitor;
+using Disco.Services.Authorization;
+using Disco.Services.Web.Signalling;
+using Microsoft.AspNet.SignalR;
+using Microsoft.AspNet.SignalR.Hubs;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Reactive.Linq;
+using Disco.Models.Repository;
+using Disco.Data.Repository;
+
+namespace Disco.Services.Users
+{
+    [HubName("userUpdates"), DiscoHubAuthorizeAll(Claims.User.Show, Claims.User.ShowAttachments)]
+    public class UserUpdatesHub : Hub
+    {
+        private const string UserPrefix = "User_";
+        public static IHubContext HubContext { get; private set; }
+
+        private static IDisposable RepositoryBeforeSubscription;
+        private static IDisposable RepositoryAfterSubscription;
+
+        static UserUpdatesHub()
+        {
+            HubContext = GlobalHost.ConnectionManager.GetHubContext<UserUpdatesHub>();
+
+            // Subscribe to Repository Monitor for Changes
+            RepositoryBeforeSubscription = RepositoryMonitor.StreamBeforeCommit
+                .Where(e => e.EntityType == typeof(UserAttachment) && e.EventType == RepositoryMonitorEventType.Deleted)
+                .Subscribe(RepositoryEventBefore);
+            RepositoryAfterSubscription = RepositoryMonitor.StreamAfterCommit
+                .Where(e => e.EntityType == typeof(UserAttachment) && e.EventType == RepositoryMonitorEventType.Added)
+                .Subscribe(RepositoryAfterEvent);
+        }
+
+        private static string GroupName(string UserId)
+        {
+            return UserPrefix + UserId;
+        }
+
+        public override Task OnConnected()
+        {
+            var userId = Context.QueryString["UserId"];
+
+            if (string.IsNullOrWhiteSpace(userId))
+                throw new ArgumentNullException("UserId");
+
+            Groups.Add(Context.ConnectionId, GroupName(userId));
+
+            return base.OnConnected();
+        }
+
+        private static void RepositoryEventBefore(RepositoryMonitorEvent e)
+        {
+            if (e.EventType == RepositoryMonitorEventType.Deleted)
+            {
+                if (e.EntityType == typeof(UserAttachment))
+                {
+                    var repositoryAttachment = (UserAttachment)e.Entity;
+                    string attachmentUserId;
+
+                    using (DiscoDataContext Database = new DiscoDataContext())
+                        attachmentUserId = Database.UserAttachments.Where(a => a.Id == repositoryAttachment.Id).Select(a => a.UserId).First();
+
+                    HubContext.Clients.Group(GroupName(attachmentUserId)).removeAttachment(repositoryAttachment.Id);
+                }
+            }
+        }
+
+        private static void RepositoryAfterEvent(RepositoryMonitorEvent e)
+        {
+            if (e.EventType == RepositoryMonitorEventType.Added)
+            {
+                if (e.EntityType == typeof(UserAttachment))
+                {
+                    var a = (UserAttachment)e.Entity;
+
+                    HubContext.Clients.Group(GroupName(a.UserId)).addAttachment(a.Id);
+                }
+            }
+        }
+    }
+}