Disconnecting NotificationBase from Event, introducing NotificationSender

BTCPayServer/Controllers/NotificationsController.cs

@@ -22,13 +22,13 @@ namespace BTCPayServer.Controllers
     public class NotificationsController : Controller
     {
         private readonly ApplicationDbContext _db;
-        private readonly EventAggregator _eventAggregator;
+        private readonly NotificationSender _notificationSender;
         private readonly UserManager<ApplicationUser> _userManager;
 
-        public NotificationsController(ApplicationDbContext db, EventAggregator eventAggregator, UserManager<ApplicationUser> userManager)
+        public NotificationsController(ApplicationDbContext db, NotificationSender notificationSender, UserManager<ApplicationUser> userManager)
         {
             _db = db;
-            _eventAggregator = eventAggregator;
+            _notificationSender = notificationSender;
             _userManager = userManager;
         }
 
@@ -54,7 +54,7 @@ namespace BTCPayServer.Controllers
         [HttpGet]
         public async Task<IActionResult> Generate()
         {
-            _eventAggregator.NoticeNewVersion("1.0.4.4");
+            await _notificationSender.NoticeNewVersionAsync("1.0.4.4");
             // waiting for event handler to catch up
             await Task.Delay(1000);
             return RedirectToAction(nameof(Index));

BTCPayServer/Events/Notifications/NewVersionNotification.cs

@@ -4,7 +4,7 @@ using Newtonsoft.Json;
 
 namespace BTCPayServer.Events.Notifications
 {
-    internal class NewVersionNotification : NotificationEventBase
+    internal class NewVersionNotification : NotificationBase
     {
         public string Version { get; set; }
 

BTCPayServer/Events/Notifications/NotificationBase.cs

@@ -8,17 +8,18 @@ namespace BTCPayServer.Events.Notifications
     // Make sure to keep all NotificationEventBase classes in same namespace
     // because of dependent initialization and parsing to view models logic
     // IndexViewModel.cs#32
-    internal abstract class NotificationEventBase
+    internal abstract class NotificationBase
     {
         internal virtual string NotificationType { get { return GetType().Name; } }
 
-        public NotificationData ToData()
+        public NotificationData ToData(string applicationUserId)
         {
             var obj = JsonConvert.SerializeObject(this);
 
             var data = new NotificationData
             {
-                Created = DateTimeOffset.UtcNow,
+                Id = Guid.NewGuid().ToString(),
+                ApplicationUserId = applicationUserId,
                 NotificationType = NotificationType,
                 Blob = ZipUtils.Zip(obj),
                 Seen = false

BTCPayServer/Events/Notifications/NotificationEvent.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace BTCPayServer.Events.Notifications
+{
+    internal class NotificationEvent
+    {
+        internal string[] ApplicationUserIds { get; set; }
+        internal NotificationBase Notification { get; set; }
+    }
+}

BTCPayServer/Events/Notifications/NotificationsHelperExt.cs

@@ -3,17 +3,36 @@ using System.Collections.Generic;
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
+using BTCPayServer.Data;
+using Microsoft.AspNetCore.Identity;
 
 namespace BTCPayServer.Events.Notifications
 {
-    public static class NotificationsHelperExt
+    public class NotificationSender
     {
-        public static void NoticeNewVersion(this EventAggregator aggr, string version)
+        private readonly UserManager<ApplicationUser> _userManager;
+        private readonly EventAggregator _eventAggregator;
+
+        public NotificationSender(UserManager<ApplicationUser> userManager, EventAggregator eventAggregator)
         {
-            aggr.Publish(new NewVersionNotification
+            _userManager = userManager;
+            _eventAggregator = eventAggregator;
+        }
+
+        internal async Task NoticeNewVersionAsync(string version)
+        {
+            var admins = await _userManager.GetUsersInRoleAsync(Roles.ServerAdmin);
+            var adminUids = admins.Select(a => a.Id).ToArray();
+            var evt = new NotificationEvent
             {
-                Version = version
+                ApplicationUserIds = adminUids,
-            });
+                Notification = new NewVersionNotification
+                {
+                    Version = version
+                }
+            };
+
+            _eventAggregator.Publish(evt);
         }
     }
 }

BTCPayServer/HostedServices/NotificationDbSaver.cs

@@ -15,58 +15,32 @@ namespace BTCPayServer.HostedServices
 {
     public class NotificationDbSaver : EventHostedServiceBase
     {
-        private readonly UserManager<ApplicationUser> _UserManager;
         private readonly ApplicationDbContextFactory _ContextFactory;
 
-        public NotificationDbSaver(UserManager<ApplicationUser> userManager,
+        public NotificationDbSaver(ApplicationDbContextFactory contextFactory,
-                    ApplicationDbContextFactory contextFactory,
                     EventAggregator eventAggregator) : base(eventAggregator)
         {
-            _UserManager = userManager;
             _ContextFactory = contextFactory;
         }
 
         protected override void SubscribeToEvents()
         {
-            SubscribeAllChildrenOfNotificationEventBase();
+            Subscribe<NotificationEvent>();
             base.SubscribeToEvents();
         }
 
-        // subscribe all children of NotificationEventBase
-        public void SubscribeAllChildrenOfNotificationEventBase()
-        {
-            var method = this.GetType().GetMethod(nameof(SubscribeHelper));
-            var notificationTypes = this.GetType().Assembly.GetTypes().Where(a => typeof(NotificationEventBase).IsAssignableFrom(a));
-            foreach (var notif in notificationTypes)
-            {
-                var generic = method.MakeGenericMethod(notif);
-                generic.Invoke(this, null);
-            }
-        }
-
-        // we need publicly accessible method for reflection invoke
-        public void SubscribeHelper<T>() => base.Subscribe<T>();
-
         protected override async Task ProcessEvent(object evt, CancellationToken cancellationToken)
         {
-            if (evt is NotificationEventBase)
+            var casted = evt as NotificationEvent;
+            using (var db = _ContextFactory.CreateContext())
             {
-                var data = (evt as NotificationEventBase).ToData();
+                foreach (var uid in casted.ApplicationUserIds)
-
-                var admins = await _UserManager.GetUsersInRoleAsync(Roles.ServerAdmin);
-
-                using (var db = _ContextFactory.CreateContext())
                 {
-                    foreach (var admin in admins)
+                    var data = casted.Notification.ToData(uid);
-                    {
+                    db.Notifications.Add(data);
-                        data.Id = Guid.NewGuid().ToString();
-                        data.ApplicationUserId = admin.Id;
-
-                        db.Notifications.Add(data);
-                    }
-
-                    await db.SaveChangesAsync();
                 }
+
+                await db.SaveChangesAsync();
             }
         }
     }

BTCPayServer/Hosting/BTCPayServerServices.cs

@@ -46,6 +46,7 @@ using BTCPayServer.Security.Bitpay;
 using Serilog;
 using BTCPayServer.Security.GreenField;
 using BTCPayServer.Services.Labels;
+using BTCPayServer.Events.Notifications;
 
 namespace BTCPayServer.Hosting
 {
@@ -202,6 +203,7 @@ namespace BTCPayServer.Hosting
 
             services.AddSingleton<IHostedService, NotificationDbSaver>();
             services.AddScoped<NotificationManager>();
+            services.AddScoped<NotificationSender>();
 
             services.AddSingleton<IHostedService, NBXplorerWaiters>();
             services.AddSingleton<IHostedService, InvoiceNotificationManager>();

BTCPayServer/Models/NotificationViewModels/IndexViewModel.cs

@@ -29,10 +29,10 @@ namespace BTCPayServer.Models.NotificationViewModels
     {
         public static NotificationViewModel ViewModel(this NotificationData data)
         {
-            var baseType = typeof(NotificationEventBase);
+            var baseType = typeof(NotificationBase);
 
-            var typeName = baseType.FullName.Replace(nameof(NotificationEventBase), data.NotificationType, StringComparison.OrdinalIgnoreCase);
+            var typeName = baseType.FullName.Replace(nameof(NotificationBase), data.NotificationType, StringComparison.OrdinalIgnoreCase);
-            var instance = Activator.CreateInstance(baseType.Assembly.GetType(typeName)) as NotificationEventBase;
+            var instance = Activator.CreateInstance(baseType.Assembly.GetType(typeName)) as NotificationBase;
 
             return instance.ToViewModel(data);
         }