⚡ Optimize push notification saving by introducing the flush buffer

DysonNetwork.Pusher/Notification/NotificationFlushHandler.cs

@@ -0,0 +1,28 @@
+using DysonNetwork.Shared.Cache;
+using EFCore.BulkExtensions;
+using NodaTime;
+using Quartz;
+
+namespace DysonNetwork.Pusher.Notification;
+
+public class NotificationFlushHandler(AppDatabase db, Logger<NotificationFlushHandler> logger) : IFlushHandler<Notification>
+{
+    public async Task FlushAsync(IReadOnlyList<Notification> items)
+    {
+        await db.BulkInsertAsync(items.Select(x =>
+        {
+            x.CreatedAt = SystemClock.Instance.GetCurrentInstant();
+            x.UpdatedAt = x.CreatedAt;
+            return x;
+        }), config => config.ConflictOption = ConflictOption.Ignore);
+        logger.LogInformation("Stored {Count} notifications", items.Count);
+    }
+}
+
+public class NotificationFlushJob(FlushBufferService fbs, NotificationFlushHandler hdl) : IJob
+{
+    public async Task Execute(IJobExecutionContext context)
+    {
+        await fbs.FlushAsync(hdl);
+    }
+}

DysonNetwork.Pusher/Notification/PushService.cs

@@ -1,6 +1,7 @@
 using CorePush.Apple;
 using CorePush.Firebase;
 using DysonNetwork.Pusher.Connection;
+using DysonNetwork.Shared.Cache;
 using DysonNetwork.Shared.Proto;
 using EFCore.BulkExtensions;
 using Microsoft.EntityFrameworkCore;
@@ -11,6 +12,7 @@ namespace DysonNetwork.Pusher.Notification;
 public class PushService
 {
     private readonly AppDatabase _db;
+    private readonly FlushBufferService _fbs;
     private readonly WebSocketService _ws;
     private readonly ILogger<PushService> _logger;
     private readonly FirebaseSender? _fcm;
@@ -20,6 +22,7 @@ public class PushService
     public PushService(
         IConfiguration config,
         AppDatabase db,
+        FlushBufferService fbs,
         WebSocketService ws,
         IHttpClientFactory httpFactory,
         ILogger<PushService> logger
@@ -50,6 +53,7 @@ public class PushService
         }
 
         _db = db;
+        _fbs = fbs;
         _ws = ws;
         _logger = logger;
     }
@@ -112,11 +116,12 @@ public class PushService
         string? title = null,
         string? subtitle = null,
         string? content = null,
-        Dictionary<string, object?> meta = null,
+        Dictionary<string, object?>? meta = null,
         string? actionUri = null,
         bool isSilent = false,
         bool save = true)
     {
+        meta ??= [];
         if (title is null && subtitle is null && content is null)
             throw new ArgumentException("Unable to send notification that completely empty.");
 
@@ -134,10 +139,7 @@ public class PushService
         };
 
         if (save)
-        {
+            _fbs.Enqueue(notification);
-            _db.Add(notification);
-            await _db.SaveChangesAsync();
-        }
 
         if (!isSilent) _ = DeliveryNotification(notification);
     }
@@ -174,8 +176,7 @@ public class PushService
     public async Task SendNotificationBatch(Notification notification, List<Guid> accounts, bool save = false)
     {
         if (save)
-        {
+            accounts.ForEach(x =>
-            var notifications = accounts.Select(x =>
             {
                 var newNotification = new Notification
                 {
@@ -187,10 +188,8 @@ public class PushService
                     Priority = notification.Priority,
                     AccountId = x
                 };
-                return newNotification;
+                _fbs.Enqueue(newNotification);
-            }).ToList();
+            });
-            await _db.BulkInsertAsync(notifications);
-        }
 
         _logger.LogInformation(
             "Delivering notification in batch: {NotificationTopic} #{NotificationId} with meta {NotificationMeta}",

DysonNetwork.Pusher/Program.cs

@@ -24,7 +24,6 @@ builder.Services.AddAppFlushHandlers();
 
 // Add business services
 builder.Services.AddAppBusinessServices();
-builder.Services.AddPushServices(builder.Configuration);
 
 // Add scheduled jobs
 builder.Services.AddAppScheduledJobs();

DysonNetwork.Pusher/Startup/ScheduledJobsConfiguration.cs

@@ -1,3 +1,4 @@
+using DysonNetwork.Pusher.Notification;
 using Quartz;
 
 namespace DysonNetwork.Pusher.Startup;
@@ -14,6 +15,13 @@ public static class ScheduledJobsConfiguration
                 .ForJob(appDatabaseRecyclingJob)
                 .WithIdentity("AppDatabaseRecyclingTrigger")
                 .WithCronSchedule("0 0 0 * * ?"));
+
+            var notificationFlushJob = new JobKey("NotificationFlush");
+            q.AddJob<NotificationFlushJob>(opts => opts.WithIdentity(notificationFlushJob));
+            q.AddTrigger(opts => opts
+                .ForJob(notificationFlushJob)
+                .WithIdentity("NotificationFlushTrigger")
+                .WithSimpleSchedule(a => a.WithIntervalInSeconds(60).RepeatForever()));
         });
         services.AddQuartzHostedService(q => q.WaitForJobsToComplete = true);
 

DysonNetwork.Pusher/Startup/ServiceCollectionExtensions.cs

@@ -127,6 +127,7 @@ public static class ServiceCollectionExtensions
     public static IServiceCollection AddAppFlushHandlers(this IServiceCollection services)
     {
         services.AddSingleton<FlushBufferService>();
+        services.AddScoped<NotificationFlushHandler>();
 
         return services;
     }
@@ -139,13 +140,4 @@ public static class ServiceCollectionExtensions
 
         return services;
     }
-    
-    public static void AddPushServices(this IServiceCollection services, IConfiguration configuration)
-    {
-        services.Configure<ApnSettings>(configuration.GetSection("PushNotify:Apple"));
-        services.AddHttpClient<ApnSender>();
-
-        services.Configure<FirebaseSettings>(configuration.GetSection("PushNotify:Firebase"));
-        services.AddHttpClient<FirebaseSettings>();
-    }
 }