♻️ Refactored the queue

DysonNetwork.Pusher/Services/PusherServiceGrpc.cs

@@ -5,19 +5,21 @@ using DysonNetwork.Shared.Proto;
 using DysonNetwork.Shared.Registry;
 using Google.Protobuf.WellKnownTypes;
 using Grpc.Core;
+using System.Text.Json;
 
 namespace DysonNetwork.Pusher.Services;
 
 public class PusherServiceGrpc(
-    EmailService emailService,
+    QueueService queueService,
     WebSocketService websocket,
     PushService pushService,
-    AccountClientHelper accountsHelper
+    AccountClientHelper accountsHelper,
+    EmailService emailService
 ) : PusherService.PusherServiceBase
 {
     public override async Task<Empty> SendEmail(SendEmailRequest request, ServerCallContext context)
     {
-        await emailService.SendEmailAsync(
+        await queueService.EnqueueEmail(
             request.Email.ToName,
             request.Email.ToAddress,
             request.Email.Subject,
@@ -47,13 +49,16 @@ public class PusherServiceGrpc(
             Data = GrpcTypeHelper.ConvertByteStringToObject<Dictionary<string, object?>>(request.Packet.Data),
             ErrorMessage = request.Packet.ErrorMessage
         };
+        
         foreach (var userId in request.UserIds)
+        {
             websocket.SendPacketToAccount(userId, packet);
-
+        }
+        
         return Task.FromResult(new Empty());
     }
 
-    public override Task<Empty> PushWebSocketPacketToDevice(PushWebSocketPacketToDeviceRequest request,
+public override Task<Empty> PushWebSocketPacketToDevice(PushWebSocketPacketToDeviceRequest request,
         ServerCallContext context)
     {
         var packet = new Connection.WebSocketPacket
@@ -75,29 +80,38 @@ public class PusherServiceGrpc(
             Data = GrpcTypeHelper.ConvertByteStringToObject<Dictionary<string, object?>>(request.Packet.Data),
             ErrorMessage = request.Packet.ErrorMessage
         };
+        
         foreach (var deviceId in request.DeviceIds)
+        {
             websocket.SendPacketToDevice(deviceId, packet);
-
+        }
+        
         return Task.FromResult(new Empty());
     }
 
     public override async Task<Empty> SendPushNotificationToUser(SendPushNotificationToUserRequest request,
         ServerCallContext context)
     {
-        var account = await accountsHelper.GetAccount(Guid.Parse(request.UserId));
-        await pushService.SendNotification(
-            account,
-            request.Notification.Topic,
-            request.Notification.Title,
-            request.Notification.Subtitle,
-            request.Notification.Body,
-            request.Notification.HasMeta
+        var notification = new Notification.Notification
+        {
+            Topic = request.Notification.Topic,
+            Title = request.Notification.Title,
+            Subtitle = request.Notification.Subtitle,
+            Content = request.Notification.Body,
+            Meta = request.Notification.HasMeta
                 ? GrpcTypeHelper.ConvertByteStringToObject<Dictionary<string, object?>>(request.Notification.Meta) ?? []
-                : [],
-            request.Notification.ActionUri,
-            request.Notification.IsSilent,
+                : []
+        };
+        
+        if (request.Notification.ActionUri is not null)
+            notification.Meta["action_uri"] = request.Notification.ActionUri;
+            
+        await queueService.EnqueuePushNotification(
+            notification,
+            Guid.Parse(request.UserId),
             request.Notification.IsSavable
         );
+        
         return new Empty();
     }
 
@@ -114,10 +128,18 @@ public class PusherServiceGrpc(
                 ? GrpcTypeHelper.ConvertByteStringToObject<Dictionary<string, object?>>(request.Notification.Meta) ?? []
                 : [],
         };
+        
         if (request.Notification.ActionUri is not null)
             notification.Meta["action_uri"] = request.Notification.ActionUri;
-        var accounts = request.UserIds.Select(Guid.Parse).ToList();
-        await pushService.SendNotificationBatch(notification, accounts, request.Notification.IsSavable);
+            
+        var tasks = request.UserIds
+            .Select(userId => queueService.EnqueuePushNotification(
+                notification,
+                Guid.Parse(userId),
+                request.Notification.IsSavable
+            ));
+            
+        await Task.WhenAll(tasks);
         return new Empty();
     }
 

DysonNetwork.Pusher/Services/QueueBackgroundService.cs

@@ -0,0 +1,135 @@
+using System.Text.Json;
+using DysonNetwork.Pusher.Email;
+using DysonNetwork.Pusher.Notification;
+using DysonNetwork.Shared.Proto;
+using DysonNetwork.Shared.Registry;
+using NATS.Client.Core;
+
+namespace DysonNetwork.Pusher.Services;
+
+public class QueueBackgroundService(
+    INatsConnection nats,
+    IServiceProvider serviceProvider,
+    ILogger<QueueBackgroundService> logger,
+    IConfiguration configuration
+)
+    : BackgroundService
+{
+    private const string QueueName = "pusher.queue";
+    private const string QueueGroup = "pusher.workers";
+    private readonly int _consumerCount = configuration.GetValue<int?>("ConsumerCount") ?? Environment.ProcessorCount;
+    private readonly List<Task> _consumerTasks = [];
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        logger.LogInformation("Starting {ConsumerCount} queue consumers", _consumerCount);
+
+        // Start multiple consumers
+        for (var i = 0; i < _consumerCount; i++)
+            _consumerTasks.Add(Task.Run(() => RunConsumerAsync(stoppingToken), stoppingToken));
+
+        // Wait for all consumers to complete
+        await Task.WhenAll(_consumerTasks);
+    }
+
+    private async Task RunConsumerAsync(CancellationToken stoppingToken)
+    {
+        logger.LogInformation("Queue consumer started");
+
+        await foreach (var msg in nats.SubscribeAsync<QueueMessage>(
+                           QueueName,
+                           queueGroup: QueueGroup,
+                           cancellationToken: stoppingToken))
+        {
+            try
+            {
+                await ProcessMessageAsync(msg, stoppingToken);
+            }
+            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested)
+            {
+                // Normal shutdown
+                break;
+            }
+            catch (Exception ex)
+            {
+                logger.LogError(ex, "Error in queue consumer");
+                // Add a small delay to prevent tight error loops
+                await Task.Delay(1000, stoppingToken);
+            }
+        }
+    }
+
+    private async ValueTask ProcessMessageAsync(NatsMsg<QueueMessage> msg, CancellationToken cancellationToken)
+    {
+        using var scope = serviceProvider.CreateScope();
+        var message = msg.Data;
+
+        logger.LogDebug("Processing message of type {MessageType}", message.Type);
+
+        try
+        {
+            switch (message.Type)
+            {
+                case QueueMessageType.Email:
+                    await ProcessEmailMessageAsync(message, scope, cancellationToken);
+                    break;
+
+                case QueueMessageType.PushNotification:
+                    await ProcessPushNotificationMessageAsync(message, scope, cancellationToken);
+                    break;
+
+                default:
+                    logger.LogWarning("Unknown message type: {MessageType}", message.Type);
+                    break;
+            }
+
+            await msg.ReplyAsync();
+        }
+        catch (Exception ex)
+        {
+            logger.LogError(ex, "Error processing message of type {MessageType}", message.Type);
+            // Don't rethrow to prevent the message from being retried indefinitely
+            // In a production scenario, you might want to implement a dead-letter queue
+        }
+    }
+
+    private static async Task ProcessEmailMessageAsync(QueueMessage message, IServiceScope scope,
+        CancellationToken cancellationToken)
+    {
+        var emailService = scope.ServiceProvider.GetRequiredService<EmailService>();
+        var emailMessage = JsonSerializer.Deserialize<EmailMessage>(message.Data)
+                           ?? throw new InvalidOperationException("Invalid email message format");
+
+        await emailService.SendEmailAsync(
+            emailMessage.ToName,
+            emailMessage.ToAddress,
+            emailMessage.Subject,
+            emailMessage.Body);
+    }
+
+    private static async Task ProcessPushNotificationMessageAsync(QueueMessage message, IServiceScope scope,
+        CancellationToken cancellationToken)
+    {
+        var pushService = scope.ServiceProvider.GetRequiredService<PushService>();
+        var logger = scope.ServiceProvider.GetRequiredService<ILogger<QueueBackgroundService>>();
+
+        var notification = JsonSerializer.Deserialize<Notification.Notification>(message.Data);
+        if (notification == null)
+        {
+            logger.LogError("Invalid push notification data format");
+            return;
+        }
+
+        try
+        {
+            logger.LogDebug("Processing push notification for account {AccountId}", notification.AccountId);
+            await pushService.DeliverPushNotification(notification, cancellationToken);
+            logger.LogDebug("Successfully processed push notification for account {AccountId}", notification.AccountId);
+        }
+        catch (Exception ex)
+        {
+            logger.LogError(ex, "Error processing push notification for account {AccountId}", notification.AccountId);
+            // Don't rethrow to prevent the message from being retried indefinitely
+        }
+    }
+}

DysonNetwork.Pusher/Services/QueueService.cs

@@ -0,0 +1,61 @@
+using System.Text.Json;
+using NATS.Client.Core;
+
+namespace DysonNetwork.Pusher.Services;
+
+public class QueueService(INatsConnection nats)
+{
+    private const string QueueName = "pusher_queue";
+
+    public async Task EnqueueEmail(string toName, string toAddress, string subject, string body)
+    {
+        var message = new QueueMessage
+        {
+            Type = QueueMessageType.Email,
+            Data = JsonSerializer.Serialize(new EmailMessage
+            {
+                ToName = toName,
+                ToAddress = toAddress,
+                Subject = subject,
+                Body = body
+            })
+        };
+        await nats.PublishAsync(QueueName, message);
+    }
+
+    public async Task EnqueuePushNotification(Notification.Notification notification, Guid userId, bool isSavable = false)
+    {
+        // Update the account ID in case it wasn't set
+        notification.AccountId = userId;
+        
+        var message = new QueueMessage
+        {
+            Type = QueueMessageType.PushNotification,
+            TargetId = userId.ToString(),
+            Data = JsonSerializer.Serialize(notification)
+        };
+        
+        await nats.PublishAsync(QueueName, message);
+    }
+}
+
+public class QueueMessage
+{
+    public QueueMessageType Type { get; set; }
+    public string? TargetId { get; set; }
+    public string Data { get; set; } = string.Empty;
+}
+
+public enum QueueMessageType
+{
+    Email,
+    PushNotification
+}
+
+public class EmailMessage
+{
+    public string ToName { get; set; } = string.Empty;
+    public string ToAddress { get; set; } = string.Empty;
+    public string Subject { get; set; } = string.Empty;
+    public string Body { get; set; } = string.Empty;
+}