optimise codes

src/Infrastructure.EventBus/GlobalUsings.cs

@@ -1,5 +1,4 @@
 // Global using directives
 
 global using Microsoft.Extensions.Logging;
-global using Newtonsoft.Json;
 global using RabbitMQ.Client;

src/Infrastructure.EventBus/IEventBus.cs

@@ -1,10 +1,12 @@
-namespace Infrastructure.EventBus;
+namespace Roller.Infrastructure.EventBus;
 
 public interface IEventBus
 {
-    void Publish(IntegrationEvent integrationEvent);
+    void Publish<TEvent>(TEvent integrationEvent) where TEvent : IntegrationEvent;
 
-    void Subscribe<TEvent, TEventHandler>() where TEvent : IntegrationEvent where TEventHandler : IIntegrationEventHandler<TEvent>;
+    void Subscribe<TEvent, TEventHandler>() where TEvent : IntegrationEvent
+        where TEventHandler : IIntegrationEventHandler<TEvent>;
 
-    void Unsubscribe<TEvent, TEventHandler>() where TEventHandler : IIntegrationEventHandler<TEvent> where TEvent : IntegrationEvent;
+    void Unsubscribe<TEvent, TEventHandler>() where TEventHandler : IIntegrationEventHandler<TEvent>
+        where TEvent : IntegrationEvent;
 }

src/Infrastructure.EventBus/IIntegrationEventHandler.cs

@@ -1,4 +1,4 @@
-namespace Infrastructure.EventBus;
+namespace Roller.Infrastructure.EventBus;
 
 public interface IIntegrationEventHandler<in TIntegrationEvent>
     where TIntegrationEvent : IntegrationEvent

src/Infrastructure.EventBus/IntegrationEvent.cs

@@ -1,4 +1,6 @@
-namespace Infrastructure.EventBus;
+using Newtonsoft.Json;
+
+namespace Roller.Infrastructure.EventBus;
 
 [method: JsonConstructor]
 public class IntegrationEvent(Guid id, DateTime createdDate)

src/Infrastructure.EventBus/RabbitMQ/IPersistentConnection.cs

@@ -1,6 +1,6 @@
-namespace Infrastructure.EventBus.RabbitMQ;
+namespace Roller.Infrastructure.EventBus.RabbitMQ;
 
-public interface IPersistentConnection : IDisposable
+public interface IPersistentConnection
 {
     event EventHandler OnReconnectedAfterConnectionFailure;
     bool IsConnected { get; }

src/Infrastructure.EventBus/RabbitMQ/RabbitMQEventBus.cs

@@ -1,46 +1,50 @@
 using System.Net.Sockets;
-using System.Reflection;
 using System.Text;
-using Infrastructure.EventBus.Subscriptions;
-using Infrastructure.Utils;
+using System.Text.Json;
 using Polly;
 using RabbitMQ.Client.Events;
 using RabbitMQ.Client.Exceptions;
+using Roller.Infrastructure.EventBus.Subscriptions;
 
-namespace Infrastructure.EventBus.RabbitMQ;
+namespace Roller.Infrastructure.EventBus.RabbitMQ;
 
 public class RabbitMQEventBus : IEventBus
 {
-    private readonly IPersistentConnection _persistentConnection;
-    private readonly ILogger<RabbitMQEventBus> _logger;
-    private readonly IServiceProvider _serviceProvider;
-    private readonly IEventBusSubscriptionManager _eventBusSubscriptionManager;
     private readonly string _exchangeName;
     private readonly string _queueName;
+    private readonly int _publishRetryCount = 5;
+    private readonly TimeSpan _subscribeRetryTime = TimeSpan.FromSeconds(5);
 
-    public RabbitMQEventBus(IPersistentConnection persistentConnection,
-        ILogger<RabbitMQEventBus> logger,
+    private readonly IPersistentConnection _persistentConnection;
+    private readonly IEventBusSubscriptionManager _subscriptionsManager;
+    private readonly IServiceProvider _serviceProvider;
+
+    private readonly ILogger<RabbitMQEventBus> _logger;
+
+    private IModel _consumerChannel;
+
+    public RabbitMQEventBus(
+        IPersistentConnection persistentConnection,
+        IEventBusSubscriptionManager subscriptionsManager,
         IServiceProvider serviceProvider,
-        IEventBusSubscriptionManager eventBusSubscriptionManager,
-        string exchangeName,
+        ILogger<RabbitMQEventBus> logger,
+        string brokerName,
         string queueName)
     {
-        _persistentConnection = persistentConnection;
-        _logger = logger;
+        _persistentConnection = persistentConnection ?? throw new ArgumentNullException(nameof(persistentConnection));
+        _subscriptionsManager = subscriptionsManager ?? throw new ArgumentNullException(nameof(subscriptionsManager));
         _serviceProvider = serviceProvider;
-        _eventBusSubscriptionManager = eventBusSubscriptionManager;
-        _exchangeName = exchangeName;
-        _queueName = queueName;
+        _logger = logger;
+        _exchangeName = brokerName ?? throw new ArgumentNullException(nameof(brokerName));
+        _queueName = queueName ?? throw new ArgumentNullException(nameof(queueName));
+
         ConfigureMessageBroker();
     }
 
-    private readonly int _publishRetryCount = 5;
-    private IModel _consumerChannel;
-    private readonly TimeSpan _subscribeRetryTime = TimeSpan.FromSeconds(5);
-
-    public void Publish(IntegrationEvent integrationEvent)
+    public void Publish<TEvent>(TEvent @event)
+        where TEvent : IntegrationEvent
     {
-        if (_persistentConnection.IsConnected)
+        if (!_persistentConnection.IsConnected)
         {
             _persistentConnection.TryConnect();
         }
@@ -52,93 +56,110 @@ public class RabbitMQEventBus : IEventBus
                 (exception, timeSpan) =>
                 {
                     _logger.LogWarning(exception,
-                        "Could not publish event #{EventId} after {Timeout} seconds: {ExceptionMessage}.",
-                        integrationEvent.Id,
+                        "Could not publish event #{EventId} after {Timeout} seconds: {ExceptionMessage}.", @event.Id,
                         $"{timeSpan.TotalSeconds:n1}", exception.Message);
                 });
-        var eventName = integrationEvent.GetType().Name;
-        _logger.LogTrace("Creating RabbitMQ channel to publish event #{EventId} ({EventName})...", integrationEvent.Id,
+
+        var eventName = @event.GetType().Name;
+
+        _logger.LogTrace("Creating RabbitMQ channel to publish event #{EventId} ({EventName})...", @event.Id,
             eventName);
+
         using var channel = _persistentConnection.CreateModel();
-        _logger.LogTrace("Declaring RabbitMQ exchange to publish event #{EventId}...", integrationEvent.Id);
+        _logger.LogTrace("Declaring RabbitMQ exchange to publish event #{EventId}...", @event.Id);
+
         channel.ExchangeDeclare(exchange: _exchangeName, type: "direct");
 
-        var message = integrationEvent.Serialize();
+        var message = JsonSerializer.Serialize(@event);
         var body = Encoding.UTF8.GetBytes(message);
+
         policy.Execute(() =>
         {
             var properties = channel.CreateBasicProperties();
             properties.DeliveryMode = 2;
-            _logger.LogTrace("Publishing event to RabbitMQ with ID #{EventId}...", integrationEvent.Id);
+
+            _logger.LogTrace("Publishing event to RabbitMQ with ID #{EventId}...", @event.Id);
+
             channel.BasicPublish(
                 exchange: _exchangeName,
                 routingKey: eventName,
                 mandatory: true,
                 basicProperties: properties,
                 body: body);
-            _logger.LogTrace("Published event with ID #{EventId}.", integrationEvent.Id);
+
+            _logger.LogTrace("Published event with ID #{EventId}.", @event.Id);
         });
     }
 
-    public void Subscribe<TEvent, TEventHandler>() where TEvent : IntegrationEvent
+    public void Subscribe<TEvent, TEventHandler>()
+        where TEvent : IntegrationEvent
         where TEventHandler : IIntegrationEventHandler<TEvent>
     {
-        var eventName = _eventBusSubscriptionManager.GetEventIdentifier<TEvent>();
+        var eventName = _subscriptionsManager.GetEventIdentifier<TEvent>();
         var eventHandlerName = typeof(TEventHandler).Name;
+
         AddQueueBindForEventSubscription(eventName);
+
         _logger.LogInformation("Subscribing to event {EventName} with {EventHandler}...", eventName, eventHandlerName);
-        _eventBusSubscriptionManager.AddSubscription<TEvent, TEventHandler>();
+
+        _subscriptionsManager.AddSubscription<TEvent, TEventHandler>();
+        StartBasicConsume();
+
         _logger.LogInformation("Subscribed to event {EventName} with {EvenHandler}.", eventName, eventHandlerName);
     }
 
-    public void Unsubscribe<TEvent, TEventHandler>() where TEvent : IntegrationEvent
+    public void Unsubscribe<TEvent, TEventHandler>()
+        where TEvent : IntegrationEvent
         where TEventHandler : IIntegrationEventHandler<TEvent>
     {
-        var eventName = _eventBusSubscriptionManager.GetEventIdentifier<TEvent>();
+        var eventName = _subscriptionsManager.GetEventIdentifier<TEvent>();
+
         _logger.LogInformation("Unsubscribing from event {EventName}...", eventName);
 
-        _eventBusSubscriptionManager.RemoveSubscription<TEvent, TEventHandler>();
+        _subscriptionsManager.RemoveSubscription<TEvent, TEventHandler>();
 
         _logger.LogInformation("Unsubscribed from event {EventName}.", eventName);
     }
 
-
     private void ConfigureMessageBroker()
     {
         _consumerChannel = CreateConsumerChannel();
-        _eventBusSubscriptionManager.OnEventRemoved += SubscriptionManager_OnEventRemoved;
+        _subscriptionsManager.OnEventRemoved += SubscriptionManager_OnEventRemoved;
         _persistentConnection.OnReconnectedAfterConnectionFailure +=
             PersistentConnection_OnReconnectedAfterConnectionFailure;
     }
 
-    private void PersistentConnection_OnReconnectedAfterConnectionFailure(object sender, EventArgs e)
+    private IModel CreateConsumerChannel()
     {
-        DoCreateConsumerChannel();
-        RecreateSubscriptions();
+        if (!_persistentConnection.IsConnected)
+        {
+            _persistentConnection.TryConnect();
         }
 
-    private void RecreateSubscriptions()
-    {
-        var subscriptions = _eventBusSubscriptionManager.GetAllSubscriptions();
-        _eventBusSubscriptionManager.Clear();
+        _logger.LogTrace("Creating RabbitMQ consumer channel...");
 
-        var eventBusType = this.GetType();
+        var channel = _persistentConnection.CreateModel();
 
-        foreach (var entry in subscriptions)
-        {
-            foreach (var genericSubscribe in entry.Value.Select(subscription => eventBusType.GetMethod("Subscribe")
-                         .MakeGenericMethod(subscription.EventType, subscription.HandlerType)))
-            {
-                genericSubscribe.Invoke(this, null);
-            }
-        }
-    }
+        channel.ExchangeDeclare(exchange: _exchangeName, type: "direct");
+        channel.QueueDeclare
+        (
+            queue: _queueName,
+            durable: true,
+            exclusive: false,
+            autoDelete: false,
+            arguments: null
+        );
 
-    private void DoCreateConsumerChannel()
+        channel.CallbackException += (sender, ea) =>
         {
-        _consumerChannel.Dispose();
-        _consumerChannel = CreateConsumerChannel();
-        StartBasicConsume();
+            _logger.LogWarning(ea.Exception, "Recreating RabbitMQ consumer channel...");
+            DoCreateConsumerChannel();
+        };
+
+        _logger.LogTrace("Created RabbitMQ consumer channel.");
+
+
+        return channel;
     }
 
     private void StartBasicConsume()
@@ -191,7 +212,6 @@ public class RabbitMQEventBus : IEventBus
         }
     }
 
-
     private async Task TryEnqueueMessageAgainAsync(BasicDeliverEventArgs eventArgs)
     {
         try
@@ -214,13 +234,13 @@ public class RabbitMQEventBus : IEventBus
     {
         _logger.LogTrace("Processing RabbitMQ event: {EventName}...", eventName);
 
-        if (!_eventBusSubscriptionManager.HasSubscriptionsForEvent(eventName))
+        if (!_subscriptionsManager.HasSubscriptionsForEvent(eventName))
         {
             _logger.LogTrace("There are no subscriptions for this event.");
             return;
         }
 
-        var subscriptions = _eventBusSubscriptionManager.GetHandlersForEvent(eventName);
+        var subscriptions = _subscriptionsManager.GetHandlersForEvent(eventName);
         foreach (var subscription in subscriptions)
         {
             var handler = _serviceProvider.GetService(subscription.HandlerType);
@@ -230,9 +250,9 @@ public class RabbitMQEventBus : IEventBus
                 continue;
             }
 
-            var eventType = _eventBusSubscriptionManager.GetEventTypeByName(eventName);
+            var eventType = _subscriptionsManager.GetEventTypeByName(eventName);
 
-            var @event = JsonConvert.DeserializeObject(message, eventType);
+            var @event = JsonSerializer.Deserialize(message, eventType);
             var eventHandlerType = typeof(IIntegrationEventHandler<>).MakeGenericType(eventType);
             await Task.Yield();
             await (Task)eventHandlerType.GetMethod(nameof(IIntegrationEventHandler<IntegrationEvent>.HandleAsync))
@@ -252,57 +272,57 @@ public class RabbitMQEventBus : IEventBus
         using var channel = _persistentConnection.CreateModel();
         channel.QueueUnbind(queue: _queueName, exchange: _exchangeName, routingKey: eventName);
 
-        if (_eventBusSubscriptionManager.IsEmpty)
+        if (_subscriptionsManager.IsEmpty)
         {
             _consumerChannel.Close();
         }
     }
 
-    private IModel CreateConsumerChannel()
+    private void AddQueueBindForEventSubscription(string eventName)
+    {
+        var containsKey = _subscriptionsManager.HasSubscriptionsForEvent(eventName);
+        if (containsKey)
         {
+            return;
+        }
+
         if (!_persistentConnection.IsConnected)
         {
             _persistentConnection.TryConnect();
         }
 
-        _logger.LogTrace("Creating RabbitMQ consumer channel...");
-
-        var channel = _persistentConnection.CreateModel();
-
-        channel.ExchangeDeclare(exchange: _exchangeName, type: "direct");
-        channel.QueueDeclare
-        (
-            queue: _queueName,
-            durable: true,
-            exclusive: false,
-            autoDelete: false,
-            arguments: null
-        );
+        using var channel = _persistentConnection.CreateModel();
+        channel.QueueBind(queue: _queueName, exchange: _exchangeName, routingKey: eventName);
+    }
 
-        channel.CallbackException += (_, ea) =>
+    private void PersistentConnection_OnReconnectedAfterConnectionFailure(object sender, EventArgs e)
     {
-            _logger.LogWarning(ea.Exception, "Recreating RabbitMQ consumer channel...");
         DoCreateConsumerChannel();
-        };
-
-        _logger.LogTrace("Created RabbitMQ consumer channel.");
-        return channel;
+        RecreateSubscriptions();
     }
 
-    private void AddQueueBindForEventSubscription(string eventName)
-    {
-        var containsKey = _eventBusSubscriptionManager.HasSubscriptionsForEvent(eventName);
-        if (containsKey)
+    private void DoCreateConsumerChannel()
     {
-            return;
+        _consumerChannel.Dispose();
+        _consumerChannel = CreateConsumerChannel();
+        StartBasicConsume();
     }
 
-        if (!_persistentConnection.IsConnected)
+    private void RecreateSubscriptions()
     {
-            _persistentConnection.TryConnect();
-        }
+        var subscriptions = _subscriptionsManager.GetAllSubscriptions();
+        _subscriptionsManager.Clear();
 
-        using var channel = _persistentConnection.CreateModel();
-        channel.QueueBind(queue: _queueName, exchange: _exchangeName, routingKey: eventName);
+        var eventBusType = GetType();
+
+        foreach (var entry in subscriptions)
+        {
+            foreach (var subscription in entry.Value)
+            {
+                var genericSubscribe = eventBusType.GetMethod("Subscribe")
+                    .MakeGenericMethod(subscription.EventType, subscription.HandlerType);
+                genericSubscribe.Invoke(this, null);
+            }
+        }
     }
 }

src/Infrastructure.EventBus/RabbitMQ/RabbitMQPersistentConnection.cs

@@ -4,7 +4,7 @@ using Polly;
 using RabbitMQ.Client.Events;
 using RabbitMQ.Client.Exceptions;
 
-namespace Infrastructure.EventBus.RabbitMQ;
+namespace Roller.Infrastructure.EventBus.RabbitMQ;
 
 public class RabbitMQPersistentConnection(
     IConnectionFactory connectionFactory,
@@ -26,7 +26,7 @@ public class RabbitMQPersistentConnection(
 
         lock (_locker)
         {
-            // Creates a policy to retry connecting to message broker until it succeeds.
+            // Creates a policy to retry connecting to message broker until it succeds.
             var policy = Policy
                 .Handle<SocketException>()
                 .Or<BrokerUnreachableException>()
@@ -47,7 +47,7 @@ public class RabbitMQPersistentConnection(
                 return false;
             }
 
-            // These event handlers hadle situations where the connection is lost by any reason. They try to reconnect the client.
+            // These event handlers hanle situations where the connection is lost by any reason. They try to reconnect the client.
             _connection.ConnectionShutdown += OnConnectionShutdown;
             _connection.CallbackException += OnCallbackException;
             _connection.ConnectionBlocked += OnConnectionBlocked;
@@ -59,13 +59,12 @@ public class RabbitMQPersistentConnection(
 
             // If the connection has failed previously because of a RabbitMQ shutdown or something similar, we need to guarantee that the exchange and queues exist again.
             // It's also necessary to rebind all application event handlers. We use this event handler below to do this.
-            if (!_connectionFailed)
+            if (_connectionFailed)
             {
-                return true;
-            }
-
                 OnReconnectedAfterConnectionFailure?.Invoke(this, null);
                 _connectionFailed = false;
+            }
+
             return true;
         }
     }
@@ -74,7 +73,7 @@ public class RabbitMQPersistentConnection(
     {
         if (!IsConnected)
         {
-            throw new InvalidOperationException("No RabbitMQ connections are available to perform this action");
+            throw new InvalidOperationException("No RabbitMQ connections are available to perform this action.");
         }
 
         return _connection.CreateModel();

src/Infrastructure.EventBus/RabbitMQ/RabbitMqConnectionOptions.cs

@@ -0,0 +1,26 @@
+namespace Roller.Infrastructure.EventBus.RabbitMQ;
+
+public class RabbitMqConnectionOptions
+{
+    public const string SectionName = "RabbitMQ";
+
+    public const string USER = "RABBITMQ_USER";
+
+    public const string PASSWORD = "RABBITMQ_PASSWORD";
+
+    public const string HOST = "RABBITMQ_HOST";
+
+    public required string Username { get; set; }
+
+    public required string Password { get; set; }
+
+    public required string HostName { get; set; }
+
+    public required string ExchangeName { get; set; }
+
+    public required string QueueName { get; set; }
+
+    public int TimeoutBeforeReconnecting { get; set; }
+
+    public bool DispatchConsumersAsync { get; set; } = true;
+}

src/Infrastructure.EventBus/ServiceCollectionExtensions.cs

@@ -0,0 +1,45 @@
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+using Roller.Infrastructure.EventBus.RabbitMQ;
+using Roller.Infrastructure.EventBus.Subscriptions;
+
+namespace Roller.Infrastructure.EventBus;
+
+public static class ServiceCollectionExtensions
+{
+    public static IServiceCollection AddRollerRabbitMQEventBus(this IServiceCollection services,
+        IConfiguration configuration)
+    {
+        ArgumentNullException.ThrowIfNull(configuration);
+        ArgumentNullException.ThrowIfNull(services);
+
+        var rabbitMqOptions = configuration.GetSection(RabbitMqConnectionOptions.SectionName)
+            .Get<RabbitMqConnectionOptions>();
+        ArgumentNullException.ThrowIfNull(rabbitMqOptions);
+        services.AddSingleton<IEventBusSubscriptionManager, InMemoryEventBusSubscriptionManager>();
+        services.AddSingleton<IPersistentConnection, RabbitMQPersistentConnection>(factory =>
+        {
+            var connectionFactory = new ConnectionFactory
+            {
+                HostName = configuration[RabbitMqConnectionOptions.HOST] ?? rabbitMqOptions.HostName,
+                UserName = configuration[RabbitMqConnectionOptions.USER] ?? rabbitMqOptions.Username,
+                Password = configuration[RabbitMqConnectionOptions.PASSWORD] ?? rabbitMqOptions.Password,
+                DispatchConsumersAsync = rabbitMqOptions.DispatchConsumersAsync,
+            };
+
+            var logger = factory.GetService<ILogger<RabbitMQPersistentConnection>>();
+            return new RabbitMQPersistentConnection(connectionFactory, logger,
+                rabbitMqOptions.TimeoutBeforeReconnecting);
+        });
+        services.AddSingleton<IEventBus, RabbitMQEventBus>(factory =>
+        {
+            var persistentConnection = factory.GetService<IPersistentConnection>();
+            var subscriptionManager = factory.GetService<IEventBusSubscriptionManager>();
+            var logger = factory.GetService<ILogger<RabbitMQEventBus>>();
+
+            return new RabbitMQEventBus(persistentConnection, subscriptionManager, factory, logger,
+                rabbitMqOptions.ExchangeName, rabbitMqOptions.QueueName);
+        });
+        return services;
+    }
+}

src/Infrastructure.EventBus/Subscriptions/IEventBusSubscriptionManager.cs

@@ -1,4 +1,4 @@
-namespace Infrastructure.EventBus.Subscriptions;
+namespace Roller.Infrastructure.EventBus.Subscriptions;
 
 public interface IEventBusSubscriptionManager
 {

src/Infrastructure.EventBus/Subscriptions/InMemoryEventBusSubscriptionManager.cs

@@ -1,4 +1,4 @@
-namespace Infrastructure.EventBus.Subscriptions;
+namespace Roller.Infrastructure.EventBus.Subscriptions;
 
 public class InMemoryEventBusSubscriptionManager : IEventBusSubscriptionManager
 {

src/Infrastructure.EventBus/Subscriptions/Subscription.cs

@@ -1,4 +1,4 @@
-namespace Infrastructure.EventBus.Subscriptions;
+namespace Roller.Infrastructure.EventBus.Subscriptions;
 
 public class Subscription
 {