Handle json messages

changelog.md

@@ -1,4 +1,10 @@
 # Changelog
+
+## [5.1.0] - 2026-05-18
+### *Changes*
+- Add JsonMessageHandler<T> abstract base class for type-safe message consumption with automatic JSON deserialization
+- Add optional JsonSerializerOptions parameter to JsonMessagePublisher<T>
+
 ## [5.0.0] - 2026-05-12
 ### *Changes (Breaking)*
 - Target .NET 10

src/JsonMessageHandler.cs

@@ -0,0 +1,21 @@
+using System.Text.Json;
+
+namespace Linn.Common.Messaging.RabbitMQ;
+
+public abstract class JsonMessageHandler<T>(JsonSerializerOptions? serializerOptions = null) : IMessageHandler
+{
+    public abstract string RoutingKey { get; }
+
+    public async Task HandleAsync(Message message, CancellationToken cancellationToken)
+    {
+        var payload = JsonSerializer.Deserialize<T>(message.Body.Span, serializerOptions)
+            ?? throw new JsonException($"Failed to deserialize message body to {typeof(T).Name}");
+
+        await HandleAsync(payload, message.Headers, cancellationToken);
+    }
+
+    protected abstract Task HandleAsync(
+        T payload,
+        IReadOnlyDictionary<string, object> headers,
+        CancellationToken cancellationToken);
+}

src/JsonMessagePublisher.cs

@@ -5,15 +5,16 @@ namespace Linn.Common.Messaging.RabbitMQ;
 public class JsonMessagePublisher<T>(
     RabbitPublisher rabbitPublisher,
     string routingKey,
-    IReadOnlyDictionary<string, object>? headers = null)
+    IReadOnlyDictionary<string, object>? headers = null,
+    JsonSerializerOptions? serializerOptions = null)
     : IPublisher<T>
 {
     public async Task PublishAsync(T obj, CancellationToken cancellationToken = default)
     {
         var msg = new Message
         {
             RoutingKey = routingKey,
-            Body = JsonSerializer.SerializeToUtf8Bytes(obj),
+            Body = JsonSerializer.SerializeToUtf8Bytes(obj, serializerOptions),
             Headers = headers ?? new Dictionary<string, object>()
         };