Added MQTT logging. Closes GH-604

src/Transports/MQTT/Wolverine.MQTT/Internals/MqttNetLogger.cs

@@ -0,0 +1,39 @@
+using Microsoft.Extensions.Logging;
+using MQTTnet.Client;
+using MQTTnet.Diagnostics;
+
+namespace Wolverine.MQTT.Internals;
+
+public class MqttNetLogger : IMqttNetLogger
+{
+    private readonly ILogger _logger;
+
+    public MqttNetLogger(ILogger<MqttClient> logger)
+    {
+        _logger = logger;
+    }
+
+    public void Publish(MqttNetLogLevel logLevel, string source, string message, object[] parameters, Exception exception)
+    {
+        switch (logLevel)
+        {
+            case MqttNetLogLevel.Error:
+                _logger.LogError(exception, message, parameters);
+                break;
+
+            case MqttNetLogLevel.Info:
+                _logger.LogInformation(message, parameters);
+                break;
+
+            case MqttNetLogLevel.Warning:
+                _logger.LogWarning(message, parameters);
+                break;
+
+            case MqttNetLogLevel.Verbose:
+                _logger.LogDebug(message, parameters);
+                break;
+        }
+    }
+
+    public bool IsEnabled => _logger.IsEnabled(LogLevel.Debug);
+}

src/Transports/MQTT/Wolverine.MQTT/Internals/MqttTransport.cs

@@ -58,8 +58,8 @@ public override async ValueTask InitializeAsync(IWolverineRuntime runtime)
 
         var mqttFactory = new MqttFactory();
 
-        // TODO -- add logging here!
-        Client = mqttFactory.CreateManagedMqttClient();
+        var logger = new MqttNetLogger(runtime.LoggerFactory.CreateLogger<MqttClient>());
+        Client = mqttFactory.CreateManagedMqttClient(logger);
 
         Options.ClientOptions.ProtocolVersion = MqttProtocolVersion.V500;