Refactor tracing

MQTTnet.Core/Diagnostics/IMqttNetTraceHandler.cs

@@ -0,0 +1,9 @@
+namespace MQTTnet.Core.Diagnostics
+{
+    public interface IMqttNetTraceHandler
+    {
+        bool IsEnabled { get; }
+
+        void HandleTraceMessage(MqttNetTraceMessage traceMessage);
+    }
+}

MQTTnet.Core/Diagnostics/MqttNetTrace.cs

@@ -2,48 +2,62 @@
 
 namespace MQTTnet.Core.Diagnostics
 {
-    public static class MqttNetTrace
+    public sealed class MqttNetTrace : IMqttNetTraceHandler
     {
+        private readonly IMqttNetTraceHandler _traceHandler;
+
+        public MqttNetTrace(IMqttNetTraceHandler traceHandler = null)
+        {
+            _traceHandler = traceHandler ?? this;
+        }
+        
         public static event EventHandler<MqttNetTraceMessagePublishedEventArgs> TraceMessagePublished;
 
-        public static void Verbose(string source, string message, params object[] parameters)
+        public bool IsEnabled => TraceMessagePublished != null;
+
+        public void Verbose(string source, string message, params object[] parameters)
         {
             Publish(source, MqttNetTraceLevel.Verbose, null, message, parameters);
         }
 
-        public static void Information(string source, string message, params object[] parameters)
+        public void Information(string source, string message, params object[] parameters)
         {
             Publish(source, MqttNetTraceLevel.Information, null, message, parameters);
         }
 
-        public static void Warning(string source, string message, params object[] parameters)
+        public void Warning(string source, string message, params object[] parameters)
         {
             Publish(source, MqttNetTraceLevel.Warning, null, message, parameters);
         }
 
-        public static void Warning(string source, Exception exception, string message, params object[] parameters)
+        public void Warning(string source, Exception exception, string message, params object[] parameters)
         {
             Publish(source, MqttNetTraceLevel.Warning, exception, message, parameters);
         }
 
-        public static void Error(string source, string message, params object[] parameters)
+        public void Error(string source, string message, params object[] parameters)
         {
             Publish(source, MqttNetTraceLevel.Error, null, message, parameters);
         }
 
-        public static void Error(string source, Exception exception, string message, params object[] parameters)
+        public void Error(string source, Exception exception, string message, params object[] parameters)
         {
             Publish(source, MqttNetTraceLevel.Error, exception, message, parameters);
         }
 
-        private static void Publish(string source, MqttNetTraceLevel traceLevel, Exception exception, string message, params object[] parameters)
+        public void HandleTraceMessage(MqttNetTraceMessage mqttNetTraceMessage)
         {
-            var handler = TraceMessagePublished;
-            if (handler == null)
+            TraceMessagePublished?.Invoke(this, new MqttNetTraceMessagePublishedEventArgs(mqttNetTraceMessage));
+        }
+
+        private void Publish(string source, MqttNetTraceLevel traceLevel, Exception exception, string message, params object[] parameters)
+        {
+            if (!_traceHandler.IsEnabled)
             {
                 return;
             }
 
+            var now = DateTime.Now;
             if (parameters?.Length > 0)
             {
                 try
@@ -57,7 +71,7 @@ namespace MQTTnet.Core.Diagnostics
                 }
             }
 
-            handler.Invoke(null, new MqttNetTraceMessagePublishedEventArgs(Environment.CurrentManagedThreadId, source, traceLevel, message, exception));
+            _traceHandler.HandleTraceMessage(new MqttNetTraceMessage(now, Environment.CurrentManagedThreadId, source, traceLevel, message, exception));
         }
     }
 }

MQTTnet.Core/Diagnostics/MqttNetTraceMessage.cs

@@ -0,0 +1,29 @@
+using System;
+
+namespace MQTTnet.Core.Diagnostics
+{
+    public sealed class MqttNetTraceMessage
+    {
+        public MqttNetTraceMessage(DateTime timestamp, int threadId, string source, MqttNetTraceLevel level, string message, Exception exception)
+        {
+            Timestamp = timestamp;
+            ThreadId = threadId;
+            Source = source;
+            Level = level;
+            Message = message;
+            Exception = exception;
+        }
+
+        public DateTime Timestamp { get; }
+
+        public int ThreadId { get; }
+
+        public string Source { get; }
+
+        public MqttNetTraceLevel Level { get; }
+
+        public string Message { get; }
+
+        public Exception Exception { get; }
+    }
+}

MQTTnet.Core/Diagnostics/MqttNetTraceMessagePublishedEventArgs.cs

@@ -4,23 +4,11 @@ namespace MQTTnet.Core.Diagnostics
 {
     public sealed class MqttNetTraceMessagePublishedEventArgs : EventArgs
     {
-        public MqttNetTraceMessagePublishedEventArgs(int threadId, string source, MqttNetTraceLevel level, string message, Exception exception)
+        public MqttNetTraceMessagePublishedEventArgs(MqttNetTraceMessage traceMessage)
         {
-            ThreadId = threadId;
-            Source = source;
-            Level = level;
-            Message = message;
-            Exception = exception;
+            TraceMessage = traceMessage ?? throw new ArgumentNullException(nameof(traceMessage));
         }
 
-        public int ThreadId { get; }
-
-        public string Source { get; }
-
-        public MqttNetTraceLevel Level { get; }
-
-        public string Message { get; }
-
-        public Exception Exception { get; }
+        public MqttNetTraceMessage TraceMessage { get; }
     }
 }