X-Splunk-Request-Channel header added

Author: Drasko Popovic

src/Serilog.Sinks.Splunk/Sinks/Splunk/EventCollectorClient.cs

@@ -21,14 +21,26 @@ namespace Serilog.Sinks.Splunk
 {
     internal class EventCollectorClient : HttpClient, IDisposable
     {
+        private const string AUTH_SCHEME = "Splunk";
+        private const string SPLUNK_REQUEST_CHANNEL = "X-Splunk-Request-Channel";
+
         public EventCollectorClient(string eventCollectorToken) : base()
         {
-            DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Splunk", eventCollectorToken);
+            SetHeaders(eventCollectorToken);
         }
 
         public EventCollectorClient(string eventCollectorToken, HttpMessageHandler messageHandler) : base(messageHandler)
         {
-            DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Splunk", eventCollectorToken);
+            SetHeaders(eventCollectorToken);
+        }
+
+        private void SetHeaders(string eventCollectorToken)
+        {
+            DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(AUTH_SCHEME, eventCollectorToken);
+            if (!this.DefaultRequestHeaders.Contains(SPLUNK_REQUEST_CHANNEL))
+            {
+                this.DefaultRequestHeaders.Add(SPLUNK_REQUEST_CHANNEL, Guid.NewGuid().ToString());
+            }
         }
     }
 }