add support for abstract domain sockets in OpenTelemetry.Exporter.Geneva

src/OpenTelemetry.Exporter.Geneva/CHANGELOG.md

@@ -5,6 +5,8 @@
 * TldLogExporter to export `SpanId` value in `ext_dt_spanId` field instead of
   `TraceId` value.
   ([#1184](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/1184))
+* Add support for abstract domain sockets
+  ([#1198](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/issues/1198))
 
 ## 1.5.0-alpha.3
 

src/OpenTelemetry.Exporter.Geneva/Internal/ConnectionStringBuilder.cs

@@ -132,12 +132,29 @@ public TransportProtocol Protocol
         }
     }
 
+    /// <summary>
+    /// Replace first charater of string if it matches with <paramref name="oldChar"/> with <paramref name="newChar"/>.
+    /// </summary>
+    /// <param name="str">String to be updated.</param>
+    /// <param name="oldChar">Old character to be replaced.</param>
+    /// <param name="newChar">New character to be replaced with.</param>
+    /// <returns>Updated string.</returns>
+    internal static string ReplaceFirstChar(string str, char oldChar, char newChar)
+    {
+        if (str.Length > 0 && str[0] == oldChar)
+        {
+            return $"{newChar}{str.Substring(1)}";
+        }
+
+        return str;
+    }
+
     public string ParseUnixDomainSocketPath()
     {
         try
         {
             var endpoint = new Uri(this.Endpoint);
-            return endpoint.AbsolutePath;
+            return ReplaceFirstChar(endpoint.AbsolutePath, '@', '\0');
         }
         catch (UriFormatException ex)
         {

test/OpenTelemetry.Exporter.Geneva.Tests/ConnectionStringBuilderTests.cs

@@ -104,6 +104,11 @@ public void ConnectionStringBuilder_Endpoint_UnixDomainSocketPath()
 
         builder = new ConnectionStringBuilder("EtwSession=OpenTelemetry");
         Assert.Throws<ArgumentException>(() => _ = builder.ParseUnixDomainSocketPath());
+
+        builder = new ConnectionStringBuilder("Endpoint=unix:@/var/run/default_fluent.socket");
+        Assert.Equal("unix:@/var/run/default_fluent.socket", builder.Endpoint);
+        Assert.Equal(TransportProtocol.Unix, builder.Protocol);
+        Assert.Equal("\0/var/run/default_fluent.socket", builder.ParseUnixDomainSocketPath());
     }
 
     [Fact]