Geneva Exporter - Throw on TableNameMappings null value

src/OpenTelemetry.Exporter.Geneva/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+* Throw exception when `TableNameMappings` contains a `null` value.
+[322](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/322)
+
 * Update OTel SDK version to `1.2.0`.
 [319](https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/319)
 

src/OpenTelemetry.Exporter.Geneva/GenevaLogExporter.cs

@@ -23,6 +23,7 @@
 using System.Text;
 using System.Threading;
 using Microsoft.Extensions.Logging;
+using OpenTelemetry.Internal;
 using OpenTelemetry.Logs;
 
 namespace OpenTelemetry.Exporter.Geneva;
@@ -64,6 +65,8 @@ public GenevaLogExporter(GenevaExporterOptions options)
             var tempTableMappings = new Dictionary<string, string>(options.TableNameMappings.Count, StringComparer.Ordinal);
             foreach (var kv in options.TableNameMappings)
             {
+                Guard.ThrowIfNull(kv.Value);
+
                 if (Encoding.UTF8.GetByteCount(kv.Value) != kv.Value.Length)
                 {
                     throw new ArgumentException("The value: \"{tableName}\" provided for TableNameMappings option contains non-ASCII characters", kv.Value);

src/OpenTelemetry.Exporter.Geneva/OpenTelemetry.Exporter.Geneva.csproj

@@ -15,5 +15,5 @@
   <ItemGroup>
     <PackageReference Include="OpenTelemetry" Version="1.2.0" />
   </ItemGroup>
-
+  
 </Project>

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

@@ -61,6 +61,14 @@ public void SpecialChractersInTableNameMappings()
                 {
                     TableNameMappings = new Dictionary<string, string> { ["*"] = "\u0418" },
                 });
+            });
+
+		    Assert.Throws<ArgumentNullException>(() =>
+            {
+                using var exporter = new GenevaLogExporter(new GenevaExporterOptions
+                {
+                    TableNameMappings = new Dictionary<string, string> { ["TestCategory"] = null },
+                });
             });
         }