Fix NoCode instrumentation for generic classes and methods

Author: Kielek

CHANGELOG.md

@@ -36,6 +36,8 @@ This component adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.h
 
 ### Fixed
 
+- Fixed configuration based instrumentation for generic classes and methods.
+
 ## [1.13.0](https://github.com/open-telemetry/opentelemetry-dotnet-instrumentation/releases/tag/v1.13.0)
 
 This release include all changes from [1.13.0-beta.1](https://github.com/open-telemetry/opentelemetry-dotnet-instrumentation/releases/tag/v1.13.0-beta.1)

docs/nocode-instrumentation.md

@@ -393,6 +393,68 @@ instrumentation/development:
             kind: internal
 ```
 
+### Generic Class Instrumentation
+
+Instrument methods in generic classes with class-level type parameters:
+
+```csharp
+public class GenericNoCodeTestingClass<TFooClass, TBarClass>
+{
+    public TFooMethod GenericTestMethod<TFooMethod, TBarMethod>(
+        TFooMethod fooMethod, 
+        TBarMethod barMethod, 
+        TFooClass fooClass, 
+        TBarClass barClass)
+    {
+        return fooMethod;
+    }
+}
+```
+
+For generic classes, use the backtick notation with the number of class-level
+type parameters:
+
+Generic Type Parameter Notation:
+
+- Class-level type parameters: Use `!!0`, `!!1`, etc. (where `!!0` is the first
+  class type parameter)
+- Method-level type parameters: Use `!0`, `!1`, etc. (where `!0` is the first
+  method type parameter)
+- In the type name, use backtick notation: `ClassName\`N` where N is the number
+  of generic parameters
+
+Configuration:
+
+```yaml
+instrumentation/development:
+  dotnet:
+    no_code:
+      targets:
+        - target:
+            assembly:
+              name: TestApplication.NoCode
+            type: TestApplication.NoCode.GenericNoCodeTestingClass`2
+            method: GenericTestMethod
+            signature:
+              return_type: '!0'
+              parameter_types:
+                - '!0'
+                - '!1'
+                - '!!0'
+                - '!!1'
+          span:
+            name: Span-GenericTestMethodWithParameters
+            kind: internal
+```
+
+In this example:
+
+- `GenericNoCodeTestingClass\`2` indicates a class with 2 generic type parameters
+- `'!0'` represents the first method type parameter (`TFooMethod`)
+- `'!1'` represents the second method type parameter (`TBarMethod`)
+- `'!!0'` represents the first class type parameter (`TFooClass`)
+- `'!!1'` represents the second class type parameter (`TBarClass`)
+
 ### Methods with Return Values
 
 Instrument methods that return values:

src/OpenTelemetry.AutoInstrumentation/Instrumentations/NoCode/NoCodeIntegrationHelper.cs

@@ -128,12 +128,28 @@ private static bool CheckParameters(string[] targetSignatureTypes, ParameterInfo
 
         for (var i = 0; i < parameters.Length; i++)
         {
-            if (targetSignatureTypes[i + 1] != parameters[i].ParameterType.FullName)
+            var parameterTypeNameDefinition = GetParameterTypeNameDefinition(parameters[i]);
+            if (targetSignatureTypes[i + 1] != parameterTypeNameDefinition)
             {
                 return false;
             }
         }
 
         return true;
     }
+
+    private static string GetParameterTypeNameDefinition(ParameterInfo parameterInfo)
+    {
+        if (parameterInfo.ParameterType.IsGenericParameter)
+        {
+            var definedOnMethod = parameterInfo.ParameterType.DeclaringMethod != null;
+            var genericParameterPosition = parameterInfo.ParameterType.GenericParameterPosition;
+
+            return definedOnMethod
+                ? $"!!{genericParameterPosition}"
+                : $"!{genericParameterPosition}";
+        }
+
+        return parameterInfo.ParameterType.FullName!;
+    }
 }

test/IntegrationTests/NoCodeTests.cs

@@ -101,6 +101,7 @@ public void SubmitsTraces()
 
         collector.ExpectNoCode("Span-GenericTestMethod");
         collector.ExpectAsyncNoCode("Span-GenericTestMethodAsync");
+        collector.ExpectNoCode("Span-GenericTestMethodWithParameters");
 
         RunTestApplication();
 

test/test-applications/integrations/TestApplication.NoCode/GenericNoCodeTestingClass.cs

@@ -0,0 +1,15 @@
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+using System.Runtime.CompilerServices;
+
+namespace TestApplication.NoCode;
+
+internal class GenericNoCodeTestingClass<TFooClass, TBarClass>
+{
+    [MethodImpl(MethodImplOptions.NoInlining)]
+    public TFooMethod GenericTestMethod<TFooMethod, TBarMethod>(TFooMethod fooMethod, TBarMethod barMethod, TFooClass fooClass, TBarClass barClass)
+    {
+        return fooMethod;
+    }
+}

test/test-applications/integrations/TestApplication.NoCode/Program.cs

@@ -12,6 +12,7 @@ public static async Task Main(string[] args)
         ConsoleHelper.WriteSplashScreen(args);
 
         var noCodeTestingClass = new NoCodeTestingClass();
+        var genericNoCodeTestingClass = new GenericNoCodeTestingClass<int, long>();
 
         noCodeTestingClass.TestMethod();
         noCodeTestingClass.TestMethodA();
@@ -67,5 +68,6 @@ public static async Task Main(string[] args)
 
         _ = noCodeTestingClass.GenericTestMethod<int>();
         _ = await noCodeTestingClass.GenericTestMethodAsync<int>();
+        _ = genericNoCodeTestingClass.GenericTestMethod(string.Empty, new object(), 123, 456L);
     }
 }

test/test-applications/integrations/TestApplication.NoCode/config.yaml

@@ -650,3 +650,17 @@ instrumentation/development:
               parameter_types:
           span:
              name: Span-GenericTestMethodAsync
+        - target:
+            assembly:
+              name: TestApplication.NoCode
+            type: TestApplication.NoCode.GenericNoCodeTestingClass`2
+            method: GenericTestMethod
+            signature:
+              return_type: '!!0'
+              parameter_types:
+                - '!!0'
+                - '!!1'
+                - '!0'
+                - '!1'
+          span:
+             name: Span-GenericTestMethodWithParameters