Fix initialization bugs (#8)

* update nuspec

* fix bug in ProfilerFrontEndClientFactory

* fix bug in ProfilerFrontEndClientFactory

* fix bug in ProfilerFrontEndClientFactory

* fix typo

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: j-zhong-ms <107880703+j-zhong-ms@users.noreply.github.com>

---------

Signed-off-by: j-zhong-ms <107880703+j-zhong-ms@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

src/ServiceProfiler.EventPipe.Otel/Azure.Monitor.OpenTelemetry.Profiler.Core/Azure.Monitor.OpenTelemetry.Profiler.Core.nuspec

@@ -50,6 +50,8 @@
     <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.Contract.Agent.pdb" target="lib/$targetFramework$"></file>
     <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.Contract.Agent.Profiler.dll" target="lib/$targetFramework$"></file>
     <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.Contract.Agent.Profiler.pdb" target="lib/$targetFramework$"></file>
+    <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.HttpPipeline.dll" target="lib/$targetFramework$"></file>
+    <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.HttpPipeline.pdb" target="lib/$targetFramework$"></file>
     <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.Logging.dll" target="lib/$targetFramework$"></file>
     <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.Logging.pdb" target="lib/$targetFramework$"></file>
     <file src="bin\$configuration$\$targetFramework$\Microsoft.ServiceProfiler.Orchestration.dll" target="lib/$targetFramework$"></file>

src/ServiceProfiler.EventPipe.Otel/Microsoft.ApplicationInsights.Profiler.Shared/Services/ProfilerFrontendClientFactory.cs

@@ -43,9 +43,11 @@ public IProfilerFrontendClient CreateProfilerFrontendClient()
             ActivatorUtilities.CreateInstance<AADAuthTokenCredential>(_serviceProvider) :
             null;
 
-        return ActivatorUtilities.CreateInstance<ProfilerFrontendClient>(
-            _serviceProvider,
-            _serviceProfilerContext.StampFrontendEndpointUrl,
+        // ActivatorUtilities is not used for creating ProfilerFrontendClient due to its limitation in handling nullable parameters.
+        // For example, when credential is null, it will throw InvalidOperationException:
+        // A suitable constructor for type 'Microsoft.ServiceProfiler.Agent.FrontendClient.ProfilerFrontendClient' could not be located.
+        // Because CreateProfilerFrontendClient method is only called in ServiceCollectionExtensions, it will be disposed by the service provider.
+        return new ProfilerFrontendClient(_serviceProfilerContext.StampFrontendEndpointUrl,
             _serviceProfilerContext.AppInsightsInstrumentationKey,
             _serviceProfilerContext.MachineName,
             "1.0.0",