AspNet Net 6.0: FileLoadException: Could not load file or assembly 'System.Diagnostics.DiagnosticSource, Version=7.0.0.0

[ggallotti]

Question

When using the latest version of the OpenTelemetry NuGet package (currently 1.4.0-rc.1) an AspNetCore Net6.0 fails to start because OTel has taken a dependency on System.Diagnostics.DiagnosticSource 7.0.0.

  <ItemGroup>
	  <PackageReference Include="OpenTelemetry.Api" Version="1.4.0-rc.1" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry" Version="1.4.0-rc.1" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry.Exporter.Console" Version="1.4.0-rc.1" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.4.0-rc.1" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.4.0-rc.1" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.0.0-rc9.10" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.0.0-rc9.10" NoWarn="NU5104" />
	  <PackageReference Include="OpenTelemetry.Instrumentation.SqlClient" Version="1.0.0-rc9.10" NoWarn="NU5104" />	  
  </ItemGroup>

When running an ASP.NET NET6.0 App, an exception ocurrs:

System.TypeInitializationException
  HResult=0x80131534
  Message=The type initializer for 'OpenTelemetry.Sdk' threw an exception.
  Source=OpenTelemetry
  StackTrace:
   at OpenTelemetry.Sdk.get_SuppressInstrumentation()
   at Microsoft.Extensions.DependencyInjection.ProviderBuilderServiceCollectionExtensions.AddOpenTelemetrySharedProviderBuilderServices(IServiceCollection services)
   at OpenTelemetry.Trace.TracerProviderBuilderBase..ctor()
   at OpenTelemetry.Trace.TracerProviderBuilderHosting..ctor(IServiceCollection services)
   at Microsoft.Extensions.DependencyInjection.OpenTelemetryServicesExtensions.AddOpenTelemetryTracing(IServiceCollection services, Action`1 configure)
   at App.OpenTelemetry.OpenTelemetry.OpenTelemetryProvider.InstrumentAspNetCoreApplication(IServiceCollection services) in D:\DEV\git\DotNetClasses\dotnet\src\dotnetcore\Providers\OpenTelemetry\OpenTelemetry\OpenTelemetryProvider.cs:line 17
   at App.Services.OpenTelemetry.OpenTelemetryService.Setup(IServiceCollection services) in D:\DEV\git\DotNetClasses\dotnet\src\dotnetcore\GxClasses\Services\OpenTelemetry\OpenTelemetryService.cs:line 48
   at App.Application.Startup.ConfigureServices(IServiceCollection services) in D:\DEV\git\DotNetClasses\dotnet\src\dotnetcore\GxNetCoreStartup\Startup.cs:line 140
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Span`1& arguments, Signature sig, Boolean constructor, Boolean wrapExceptions)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at Microsoft.AspNetCore.Hosting.ConfigureServicesBuilder.InvokeCore(Object instance, IServiceCollection services)
   at Microsoft.AspNetCore.Hosting.ConfigureServicesBuilder.<>c__DisplayClass9_0.<Invoke>g__Startup|0(IServiceCollection serviceCollection)
   at Microsoft.AspNetCore.Hosting.StartupLoader.ConfigureServicesDelegateBuilder`1.<>c__DisplayClass15_0.<BuildStartupServicesFilterPipeline>g__RunPipeline|0(IServiceCollection services)
   at Microsoft.AspNetCore.Hosting.ConfigureServicesBuilder.Invoke(Object instance, IServiceCollection services)
   at Microsoft.AspNetCore.Hosting.ConfigureServicesBuilder.<>c__DisplayClass8_0.<Build>b__0(IServiceCollection services)
   at Microsoft.AspNetCore.Hosting.StartupLoader.ConfigureServicesDelegateBuilder`1.<>c__DisplayClass14_0.<ConfigureServices>g__ConfigureServicesWithContainerConfiguration|0(IServiceCollection services)
   at Microsoft.AspNetCore.Hosting.ConventionBasedStartup.ConfigureServices(IServiceCollection services)

  This exception was originally thrown at this call stack:
    [External Code]
    GxClasses.Helpers.AssemblyLoader.LoadContext_Resolving(System.Runtime.Loader.AssemblyLoadContext, System.Reflection.AssemblyName) in CompatibilityExtensions.cs
    [External Code]

Inner Exception 1:
FileLoadException: Could not load file or assembly 'System.Diagnostics.DiagnosticSource, Version=7.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. Could not find or load a specific file. (0x80131621)

It seems that DiagnosticSource is not compatible with .NET6?
Seems to be related to this Issue: Azure/azure-functions-host#8938

[alanwest]

@ggallotti Are you experiencing this with an azure function or is this just a regular asp.net core application?

[ggallotti]

Just a regular Asp.Net (Net6.0) Application. Downgraded to 1.4.0-alpha.1 with no Issues.

'System.Diagnostics.DiagnosticSource, Version=7.0.0.0' is resolved correctly by the PackageManager.

[alanwest]

It seems that DiagnosticSource is not compatible with .NET6?

DiagnosticSource 7.0 is compatible with .NET 6.

Using our example ASP.NET Core app, I'm not able to reproduce what you're seeing. The app is a .NET 6 application.

Do you have a minimal repro you can provide?

[ggallotti]

@alanwest, you are right. Just tested a minimal NET6 APP and it's working.
Seems some dependency Issue in my installation.
Sorry for the trouble and thank for your response.

[PiotrSzydloRelativity]

Same situation after adding OpenTelemetry 1.4.0-rc.2
'System.IO.FileNotFoundException: 'Could not load file or assembly 'System.Diagnostics.DiagnosticSource, Version=7.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified.''

[ceng-p]

+1 getting this as well - I'm running on a function though! What was the problem @ggallotti ?

Same situation after adding OpenTelemetry 1.4.0-rc.2 'System.IO.FileNotFoundException: 'Could not load file or assembly 'System.Diagnostics.DiagnosticSource, Version=7.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'. The system cannot find the file specified.''

[ggallotti]

I couldn't solve it. Tested the example app and it worked. So I assumed that it was something of my installation. I went back to old OTEL version where System.Diagnostics.DiagnosticSource v7 is not required.

However, seeing two more reports about this, makes me wonder if there is a real issue there.

[PiotrSzydloRelativity]

The stable version 1.3.2 worked for me

[ceng-p]

The stable version 1.3.2 worked for me

Yep, also went in and downgraded all packages that had Opentelemetry >= 1.4.0 as a dependency and got it working. According to the thread Azure/azure-functions-host#8938 Otel stuff in 1.4 is a RC right now, so perhaps it makes sense to not use those versions by default.

[martinjt]

Unfortunately azure functions that aren't using isolated mode will not work. This is because the function Runtime has a hard dependency on 6.0.0 of System.DiagnosticSource. it requires the Azure functions to fix, which I wouldn't expect to happen given they are trying to deprecate them.

I'm really looking for a reproduction of this. Obviously we can't ask people to post private projects, however, if you have a way to reproduce it that you're willing to share over a video call I'll happily make the time.

https://www.honeycomb.io/devrel/observability-office-hours

There is likely something funky in build processes or clients thar we need to get to the bottom of.

[cijothomas]

@martinjt the repro is pretty straightforward in Functions. One minimal repro is already shared in the linked issue.
I also found another user posting one : cijothomas/FunctionsOpenTelemetry#2