[BUG] APM agent not working on .NET 7

[christallire]

APM Agent version

The version of the Elastic.Apm nuget package used
https://github.com/elastic/apm-agent-dotnet/releases/download/v1.16.0/ElasticApmAgent_1.16.0.zip

Environment

Operating system and version:
Ubuntu focal arm64v8

.NET Framework/Core name and version (e.g. .NET 4.6.1, NET Core 3.1.100) :
.NET 7

Application Target Framework(s) (e.g. net461, netcoreapp3.1):
net7.0

Describe the bug

# kubectl logs -f backoffice-657d64b495-n849r app
Unhandled exception. System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation.
 ---> System.NullReferenceException: Object reference not set to an instance of an object.
   at StartupHook.InvokerLoaderMethod(Assembly loaderAssembly) in C:\Users\jenkins\workspace\net_apm-agent-dotnet-mbp_PR-1727\apm-agent-dotnet\src\ElasticApmAgentStartupHook\StartupHook.cs:line 179
   at StartupHook.Initialize() in C:\Users\jenkins\workspace\net_apm-agent-dotnet-mbp_PR-1727\apm-agent-dotnet\src\ElasticApmAgentStartupHook\StartupHook.cs:line 118
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
   at System.Reflection.MethodInvoker.Invoke(Object obj, IntPtr* args, BindingFlags invokeAttr)
   --- End of inner exception stack trace ---
   at System.Reflection.MethodInvoker.Invoke(Object obj, IntPtr* args, BindingFlags invokeAttr)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.StartupHookProvider.CallStartupHook(StartupHookNameOrPath startupHook)
   at System.StartupHookProvider.ProcessStartupHooks()

To Reproduce

Steps to reproduce the behavior:

1. Create a docker container with ENV DOTNET_STARTUP_HOOKS=/app/ElasticApmAgentStartupHook.dll
2. Run
3. Profit

Expected behavior

Container should run

Actual behavior

Container failed to run at start up

[z1c0]

Hi @christallire,
thanks for reporting this issue.
We will be looking into it at our earliest convenience and make sure .NET 7.0 is fully supported.

[z1c0]

Hi again @christallire,
we are still working on .NET 7 support (see also #1903) and it should be included in the next release.
The release that contains .NET 7 support should also resolve this issue.
Thanks for your patience.

[z1c0]

Hi @christallire,
the issue has been fixed and will be included in the upcoming release of the APM agent.
Thanks again for reaching out!