NullReferenceException ApmErrorLogger/GenerateApmStackTrace

[aheubusch]

APM Agent version

Elastic.Apm 1.9.0
Elastic.Apm.Extensions.Hosting 1.9.0
Elastic.Apm.Extensions.Logging 1.9.0

Environment

.NET Core 3.1

Describe the bug

ApmErrorLogger passes a null logger to StacktraceHelper.GenerateApmStackTrace (second arg)

apm-agent-dotnet/src/Elastic.Apm.Extensions.Logging/ApmErrorLogger.cs

Lines 45 to 46 in 4591f02

	errorLog.StackTrace = StacktraceHelper.GenerateApmStackTrace(exception, null, "CaptureErrorLogsAsApmError",
	apmAgent.ConfigurationReader, apmAgent.Components.ApmServerInfo);

which then causes a NullReferenceException. Several try/catch keep the exception from reaching user code though.

apm-agent-dotnet/src/Elastic.Apm/Helpers/StacktraceHelper.cs

Line 51 in 4591f02

logger.Trace()?.Log("transform stack frames");

To Reproduce

public static void Main()
{
    var host = Host
        .CreateDefaultBuilder()
        .ConfigureLogging(logging => logging.ClearProviders())
        .UseElasticApm()
        .Build();

    var logger = (ILogger)host.Services.GetService(typeof(ILogger<object>));
    logger.LogError(new Exception(), "error log with exception");
}

[gregkalapos]

😱

Thanks for reporting it - super useful summary 👍

Opened #1311 to fix it.