apm-agent-dotnet: Using Serilog with Elastic APM causes NullReferenceException

Describe the bug When using Serilog and Elastic APM together in Asp.Net COre, a NullReferenceException is thrown on start-up.

Versions: netcoreapp 2.1 Elastic.Apm.NetCoreAll 1.1.1 Serilog.AspnetCore 3.0.0

To Reproduce Steps to reproduce the behavior:

Clone this repo: https://github.com/scotmeiste/elastic-apm-serilog-error
in appsettings.json, replace ServerUrls and SecretToken with your instance of Elastic APM
Run Web Api project
See error in debug output (Debug Console tab in VS Code)

Elastic APM .NET Agent: [CRITICAL] Exception thrown by logging implementation. Log message: `The agent was started without a service name. The automatically discovered service name is {ServiceName}'. args.Length: 1. Current thread: managed ID: 1
Elastic APM .NET Agent: +-> Exception (exception): System.NullReferenceException: Object reference not set to an instance of an object.
Elastic APM .NET Agent:    at Serilog.Extensions.Logging.SerilogLogger.Log[TState](LogLevel logLevel, EventId eventId, TState state, Exception exception, Func`3 formatter)
   at Elastic.Apm.AspNetCore.AspNetCoreLogger.Log[TState](LogLevel level, TState state, Exception e, Func`3 formatter)
   at Elastic.Apm.Logging.LoggingExtensions.DoLog(IApmLogger logger, LogLevel level, String message, Exception e, Object[] args)e: <null>

Expected behavior Either no error, or a more helpful description of what went wrong.

About this issue

Original URL
State: closed
Created 5 years ago
Comments: 18 (10 by maintainers)

Most upvoted comments

@scotm-gxg: The patch with the fix is out: https://github.com/elastic/apm-agent-dotnet/releases/tag/1.1.2 - so 1.1.2 should be ok with Serilog. The packages are also updated on nuget.org.

gregkalapos on Oct 11, 2019

Alright, looks like its working now!

Thanks for posting that fork/PR. it helped a ton. And thanks for the assistance!

Any idea when this will get rolled into a release? No rush or anything, just want to make sure I update the fix on my main project.

Awesome!

Regarding release: we already have 2 fairly important fixes on master. We don’t make promises on release dates, but I think having those 2 fixes out there would be important, so I’m thinking about a patch release very soon.

gregkalapos on Oct 10, 2019

Alright, looks like its working now!

Thanks for posting that fork/PR. it helped a ton. And thanks for the assistance!

Any idea when this will get rolled into a release? No rush or anything, just want to make sure I update the fix on my main project.

scotm-gxg on Oct 10, 2019

@scotm-gxg thanks for the update. I’ll fork your repo and try myself.

gregkalapos on Oct 10, 2019

Glad that test project helped!

I tried building your PR locally, but I got the error again. its near the end of my day here, so I will check it again in the morning to see if I got the right branch and built it correctly and all that.

Thanks again for your help!

scotm-gxg on Oct 9, 2019

As it seems, all our structured logs with serilog throw an exception.

Already something like this ends up with a NullReferenceException:

_logger?.Info()?.Log("Log {param}.", "abc");

gregkalapos on Oct 9, 2019