How to implement DiagnosticSource & Activity in .NET core?

HttpClient on .NET Core should be a good example. 

 

https://github.com/dotnet/corefx/blob/master/src/System.Net.Http/src/System/Net/Http/DiagnosticsHandler.cs

 

There is also guidance https://github.com/Microsoft/ApplicationInsights-dotnet-server/blob/b3a1d3ade8d5d1ccf8d1b0b922764a97b88ab96c/LibraryInstrumentationGuidance.md (it's work in progress).

 

Hope it helps,

Liudmila