One logger for a multi-project solution

Question

I am integrating Serilog into an existing multi-class layer and Multi-Assembly Solution that I've created. The previous logging technique I used was simply passing a string up the layers with events. I'd like to get away from this.

I have read that I can use the app.config file to load the logger config into each class in my library but how can I do this in a multi-assembly project.

I have a top-level / startup project and two class library projects. I would like to use the same logger with two sinks for the whole program.

These are the articles I have found so far

https://github.com/serilog/serilog/wiki/AppSettings

http://nblumhardt.com/2014/04/xml-configuration-for-serilog/

Could someone explain how to accomplish this?

Answer 1

Serilog lets you use a logger configuration per program; though it's possible to adjust logging class-by-class this is usually done after the fact with filtering and so-on.

The recommended approach is:

Set up Serilog as the first thing in Program.Main() or wherever your app's entry point is:

Log.Logger = new LoggerConfiguration()
  .WriteTo.Sink1()
  .WriteTo.Sink2()
  .CreateLogger();

Notice this sets up the static Log class. Elsewhere in your app you can now write:

Log.Information("This is a message");

and the message will be passed to both sinks. You can avoid the static Log and instead pass ILogger around, but unless you have strong preferences here, the static option is less hassle.

XML/appSettings configuration doesn't change any of this. It just moves some details to the config file, so changing the first block of code to:

Log.Logger = new LoggerConfiguration()
  .ReadFrom.AppSettings()
  .CreateLogger();

And adding:

<add key="serilog:write-to:Sink1" />
<add key="serilog:write-to:Sink2" />

to App.config will have the same effect. Configuration in code is often less hassle (fewer moving parts) if you can avoid the XML.