Setting the MinimumLevel in Serilog: is it possible to use a wildcard/regex for the namespace?

Question

Setting the MinimumLevel in Serilog: is it possible to use wildcards/regex the namespace ?

Let's assume that I have my own namespaces with different casing, which need both to be logged on Information.

• MyNameSpace
• MYNameSpace

Can this be done via the configuration like this?

"SeriLog": {
    "MinimumLevel": {
      "Default": "Information",
      "Override": {
        "Default": "Warning",
        "MyNameSpace|MYNameSpace": "Information"
      }
    }
  }

Or is this only possible by specifying both?

"SeriLog": {
    "MinimumLevel": {
      "Default": "Information",
      "Override": {
        "Default": "Warning",
        "MyNameSpace": "Information",
        "MYNameSpace": "Information"
      }
    }
  }

Answer 1

The minimum level override feature does not support wildcards/regex as of this writing. It only supports simple (case-sensitive) partial matching. You can see how it works in the source code.

Declaring the two different namespaces as your second example is the way to go.

Answer 2

You can also exclude some log entries using Serilog.Expressions https://github.com/serilog/serilog/issues/1786#issuecomment-1487933383

I.e. set the minimum level for System.Net.Http.HttpClient to allow Information though, but use Filter.ByExcluding(...) and e.g. an expression to exclude SourceContext like 'System.Net.Http.HttpClient.%.LogicalHandler'.