Cannot set minimum logging level to warning for HttpClients using Serilog

Question

I am trying to set Serilog's minimum level of calls using HttpClient to warning in a .Net 5 Blazor application using Serilog 2.10.0. It seems to work EFCore and other components but not HTTPClient - and I get info level quite verbose logging every time an HttpClient call is made.

The code in my Program.cs file looks like this.

 public static void Main(string[] args)
    {
        // see https://nblumhardt.com/2019/10/serilog-in-aspnetcore-3/
        Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Override("Microsoft.AspNetCore", LogEventLevel.Warning)
            .MinimumLevel.Override("Microsoft.EntityFrameworkCore", LogEventLevel.Warning)
            .MinimumLevel.Override("System", LogEventLevel.Warning)
            .MinimumLevel.Override("System.Net.Http.HttpClient", LogEventLevel.Warning)
            .Enrich.FromLogContext()
            .WriteTo.File(new CompactJsonFormatter(), "Logs/log-.clef", rollingInterval: RollingInterval.Day)
            .WriteTo.Console()
            .CreateLogger();

Any suggestions on how to fix this would be greatly appreciated.

Answer 1

This is a bug, fixed in version 4.0.0, see:

https://github.com/serilog/serilog-aspnetcore/issues/221

An alternative is to use the ILogEventFilter:

public class MyLoggingFilter : ILogEventFilter
{
    private static readonly HashSet<string> ignoredMessages = new HashSet<string>(StringComparer.Ordinal)
    {
        "Start processing HTTP request {HttpMethod} {Uri}",
        "End processing HTTP request after {ElapsedMilliseconds}ms - {StatusCode}"
    };

    // Allow the event to be logged if the message template isn't one we ignore
    public bool IsEnabled(LogEvent logEvent) => !ignoredMessages.Contains(logEvent.MessageTemplate.Text);
}

and:

Log.Logger = new LoggerConfiguration()
    .MinimumLevel.Override("Microsoft.AspNetCore", LogEventLevel.Warning)
    .MinimumLevel.Override("Microsoft.EntityFrameworkCore", LogEventLevel.Warning)
    .MinimumLevel.Override("System", LogEventLevel.Warning)
    .Filter.With<MyLoggingFilter>() // <-- Plug in your filter type
    .Enrich.FromLogContext()
    .WriteTo.File(new CompactJsonFormatter(), "Logs/log-.clef", rollingInterval: RollingInterval.Day)
    .WriteTo.Console()
    .CreateLogger();