Prevent Serilog from writing HTTP events by default

Question

I'm injecting typed HTTP clients in a .NET Core app. I'm also logging with Serilog. I have not intentionally configured any logging of HTTP activity. It magically came with. How do I turn this off?

[12:00:52 INF] Start processing HTTP request POST https://foo/bar
[12:00:52 INF] Sending HTTP request POST https://foo/bar
[12:00:53 INF] Received HTTP response after 707.8906ms - OK

My HTTP client configuration:

services.AddHttpClient("FOO")
    .ConfigureHttpClient(client =>
        {
            client.BaseAddress = new Uri("https://foo/");
        })
    .ConfigurePrimaryHttpMessageHandler(sp => new HttpClientHandler()
        {
            Credentials = new NetworkCredential("user", "pass"),
            ServerCertificateCustomValidationCallback = (senderC, cert, chain, sslPolicyErrors) => true
        })
    .AddTypedClient<Thing1>()
    .AddTypedClient<Thing2>();

Ventriloquy

Do you have a SerilogTraceListener active sucking all output made using System.Diagnostics.Trace into serilog? – Epididymis

@BenVoigt I did not explicitly set that up, so... maybe? – Ventriloquy

Answer 1

I ran into this and was able to address using Serilog's Filter configuration. Not sure where documented (this appears to be related), but one avenue is to implement the ILogEventFilter interface (source). Include logic for allowing an event, and plug into configuration.

Example filter class:

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);
}

Added to configuration (Program.cs in this case):

config
    .MinimumLevel.Override("Microsoft.AspNetCore", LogEventLevel.Warning)
    .Enrich.FromLogContext()
    .Filter.With<MyLoggingFilter>() // <-- Plug in your filter type
    .WriteTo.Console(theme: AnsiConsoleTheme.Code)
    .WriteTo.Debug()
    // etc

Alternatively, if you want to prevent any logging related to HttpClient, override the category (which is the type namespace) with desired log level:

config.MinimumLevel.Override("System.Net.Http.HttpClient", LogEventLevel.Warning) 

Alum

That seems like a band-aid. I'm still hoping for a solution that prevents HttpClient from logging all this junk in the first place. – Ventriloquy

Fair point, I wanted to receive part of them but not all. I updated the answer with the override method to prevent any logs from HttpClient. – Alum

I also learned that HttpClient only spams the log when ASPNETCORE_ENVIRONMENT is "Development". Still unexpected and annoying. – Ventriloquy

That's good to know, I will have to see about logging in production. – Alum

@PatrickSzalapski I used the second part of this answer, setting the minimum level for System.Net.Http.HttpClient. – Ventriloquy

Answer 2

Another option is to add an override for System.Net.Http.HttpClient to appsettings.json:

Leaden

Answer 3

This can be achieved by adding the following piece of lines in the app settings as well :

"Logging": {
  "LogLevel": {
    "Default": "Warning",
    "System.Net.Http.HttpClient": "None"
  }
}

Prevocalic