configure-logging

name	configure-logging
description	ABP startup, runtime, exception logging, and the startup-template Serilog bridge. USE FOR: typed ILogger in ABP services; IInitLoggerFactory/GetInitLogger startup buffering; ABP exceptions via LogException; Serilog via UseSerilog. DO NOT USE FOR: audit-log persistence and entity history (configure-audit-logging); distributed traces and metrics (out of scope, wire the OpenTelemetry .NET SDK directly); exception-to-HTTP response details (handle-validation-and-errors).
license	MIT

Configuring Logging in ABP

When to Use

• Configure a logging provider for an ABP host.
• Log from application services through ILogger<T>.
• Understand logs emitted before the final service provider exists.
• Preserve ABP exception log levels, error metadata, and self-logging behavior.
• Follow the startup-template Serilog pattern.

When Not to Use

• Audit log persistence, contributors, or entity change history — use configure-audit-logging.
• Tracing, metrics, exporters, or telemetry sampling — out of scope here; ABP ships no OpenTelemetry framework module, so wire the OpenTelemetry .NET SDK directly.
• HTTP exception response mapping or client-visible details — use handle-validation-and-errors.

How it works

ABP does not replace Microsoft.Extensions.Logging. Register providers through the standard .NET host and inject ILogger<T> into services.

public class ReportGenerator : ITransientDependency
{
    private readonly ILogger<ReportGenerator> _logger;

    public ReportGenerator(ILogger<ReportGenerator> logger)
    {
        _logger = logger;
    }

    public void Generate()
    {
        _logger.LogInformation("Generating report");
    }
}

Early initialization logs

ABP registers IInitLoggerFactory before normal module registration. IServiceCollection.GetInitLogger<T>() returns a buffered initialization logger from that factory, or NullLogger<T>.Instance if the factory is unavailable. DefaultInitLoggerFactory caches loggers by category and retains AbpInitLogEntry items until application initialization transfers them to the configured ILoggerFactory and clears them.

Use this only in infrastructure that must log while services are still being registered:

var logger = context.Services.GetInitLogger<MyAppModule>();
logger.LogDebug("Configuring module services");

No IObjectAccessor<ILogger>-based early logging registration exists in the ABP framework source. Do not document or add that older/unverified pattern.

Exception logging

Use ABP's ILogger.LogException(exception, optionalLevel) extension when logging an ABP exception outside the automatic exception pipeline. Without an explicit level it calls exception.GetLogLevel(); the default is Error, while BusinessException defaults to Warning through IHasLogLevel.

LogException also logs known IHasErrorCode/IHasErrorDetails properties, invokes IExceptionWithSelfLogging.Log(ILogger), and logs exception Data. Avoid following it with another LogError for the same exception.

ASP.NET Core exception middleware calls LogException unless an AbpExceptionHandlingOptions.ExcludeExceptionFromLoggerSelectors predicate excludes the exception.

Serilog startup-template bridge

The application template creates the static bootstrap logger before building the host, then bridges the host to Serilog:

Log.Logger = new LoggerConfiguration()
#if DEBUG
    .MinimumLevel.Debug()
#else
    .MinimumLevel.Information()
#endif
    .MinimumLevel.Override("Microsoft", LogEventLevel.Information)
    .MinimumLevel.Override("Microsoft.EntityFrameworkCore", LogEventLevel.Warning)
    .Enrich.FromLogContext()
    .WriteTo.Async(c => c.File("Logs/logs.txt"))
    .WriteTo.Async(c => c.Console())
    .CreateLogger();

try
{
    var builder = WebApplication.CreateBuilder(args);
    builder.Host.UseSerilog();
    await builder.AddApplicationAsync<MyAppModule>();
    var app = builder.Build();
    await app.InitializeApplicationAsync();
    await app.RunAsync();
}
catch (Exception exception)
{
    // The template rethrows HostAbortedException (e.g. from `dotnet ef`) instead of logging it as fatal.
    if (exception is HostAbortedException)
    {
        throw;
    }

    Log.Fatal(exception, "Host terminated unexpectedly!");
}
finally
{
    Log.CloseAndFlush();
}

The template uses .MinimumLevel.Debug() in DEBUG builds and .MinimumLevel.Information() otherwise, and rethrows HostAbortedException rather than logging it as fatal.

Keep provider-specific configuration in the host. Application and module code should normally depend on ILogger<T>, not Serilog's static Log API.

Validation

• Start the application and confirm both early module logs and runtime ILogger<T> logs reach the configured sink.
• Throw a test BusinessException and verify automatic logging uses Warning unless explicitly changed.
• Test an IExceptionWithSelfLogging exception and verify its additional log is emitted once.
• Confirm UseSerilog() is called before AddApplicationAsync/host build.
• Shut down the host and verify buffered sinks are flushed.

Common Pitfalls

• Looking for IObjectAccessor<ILogger> — early logging uses IInitLoggerFactory and GetInitLogger<T>().
• Treating audit logging as application logging — audit records have a separate pipeline and storage model.
• Double-logging handled exceptions — ABP's exception middleware already logs caught exceptions.
• Injecting Serilog types throughout application code — prefer ILogger<T> so provider choice stays at the host boundary.
• Creating the bootstrap logger after host construction — startup failures before that point will not reach it.
• Forgetting Log.CloseAndFlush() — asynchronous/file sinks can retain buffered events.