Syntrony.Logging.OpenTelemetry 1.1.0

Syntrony.Logging.OpenTelemetry

Backend-agnostic telemetry (logs, traces, metrics) for Syntrony.Logging, via OpenTelemetry with OTLP export. Not tied to any specific backend — Aspire Dashboard, Azure Application Insights (native OTLP endpoint), or any other OTLP-compatible collector are equally valid; the consuming application decides where to export.

builder.Services.AddSyntrony(options =>
{
    options.UseLogging(log => log
        .UseLog4Net()
        .UseOpenTelemetry(otel =>
        {
            otel.ServiceName    = "my-service";
            otel.ServiceVersion = typeof(Program).Assembly.GetName().Version?.ToString();
            otel.Endpoint       = builder.Configuration["Telemetry:OtlpEndpoint"];
        }));
});

UseOpenTelemetry(this ISyntronyLoggingBuilder, Action<SyntronyTelemetryOptions> configure, double? traceSampleRatio = null)

Never claims the structured-sink slot (RegisterStructuredSink) — composes freely with UseLog4Net() or whichever structured sink is active, since telemetry and structured logging aren't mutually exclusive.

SyntronyTelemetryOptions:

traceSampleRatio (default 1.0, i.e. 100%) sets the ParentBasedSampler(TraceIdRatioBasedSampler(...)) used for traces — pass a lower value in production to control cost; the default does not vary by environment on its own.

Default instrumentation, added automatically when traces or metrics are enabled: ASP.NET Core and HttpClient (query strings stripped from span attributes). Entity Framework Core instrumentation isn't bundled — its NuGet package (OpenTelemetry.Instrumentation.EntityFrameworkCore) has never shipped a stable release, which broke dotnet pack (NU5104, a stable package can't depend on a prerelease one). Add it yourself via ConfigureTracing if you need it:

otel.ConfigureTracing = tracing => tracing.AddEntityFrameworkCoreInstrumentation();

Dependency on ASP.NET Core's shared framework

OpenTelemetry.Instrumentation.AspNetCore declares a FrameworkReference to Microsoft.AspNetCore.App, and that propagates transitively to this package and to whoever installs it — a worker or console app that only wants OTLP export (traces/metrics/logs without the ASP.NET Core instrumentation) can't use this package as-is. Accepted as a deliberate exception: the real consumer of Syntrony.Logging.OpenTelemetry today is a web service. If a non-web consumer shows up, the escape hatch is to fork this package without OpenTelemetry.Instrumentation.AspNetCore — everything else here has no FrameworkReference.