Observability

Shared host helpers for JSON logs, HTTP correlation, and optional OpenTelemetry. Not a fourth suite “engine” — libraries the cores use so operators get the same shape everywhere.

Package	Role	Used by
OxyKit.Observability	JSON console logging + X-Correlation-Id	Render, Mail, Flow
OxyKit.OpenTelemetry	Optional OTLP traces + metrics (off by default)	Mail, Flow only

Repo: oxykit-dev/OxyKit.Observability · NuGet: OxyKit.Observability · OxyKit.OpenTelemetry

Render does not reference OxyKit.OpenTelemetry (thin sidecar / AOT-size). No Serilog or Sentry SDKs in the cores.

Correlation

Every host accepts or generates X-Correlation-Id, echoes it on the response, and includes it in log scopes.

Behavior	Detail
Inbound	Send X-Correlation-Id; omitted → host generates a value
Response	Same header always echoed
Flow jobs	Background work sets an ambient id and propagates it to Render and Mail HTTP

Logs

Outside Development (including Compose Production), hosts write JSON to stdout (docker compose logs). Force with Logging:JsonConsole / Logging__JsonConsole (true / false).

App code stays on ILogger<T> message templates — no Serilog façade.

Optional OpenTelemetry (Mail + Flow)

Off unless you opt in:

Enable with	Notes
OpenTelemetry:Enabled=true	Or OpenTelemetry__Enabled=true
OTEL_EXPORTER_OTLP_ENDPOINT	Standard OTel env; also enables export
OTEL_SERVICE_NAME	Optional override of OpenTelemetry:ServiceName

Exports OTLP traces + metrics (ASP.NET Core, HttpClient, runtime, plus product Activity/Meter names such as OxyKit.Mail / OxyKit.Flow). Logs stay on stdout JSON this wave.

Commented examples live in the suite-root .env.example compose env template.

Host wiring (integrators of the APIs)

Callers only need the correlation header for support. Host builders (or forkers) use:

builder.AddOxyKitJsonConsole();
app.UseOxyKitCorrelation();

// Mail / Flow only:
builder.AddOxyKitOpenTelemetry(o =>
{
    o.ServiceName = "OxyKit.Mail";
    o.ActivitySources = ["OxyKit.Mail"];
    o.Meters = ["OxyKit.Mail"];
});

See also Local compose and each product overview.