Function initTelemetry

packages/server/src/telemetry.ts:43–132

(opts: InitTelemetryOptions = {})

}

export function initTelemetry(opts: InitTelemetryOptions = {}): { tracer: Tracer; meter: Meter } {
  const fileSinkEnabled = opts.localSink !== undefined;
  const pushEnabled = process.env.OTEL_SDK_DISABLED === 'false';

  if (!fileSinkEnabled && !pushEnabled) {
    return noopResult();
  }

  if (tracerProvider) {
    return noopResult();
  }

  try {
    const resource = resourceFromAttributes({
      [ATTR_SERVICE_NAME]: process.env.OTEL_SERVICE_NAME || 'open-knowledge-server',
      [ATTR_SERVICE_VERSION]: process.env.OTEL_SERVICE_VERSION || '0.2.0',
    });

    const contextManager = new AsyncLocalStorageContextManager();
    context.setGlobalContextManager(contextManager);

    const spanProcessors: SpanProcessor[] = [];
    const attributeDenylist =
      opts.localSink?.attributeDenylist ?? DEFAULT_TELEMETRY_ATTRIBUTE_DENYLIST;
    spanProcessors.push(new ScrubbingSpanProcessor({ attributeDenylist }));
    if (fileSinkEnabled && opts.localSink !== undefined) {
      fileSpanExporter = new FileSpanExporter({
        projectDir: opts.localSink.projectDir,
        maxBytes: opts.localSink.spansMaxBytes,
      });
      spanProcessors.push(new SimpleSpanProcessor(fileSpanExporter));
    }
    if (pushEnabled) {
      spanProcessors.push(new BatchSpanProcessor(new OTLPTraceExporter()));
    }

    const tp = new BasicTracerProvider({ resource, spanProcessors });
    trace.setGlobalTracerProvider(tp);
    tracerProvider = tp;

    try {
      propagation.setGlobalPropagator(new W3CTraceContextPropagator());
    } catch (e) {
      const log = getLogger('telemetry');
      log.warn(
        { err: e },
        'OpenTelemetry propagator init failed — file sink active, distributed trace correlation degraded',
      );
    }

    let mp: MeterProvider | null = null;
    if (pushEnabled) {
      const metricExporter = new OTLPMetricExporter();
      mp = new MeterProvider({
        resource,
        readers: [new PeriodicExportingMetricReader({ exporter: metricExporter })],
      });
      metrics.setGlobalMeterProvider(mp);