Custom instrumentation

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Custom Spans

Create manual RUM spans to instrument custom flows in your application. Requires traceParentInHeader.enabled: true.

Prerequisite:

await CoralogixRum.init({
  // ...
  traceParentInHeader: { enabled: true },
});

Basic usage — global span with a child:

import { CoralogixRum } from '@coralogix/react-native-plugin';

const tracer = CoralogixRum.getCustomTracer();

const globalSpan = await tracer.startGlobalSpan('checkout', { step: 'start' });
if (!globalSpan) return; // another global span is already active

const childSpan = await globalSpan.startCustomSpan('validate-cart');
await childSpan?.endSpan();

await globalSpan.endSpan();

Linking network requests with withContext:

When you call fetch inside withContext, the network request is automatically linked to the active global span's trace.

const globalSpan = await tracer.startGlobalSpan('checkout');

await globalSpan.withContext(async () => {
  await fetch('https://api.example.com/cart'); // linked to globalSpan's traceId
});

await globalSpan.endSpan();

ignoredInstruments — exclude auto-instrumentation from the trace:

Pass instrument names to prevent network requests, errors, or interactions fired during this tracer's spans from being linked to your custom trace.

const tracer = CoralogixRum.getCustomTracer(['networkRequests', 'userInteractions', 'errors']);

Note

Only one global span may be active at a time. startGlobalSpan returns null if a global span is already open.

Time Measurement

Measure the duration of arbitrary flows with a pair of startTimeMeasure(name, labels?) / endTimeMeasure(name) calls. The native SDK records start/end timestamps and reports the delta as a custom-measurement span (milliseconds).

import { CoralogixRum } from '@coralogix/react-native-plugin';

CoralogixRum.startTimeMeasure('checkout', { flow: 'checkout' });

await validateCart();
await charge();
await confirm();

CoralogixRum.endTimeMeasure('checkout');

Behaviour:

• Both calls are fire-and-forget — they cross the bridge directly into native and return immediately.
• The JS side keeps no state; the native SDK owns the in-flight registry.
• You are responsible for pairing every startTimeMeasure(name, labels?) with exactly one endTimeMeasure(name). Leaked starts persist in memory until CoralogixRum.shutdown().
• Unmatched endTimeMeasure calls are dropped silently by the native SDK.
• Calling startTimeMeasure again with an open name overwrites the previous start.