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Sentori

init.beforeSend hook

init({ beforeSend }) is the SDK’s escape hatch for host-side PII scrubbing the SDK can’t do automatically. Sentori already strips a fixed set of suspicious fields (raw email, phone, ip_address) and the server’s privacy_lab catches anything the ingest path missed — but every host has its own custom fields (employeeId, internalCaseRef, customer_pii.full_name) that only the host knows to redact.

sentori.init({
  token: 'st_pk_…',
  release: 'myapp@1.0.0',
  beforeSend(event) {
    // Drop entirely.
    if (event.tags?.flow === 'kyc') return null


    // Mutate + ship.
    return {
      ...event,
      tags: {
        ...event.tags,
        company_size_bucket: bucketise(event.tags?.company_size),
      },
    }
  },
})

Signature

Section titled “Signature”
type BeforeSendHook = (event: Event) => Event | null
  • Return the event (possibly mutated, possibly same reference) to send it.
  • Return null to drop it. No transport, no breadcrumb-of-drop.
  • Synchronous. Async pre-send mutation is deliberately not supported — that would let a buggy host stall the SDK’s hot path.

NEVER-rule fallback

Section titled “NEVER-rule fallback”

Both captureException and captureMessage invoke beforeSend inside a try/catch:

  • If the hook throws, the SDK swallows the error, emits one one-shot logger.warn, and falls back to the unmodified event.
  • If the hook returns a non-event (e.g. undefined, 42, another object without an id), same fallback policy.

A buggy beforeSend cannot stall, drop-by-mistake, or break the capture pipeline.

Common patterns

Section titled “Common patterns”

Strip a host-specific PII tag

Section titled “Strip a host-specific PII tag”
beforeSend(event) {
  if (event.tags?.employeeId) {
    const { employeeId, ...safeTags } = event.tags
    return { ...event, tags: safeTags }
  }
  return event
}

Drop events from internal QA users

Section titled “Drop events from internal QA users”
beforeSend(event) {
  if (event.user?.id?.startsWith('qa-')) return null
  return event
}

Coerce a high-cardinality field to a bucket

Section titled “Coerce a high-cardinality field to a bucket”
beforeSend(event) {
  const raw = event.tags?.['db.duration_ms']
  if (raw === undefined) return event
  const n = Number(raw)
  return {
    ...event,
    tags: {
      ...event.tags,
      'db.duration_bucket': n < 50 ? 'fast' : n < 500 ? 'mid' : 'slow',
    },
  }
}

What beforeSend is NOT

Section titled “What beforeSend is NOT”
  • Not a transport replacement. The hook can drop or mutate, but it can’t redirect the event to a different endpoint. Use init.ingestUrl for self-hosted Sentori.
  • Not a sampling knob. Use init.sample.errors / init.sample.traces / init.sample.messages for that — they decide before the event is built, which is cheaper than building + dropping.
  • Not for breadcrumb scrubbing. Breadcrumbs are inside event.breadcrumbs — you can mutate that array — but for scrubbing the breadcrumb stream itself, host’s sentori.addBreadcrumb call sites are where the original data lives. Wrap at that site if you want.

Sentry-compat note

Section titled “Sentry-compat note”

The Sentry-compat sub-package (@goliapkg/sentori-react-native/compat) refuses to support the full Sentry beforeSend signature shape (it accepts a Hint parameter, async returns, and the rest of the historical contract). Sentry-compat hosts who pass Sentry.init({ beforeSend }) get a one-shot info hint pointing them at this page — call sentori.init({ beforeSend }) directly instead.

Section titled “Related”