Callbacks

Callbacks let you run custom code at key points in the consent lifecycle. Define them in the provider's callbacks option, or register them dynamically via useConsentManager().

Configuration

Define callbacks in the runtime options:

import { getOrCreateConsentRuntime } from 'c15t';

const { consentStore } = getOrCreateConsentRuntime({
  mode: 'c15t',
  backendURL: 'https://your-instance.c15t.dev',
  callbacks: {
    onBannerFetched: ({ jurisdiction, location, translations }) => {
      console.log('Jurisdiction:', jurisdiction);
      console.log('Country:', location.countryCode);
      console.log('Language:', translations.language);
    },
    onConsentSet: ({ preferences }) => {
      // Fire analytics event
      analytics.track('consent_updated', { preferences });
    },
    onError: ({ error }) => {
      errorReporter.captureMessage(error);
    },
    onBeforeConsentRevocationReload: ({ preferences }) => {
      // Flush pending analytics before page reloads
      analytics.flush();
    },
  },
});

Available Callbacks

`onBannerFetched`

Called when the consent banner data is fetched from the backend (or loaded from SSR data). The payload includes jurisdiction info, location data, and resolved translations.

onBannerFetched: ({ jurisdiction, location, translations }) => {
  // jurisdiction: 'GDPR' | 'CCPA' | { code: 'GDPR', message: '...' } | ...
  // location: { countryCode: 'DE', regionCode: 'BY' }
  // translations: { language: 'de', translations: {...} }
};

`onConsentSet`

Called whenever consent preferences are saved - whether by user action (saveConsents()), automatic defaults, or on initialization when no jurisdiction is detected.

onConsentSet: ({ preferences }) => {
  // preferences: { necessary: true, measurement: true, marketing: false, ... }
  if (preferences.measurement) {
    loadAnalytics();
  }
};

`onError`

Called when an error occurs during consent operations (e.g., API request failure). If no onError callback is provided, errors are logged to console.error.

onError: ({ error }) => {
  // error: string describing what went wrong
  Sentry.captureMessage(`Consent error: ${error}`);
};

`onBeforeConsentRevocationReload`

Called synchronously before the page reloads due to consent revocation. This is your last chance to run cleanup before the reload. Keep this callback fast - avoid async operations.

onBeforeConsentRevocationReload: ({ preferences }) => {
  // Flush any pending data
  navigator.sendBeacon('/api/flush', JSON.stringify({ session: sessionId }));
};

Dynamic Registration

const state = consentStore.getState();

// Register a callback
state.setCallback('onConsentSet', ({ preferences }) => {
  analytics.track('consent_changed', preferences);
});

// Remove a callback
state.setCallback('onConsentSet', undefined);