Consent manager

If your website uses a consent manager (also called cookie banner or CMP), ABlyft must know what the visitor has agreed to. ABlyft supports this with two rules in your project and two API calls that you trigger from your consent manager.

Choose a setupCopy Anchor Link

Technically, ABlyft can work with a consent management platform (CMP) in three ways. Which one fits depends on your architecture, your testing setup and your data protection requirements. Assess the legal side independently of what is technically possible.

1. Independent of consent. The snippet runs without restrictions and is not linked to the CMP. Leave both rules below at their default return true;.

2. Load after consent. The snippet is blocked by your CMP and loaded once the visitor agreed. Until then ABlyft does not run at all. This is simple, but visitors may see flicker, because variations can only be applied after the decision.

3. Consent-dependent storage and tracking. The snippet sits directly in the page and runs before consent, so variations appear without flicker. Storage and tracking wait for the visitor's decision. This is the setup described in the rest of this page.

How it worksCopy Anchor Link

ABlyft separates two things:

You can always show variations, and only track once the visitor consented. This avoids flicker, because the snippet can stay in the <head> of your page.

While the tracking rule does not return true:

• Data that ABlyft would write to the browser (for example the variation assignment) is kept in memory only.
• Events that would be sent (bucketing, goals) are held back in the browser's sessionStorage key ablyft_temp_events.
• The consent state itself (ablyft_tracking_consent) and a redirect marker are still stored, because they are needed to remember the decision.

As soon as consent is given, the held data is moved to the configured storage and the events are sent.

Step 1: Set the rules in ABlyftCopy Anchor Link

1. Open your project and go to Settings → Prerequisites ("Project Prerequisites").
2. Edit the two code fields. Each is the body of a JavaScript function. Return true to allow the stage.

An empty rule counts as true. If your code throws an error, the error is logged and the rule counts as not met.

Example: always show variations, and track only after consent. These are the examples shown on the Prerequisites page.

Show Variations (General Startup)

if (ablyft.get('trackingConsentEnabled') !== false) {
  return true;
}

Start Tracking (and Browser Storage)

return ablyft.get('trackingConsentEnabled');

ablyft.get('trackingConsentEnabled') returns true after enableTrackingConsent, false after disableTrackingConsent, and an empty value as long as the visitor has not decided yet. That is why the first rule uses !== false: variations are shown until the visitor explicitly declines.

If you return false from Show Variations, ABlyft does not run experiments on that page view.

Step 2: Tell ABlyft about the decisionCopy Anchor Link

Call these from the consent callback of your consent manager. The calls also work before the snippet has loaded.

window.ablyft = window.ablyft || [];

// Visitor accepted
window.ablyft.push({ eventType: 'enableTrackingConsent' });

// Visitor declined
window.ablyft.push({ eventType: 'disableTrackingConsent' });

See enableTrackingConsent and disableTrackingConsent for what each call does.

Example with a generic consent managerCopy Anchor Link

Most consent managers can run JavaScript when the visitor accepts or declines, or provide a status you can read. The exact API differs for each product, so the names onConsentChange and hasStatisticsConsent below are placeholders for the functions of your consent manager.

<script>
  window.ablyft = window.ablyft || [];

  function syncAblyftConsent(hasConsent) {
    window.ablyft.push({
      eventType: hasConsent ? 'enableTrackingConsent' : 'disableTrackingConsent',
    });
  }

  // 1. Remember the decision of returning visitors
  if (typeof hasStatisticsConsent === 'function' && hasStatisticsConsent()) {
    syncAblyftConsent(true);
  }

  // 2. React when the visitor decides
  if (typeof onConsentChange === 'function') {
    onConsentChange(function (consent) {
      syncAblyftConsent(consent.statistics === true);
    });
  }
</script>

Check that it worksCopy Anchor Link

1. Open your site in a private window without giving consent.
2. In the console, run ablyft.get('trackingConsentEnabled'). It returns an empty value.
3. Accept in your consent manager and run it again. It returns true.
4. Turn on debug mode. The console then shows whether the general and tracking prerequisite rules are met.

Next stepsCopy Anchor Link