How to send events when user consents and stop when user revokes consent?

[okabak123]

I'm trying to start/stop sending events when user consents. There is a privacy banner on the page (using iubenda) and it basically takes a callback in its config like so:

  _iub.csConfiguration = {
    // ...
    callback: {
      onPreferenceExpressed: function () {
        if (_iub.cs.api.cs.consent.purposes["4"]) {
          console.log("user consented to monitoring");
          // TODO: activate Sentry

        }
        if (!_iub.cs.api.cs.consent.purposes["4"]) {
          console.log("user revoked consent of monitoring");
          // TODO: deactivate Sentry

        }
      },
    },
  };

I'm using the loader script and sentryOnLoad before the script. I've gotten this far:

window.sentryOnLoad = function () {
    Sentry.init({
      release: "",
      enabled: false,
    });
  };

This successfully stops Sentry from sending events however I don't understand how I could do enabled: true after init. Or even if this is the right way of doing it?

Any guidance is appreciated!

[lforst]

you could either add an event processor (recommended) or have a condition in beforeSend and beforeSendTransaction like so:

Sentry.addEventProcessor((event) => {
  if (!userHasGivenConsent) {
    return null;
  }
  
  return event;
})

That way, all events are dropped unless the user has given consent.

[gabrielwallin]

This suggestion looks nice! @lforst
If I wanted this to only target client events, would it be appropriate to handle that logic inside of the eventProcessor? For example like this:

Sentry.addEventProcessor((event) => {
  if (!userHasGivenConsent && typeof window !== 'undefined') {
    return null;
  }
  
  return event;
})

Or is there a better way of splitting this logic?

[lforst]

yup that works