Redirector page, redux

A long way back, you learned that direct links to static assets (like, say, a PDF) won’t be tracked by Munchkin. You should instead have a central Redirector LP that hooks up the Munchkin cookie before flipping to the target asset.

Later, I showed how to instrument Munchkin so an event fires as soon as Visit Web Page has been logged, allowing the fastest response for Munchkin-dependent stuff — like redirecting.

Hadn’t yet wrapped together those 2 concepts, though. So here’s how you should set up the Redirector LP in the modern age (as of late 2024).

First, download the HitEvent JS from my CDN and re-upload it to your Design Studio:

teknkl-munchkinhitevent-v1.js

Load that file in the <head> of your Redirector LP:

<!-- Munchkin event enabler -->
<script src="https://pages.example.com/rs/123-ABC-456/teknkl-munchkinhitevent-v1.js"></script>
<!-- /Munchkin event enabler -->

It’s critical that it load before the Munchkin library, which gets automatically injected at the end of the </body>, so the safe way is to put it in <head>.

Then use this JS instead of the original redirector JS:

redirect: {
   const allowedOrigins = [ // which domains are allowed for redirection
      "https://pages.example.com",
      "https://www.example.com",
      "https://example.com"
   ]; 
         
   const errNoAsset = "Asset URL not found."; // message when no asset in hash
   const errInvalidAsset = "Asset URL not allowed."; // when asset not our domain
   const redirectMs = 2000;
   
   let assetURL;
   try {
     assetURL = new URL(decodeURIComponent(document.location.hash.substring(1)));
   } catch(e){
     document.body.append(errNoAsset);
     break redirect;      
   }
      
   if(!allowedOrigins.includes(assetURL.origin)){
     document.body.append(errInvalidAsset);
     break redirect;
   }
   
   enableMunchkinHitEvent({ forceAfter: redirectMs, debug: true });
   
   document.addEventListener("munchkin.visitWebPage", function(e){
     document.location.href = assetURL.href;
   });
}

The JS is less clunky now as browsers do a lot more stuff natively than they did back in 2017 (!!).