add plugin to track UTM parameters

Author: dannyvankooten

code-snippets/event-snippets/track-utm-parameters.php

@@ -0,0 +1,28 @@
+<?php
+
+/**
+* Plugin Name: Koko Analytics: Track UTM Parameters
+*
+* Requires 3 events named "UTM Source", "UTM Medium" and "UTM Campaign"
+*/
+
+add_action('wp_footer', function () {
+    ?><script>
+window.addEventListener('load', function() {
+    let map = {
+        'utm_source': 'UTM Source',
+        'utm_medium': 'UTM Medium',
+        'utm_campaign': 'UTM Campaign',
+    };
+
+    let queryParams = new URLSearchParams(window.location.search);
+    let hashParams = new URLSearchParams(window.location.hash.substring(1));
+    for (let [p, eventName] of Object.entries(map)) {
+        let value = queryParams.get(p) ?? hashParams.get(p);
+        if (value) {
+          window.koko_analytics.trackEvent(eventName, value);
+        }
+    }
+});
+</script><?php
+});