docs: send primary conversion events to the first-party conversion worker

docs-src/src/components/trigger-event.tsx

@@ -11,6 +11,101 @@ export type RedditEventType =
     | 'Lead'
     | 'Purchase';
 
+const CONVERSION_WORKER_URL = 'https://rxdb-events.daniel-meyer-e90.workers.dev';
+/**
+ * Written by storeAdClickId() in Root.tsx when the user lands with a
+ * gclid/gbraid/wbraid URL param. Shape: { k, v, t }.
+ */
+export const AD_CLICK_STORAGE_ID = 'click_id';
+
+function getStoredAdClickId(): { k: string; v: string; t: number; } | null {
+    try {
+        const raw = localStorage.getItem(AD_CLICK_STORAGE_ID);
+        if (!raw) {
+            return null;
+        }
+        const parsed = JSON.parse(raw);
+        if (!parsed || !parsed.v) {
+            return null;
+        }
+        return parsed;
+    } catch (err) {
+        return null;
+    }
+}
+
+/**
+ * Self-minted stable GA4-style client id. Only used when no _ga cookie
+ * exists, so the worker can forward events to the GA4 Measurement Protocol.
+ */
+function getOrMintClientId(): string {
+    let cid = localStorage.getItem('worker_cid');
+    if (!cid) {
+        cid = Math.floor(Math.random() * 1e10) + '.' + Math.floor(Date.now() / 1000);
+        localStorage.setItem('worker_cid', cid);
+    }
+    return cid;
+}
+
+function getSessionId(): string {
+    try {
+        let sid = sessionStorage.getItem('worker_sid');
+        if (!sid) {
+            sid = Math.floor(Date.now() / 1000) + '';
+            sessionStorage.setItem('worker_sid', sid);
+        }
+        return sid;
+    } catch (err) {
+        return Math.floor(Date.now() / 1000) + '';
+    }
+}
+
+function postToWorker(path: string, payload: any) {
+    const body = JSON.stringify(payload);
+    const url = CONVERSION_WORKER_URL + path;
+    if (navigator.sendBeacon) {
+        navigator.sendBeacon(url, body);
+    } else {
+        fetch(url, { method: 'POST', body, keepalive: true }).catch(() => { });
+    }
+}
+
+/**
+ * Sends every tracking event to the conversion worker:
+ * - to /api/google-ads when an ad click id is stored, so Google Ads can
+ *   import the event as an offline conversion (which event names count, and
+ *   whether they are primary or secondary, is decided in Google Ads by which
+ *   conversion actions exist),
+ * - to /api/google-analytics when no google-analytics cookie exists (gtag
+ *   blocked or never loaded), so the worker forwards the event to the GA4
+ *   Measurement Protocol. Users with a _ga cookie already report via gtag;
+ *   skipping them here prevents double counting.
+ */
+function sendToConversionWorker(type: string, value: number) {
+    try {
+        const adClick = getStoredAdClickId();
+        if (adClick) {
+            postToWorker('/api/google-ads', {
+                type,
+                value,
+                clid: adClick.v,
+                clidKind: adClick.k
+            });
+        }
+        if (!document.cookie.includes('_ga=')) {
+            postToWorker('/api/google-analytics', {
+                type,
+                value,
+                cid: getOrMintClientId(),
+                sid: getSessionId()
+            });
+        }
+    } catch (err) {
+        console.log('# Error on conversion-worker trigger:');
+        console.dir(err);
+    }
+}
+
 export function triggerTrackingEvent(
     type: string,
     value: number,
@@ -40,6 +135,12 @@ export function triggerTrackingEvent(
 
     console.log('triggerTrackingEvent(' + type + ', ' + value + ', redditEventType=' + redditEventType + ' ' + triggeredBefore + '/' + maxPerUser + ')');
 
+    /**
+     * Google Ads conversion worker (runs after the same frequency capping
+     * as the other trackers).
+     */
+    sendToConversionWorker(type, value);
+
     /**
      * Reddit does not have a concept of conversion-value
      * so we only track primary events because otherwise everything would

docs-src/src/theme/Root.tsx

@@ -1,5 +1,5 @@
 import React, { useEffect, useState } from 'react';
-import { onCopy, triggerTrackingEvent } from '../components/trigger-event';
+import { AD_CLICK_STORAGE_ID, onCopy, triggerTrackingEvent } from '../components/trigger-event';
 import { randomNumber } from '../../../plugins/utils';
 import { IconClose } from '../components/icons/close';
 import { Button } from '../components/button';
@@ -317,7 +317,7 @@ function storeAdClickId() {
     for (const k of ['gclid', 'gbraid', 'wbraid']) {
         const v = p.get(k);
         if (v) {
-            localStorage.setItem('click_id', JSON.stringify({ k, v, t: Date.now() }));
+            localStorage.setItem(AD_CLICK_STORAGE_ID, JSON.stringify({ k, v, t: Date.now() }));
             triggerTrackingEvent('click_id_' + k, 0.01, 1);
         }
     }