freebuff: Identify who referred each new user

Author: jahooma

common/src/constants/analytics-events.ts

@@ -147,6 +147,9 @@ export enum AnalyticsEvent {
   CHATGPT_OAUTH_RATE_LIMITED = 'sdk.chatgpt_oauth_rate_limited',
   CHATGPT_OAUTH_AUTH_ERROR = 'sdk.chatgpt_oauth_auth_error',
 
+  // Freebuff - Referral Attribution
+  FREEBUFF_REFERRER_ATTRIBUTED = 'freebuff.referrer_attributed',
+
   // Freebuff - Get Started Page
   FREEBUFF_GET_STARTED_VIEWED = 'freebuff.get_started_viewed',
   FREEBUFF_GET_STARTED_HELP_EXPANDED = 'freebuff.get_started_help_expanded',

freebuff/web/src/app/get-started/get-started-client.tsx

@@ -103,6 +103,9 @@ export default function GetStartedClient({
     posthog.capture(AnalyticsEvent.FREEBUFF_GET_STARTED_VIEWED, {
       referrer: referrerName,
     })
+    if (referrerName) {
+      localStorage.setItem('freebuff_referrer', referrerName)
+    }
   }, [referrerName])
 
   return (

freebuff/web/src/app/onboard/page.tsx

@@ -13,6 +13,7 @@ import {
 import { isAuthCodeExpired, parseAuthCode, validateAuthCode } from './_helpers'
 import { authOptions } from '../api/auth/[...nextauth]/auth-options'
 
+import { ReferrerTracker } from '@/components/referrer-tracker'
 import {
   Card,
   CardHeader,
@@ -40,6 +41,7 @@ function StatusCard({
 }) {
   return (
     <main className="container mx-auto flex flex-col items-center py-20">
+      <ReferrerTracker />
       <div className="w-full sm:w-1/2 md:w-2/3">
         <Card>
           <CardHeader>

freebuff/web/src/components/referrer-tracker.tsx

@@ -0,0 +1,20 @@
+'use client'
+
+import { AnalyticsEvent } from '@codebuff/common/constants/analytics-events'
+import posthog from 'posthog-js'
+import { useEffect } from 'react'
+
+export function ReferrerTracker() {
+  useEffect(() => {
+    const referrer = localStorage.getItem('freebuff_referrer')
+    if (referrer) {
+      posthog.capture(AnalyticsEvent.FREEBUFF_REFERRER_ATTRIBUTED, {
+        referrer,
+        $set_once: { freebuff_referrer: referrer },
+      })
+      localStorage.removeItem('freebuff_referrer')
+    }
+  }, [])
+
+  return null
+}