[Closes #34] Add Posthog cookieless analytics (#53)

* [Closes #34] Add Posthog cookieless analytics

* Revert server modification for posthog- unnecessary

Author: francisli

client/package.json

@@ -27,6 +27,7 @@
     "i18next-http-backend": "^3.0.2",
     "inflection": "^3.0.2",
     "luxon": "^3.7.2",
+    "posthog-js": "^1.270.1",
     "prop-types": "^15.8.1",
     "react": "^19.1.1",
     "react-dom": "^19.1.1",

client/src/StaticContext.js

@@ -9,6 +9,8 @@ export const defaultValue = {
   env: {
     VITE_SITE_TITLE: import.meta.env.VITE_SITE_TITLE,
     VITE_FEATURE_REGISTRATION: import.meta.env.VITE_FEATURE_REGISTRATION,
+    VITE_PUBLIC_POSTHOG_KEY: import.meta.env.VITE_PUBLIC_POSTHOG_KEY,
+    VITE_PUBLIC_POSTHOG_HOST: import.meta.env.VITE_PUBLIC_POSTHOG_HOST,
   },
 };
 

client/src/entry-client.jsx

@@ -2,20 +2,31 @@ import React from 'react';
 import { createRoot, hydrateRoot } from 'react-dom/client';
 import { BrowserRouter } from 'react-router';
 import { createHead, UnheadProvider } from '@unhead/react/client';
+import { PostHogProvider } from 'posthog-js/react';
 
 import App from './App';
 import { defaultValue } from './StaticContext';
 import StaticContextProvider from './StaticContextProvider';
 
+const staticContext = { ...defaultValue, ...window.STATIC_CONTEXT };
+
+const posthogOptions = {
+  cookieless_mode: 'always',
+  api_host: staticContext.env.VITE_PUBLIC_POSTHOG_HOST,
+  defaults: '2025-05-24',
+};
+
 const head = createHead();
 
 const container = document.getElementById('root');
 const app = (
-  <StaticContextProvider value={{ ...defaultValue, ...window.STATIC_CONTEXT }}>
+  <StaticContextProvider value={staticContext}>
     <UnheadProvider head={head}>
-      <BrowserRouter>
-        <App />
-      </BrowserRouter>
+      <PostHogProvider apiKey={staticContext.env.VITE_PUBLIC_POSTHOG_KEY} options={posthogOptions}>
+        <BrowserRouter>
+          <App />
+        </BrowserRouter>
+      </PostHogProvider>
     </UnheadProvider>
   </StaticContextProvider>
 );