[BUG] Fix Cloudflare Turnstile widget not loading on Vercel production

[gensecai-dev]

Problem

The Cloudflare Turnstile bot protection widget is not loading on Vercel production deployment. The widget shows "Security verification bypassed - widget failed to load" message instead of rendering properly.

Current Status: Turnstile validation has been temporarily disabled (commit 7dfe511) to unblock user flow, but all implementation code remains intact for future fixes.

Environment

• Platform: Vercel (Production)
• Mode: Non-interactive Turnstile
• Environment Variables: ✅ Properly configured in Vercel dashboard
  • TURNSTILE_SECRET_KEY (All Environments)
  • NEXT_PUBLIC_TURNSTILE_SITE_KEY (All Environments)

What's Already Implemented

Frontend (src/components/PrivacyAnalyzer.tsx)

• ✅ Native Cloudflare Turnstile JavaScript API integration
• ✅ Explicit widget rendering with window.turnstile.render()
• ✅ Proper callbacks (success, error, expired, timeout)
• ✅ Non-interactive mode configuration (appearance: 'interaction-only')
• ✅ Runtime environment variable loading via useEffect
• ✅ Widget lifecycle management (render, reset, cleanup)

Backend (src/app/api/analyze/route.ts)

• ✅ Server-side token verification against Cloudflare API
• ✅ Hostname validation
• ✅ Proper error handling with specific error messages
• ✅ Fraud detection with remoteip parameter

Script Loading (src/app/layout.tsx)

• ✅ Turnstile script loaded: https://challenges.cloudflare.com/turnstile/v0/api.js

Issue Details

Despite correct implementation according to official Cloudflare documentation, the widget fails to load on Vercel production. Local environment was not tested.

Attempted Fixes

1. ✅ Replaced third-party React wrapper with native API
2. ✅ Fixed environment variable loading (build-time → runtime)
3. ✅ Fixed infinite re-render issues in useEffect
4. ✅ Configured non-interactive mode
5. ✅ Enhanced server-side validation
6. ✅ Added comprehensive error handling and logging

Disabled Code

The validation check is currently commented out (lines 186-191 in PrivacyAnalyzer.tsx):

// TURNSTILE DISABLED - Keep code for future use
// if (TURNSTILE_SITE_KEY && !turnstileToken && !turnstileBypass) {
//   setError('Please complete the security verification');
//   return;
// }

Potential Root Causes to Investigate

1. Vercel-specific configuration issues

   • Content Security Policy blocking Cloudflare script
   • Next.js build/runtime configuration conflicts
   • Environment variable propagation timing

2. Network/CDN issues

   • Turnstile script not loading from Cloudflare CDN
   • CORS or network policy blocking requests

3. Widget initialization timing

   • Script loading race conditions
   • React hydration conflicts

Expected Behavior

The Turnstile widget should:

1. Load and render automatically in non-interactive mode
2. Show a loading bar while challenge runs
3. Generate a token upon successful completion
4. Allow form submission with valid token

Acceptance Criteria

• Turnstile widget renders correctly on Vercel production
• Widget completes verification in non-interactive mode
• Token is generated and validated server-side
• Form submission works with valid token
• Error states handled gracefully
• Uncomment validation check in PrivacyAnalyzer.tsx (lines 186-191)

Documentation References

• Cloudflare Turnstile Client-Side Rendering
• Cloudflare Turnstile Server-Side Validation

Files to Review

• src/components/PrivacyAnalyzer.tsx - Frontend widget integration
• src/app/api/analyze/route.ts - Backend verification (lines 310-361)
• src/app/layout.tsx - Script loading (line 108)
• .env.example - Environment variable documentation

---