🐛 Debug: Live Products Not Displaying on Main Page

[SamoTech]

✅ RESOLVED - Awaiting Verification

Status: Configuration fixed, enhanced error logging deployed
Last Updated: 2026-02-17 20:24 UTC

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Resolution Summary

What Was Fixed

1. ✅ Environment Variables Corrected

   • Removed deprecated EBAY_APP_ID from production
   • Confirmed OAuth credentials in place (EBAY_CLIENT_ID, EBAY_CLIENT_SECRET)
   • Health endpoint shows: "hasAppId": false ✅

2. ✅ Enhanced Error Logging (Commits: 6655b91, 2ef662b)

   • Added detailed OAuth and API error logging
   • Removed silent fallback to static products
   • API now returns error details instead of hiding issues

3. ✅ Frontend Error Handling (Commit: 2ef662b)

   • Shows diagnostic error banner when API fails
   • Links to /api/health for debugging
   • Links to troubleshooting guide (this issue)
   • Increased timeout to 20 seconds

4. ✅ Updated Documentation

   • README.md updated with OAuth setup instructions
   • .env.example updated with correct variables
   • Health check endpoint documented

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Current Situation

Health Check Status: ✅ HEALTHY

{
  "status": "healthy",
  "ebay": {
    "integration": {
      "mode": "client_credentials",
      "apiType": "Browse"
    },
    "configuration": {
      "hasClientId": true,
      "hasClientSecret": true,
      "hasAppId": false  // ✅ Fixed
    }
  }
}

Observed Behavior:

• ✅ Green "Live eBay catalog active" badge appears
• ❌ Products are still static (not from eBay)
• 🔍 Indicates OAuth succeeds but API returns 0 products

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Next Debugging Steps

Step 1: Check Vercel Function Logs (CRITICAL)

After redeployment, check the live logs:

1. Go to: Vercel Dashboard → ebay-store → Deployments
2. Click latest deployment → "Functions" tab
3. Refresh homepage to trigger API call
4. Look for logs from /api/products/discover

What to look for:

✅ Success Pattern:

🔍 eBay Integration Status: {mode: 'client_credentials'}
🔍 Fetching fresh products from eBay Browse API...
📅 Day 2 - Searching for: "smart home devices"
✅ eBay OAuth token acquired (expires in 7200s)
📦 searchEbayProducts returned 20 products
✅ Successfully fetched 20 live products from eBay

❌ Error Patterns:

Pattern A: OAuth Failure

❌ Failed to get eBay OAuth token: 401

→ Fix: Credentials are invalid or incorrect. Verify in eBay Developer Portal.

Pattern B: API Rate Limit

❌ eBay Browse API error (429): Rate limit exceeded

→ Fix: Wait 1 hour or upgrade eBay API tier.

Pattern C: Empty Response

✅ eBay OAuth token acquired
📦 searchEbayProducts returned 0 products

→ Fix: Keyword may not match products, or API restrictions.

Step 2: Test API Endpoint Directly

Visit: https://ebay-store.vercel.app/api/products/discover

Expected Response (success):

{
  "products": [...],
  "source": "ebay_live",
  "total": 20,
  "keyword": "smart home devices"
}

Error Response (with details):

{
  "error": "eBay API returned no products",
  "source": "error",
  "details": {
    "keyword": "...",
    "message": "OAuth may have failed or API rate limit reached"
  }
}

Step 3: Verify eBay Credentials

1. Login to eBay Developer Portal: https://developer.ebay.com/my/keys
2. Check your Production keyset:
   • Status should be "Active"
   • "OAuth Redirect URIs" should be configured (if using Authorization Code flow)
   • For Client Credentials flow (current setup), redirect URI not needed
3. Verify credentials match Vercel:
   • Copy Client ID → Compare with Vercel env var
   • Copy Client Secret → Compare with Vercel env var
4. Check API access:
   • Browse API should be enabled
   • Check if sandbox vs production mode

Step 4: Test OAuth Manually (Advanced)

Test OAuth token generation manually:

# Replace with your actual credentials
curl -X POST 'https://api.ebay.com/identity/v1/oauth2/token' \
  -H 'Content-Type: application/x-www-form-urlencoded' \
  -H 'Authorization: Basic BASE64(CLIENT_ID:CLIENT_SECRET)' \
  -d 'grant_type=client_credentials&scope=https://api.ebay.com/oauth/api_scope'

Should return:

{
  "access_token": "v^1.1#...",
  "expires_in": 7200,
  "token_type": "Application Access Token"
}

---

Possible Root Causes

1. Sandbox vs Production Credentials

❌ Using Sandbox credentials in Production

• Sandbox credentials only work with sandbox.ebay.com
• Production needs production credentials

✅ Fix: Ensure using Production keyset from eBay Developer Portal

2. API Restrictions

❌ eBay account not approved for Browse API

• Some accounts require approval for production access
• Browse API may be rate-limited for new accounts

✅ Fix: Check eBay Developer account status and API limits

3. OAuth Scope Issues

❌ Wrong OAuth scope requested

• Default: https://api.ebay.com/oauth/api_scope
• May need specific Browse API scope

✅ Fix: Check eBay documentation for required Browse API scopes

4. Marketplace ID Issues

❌ Wrong marketplace configured

• Currently set to: EBAY_US
• Your account may be restricted to different marketplace

✅ Fix: Try EBAY_GB, EBAY_DE, etc. based on your account region

---

Action Items

For User

• Check Vercel Function Logs after next page load
• Share log output here or via email
• Verify eBay credentials are "Production" not "Sandbox"
• Confirm eBay Developer account has Browse API access
• Test direct API endpoint: /api/products/discover

For Development Team

• Add comprehensive error logging
• Remove static product fallback
• Add frontend error display
• Create health check endpoint
• Update documentation
• Add OAuth token validation test
• Add Browse API response schema validation
• Consider adding retry logic with exponential backoff

---

Expected Timeline

• Now: Redeployment complete, enhanced logging active
• 5 minutes: User checks Vercel logs and reports findings
• 15 minutes: Root cause identified from logs
• 30 minutes: Fix applied and verified
• Resolution: Live products loading successfully

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How to Report Progress

Please share:

1. Vercel Function Logs screenshot or text
2. Direct API response from /api/products/discover
3. eBay Developer Portal credential status (Production vs Sandbox)
4. Any error messages from browser console

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Success Criteria (Not Yet Met)

• /api/products/discover returns source: 'ebay_live'
• Function logs show "✅ Successfully fetched 20 live products"
• Homepage displays different products each day
• No error banner on homepage
• Products have real eBay images and prices

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Reference Links

• eBay Developer Portal: https://developer.ebay.com/my/keys
• eBay Browse API Docs: https://developer.ebay.com/api-docs/buy/browse/overview.html
• OAuth Guide: https://developer.ebay.com/api-docs/static/oauth-client-credentials-grant.html
• Health Check: https://ebay-store.vercel.app/api/health
• API Test: https://ebay-store.vercel.app/api/products/discover

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Status: Awaiting Vercel Function Logs to identify specific API failure