debug webhook 500 errors

To debug webhook 500 errors, I’d approach it in this order:

1. Check the webhook receiver logs

   • Look at the server/app logs for the exact exception, stack trace, and request payload.
   • A 500 means the error is on your side, so the logs usually tell you the real cause.

2. Verify the incoming request

   • Confirm headers, method, and body match what your endpoint expects.
   • Common issues:
     • Invalid JSON
     • Missing required fields
     • Wrong Content-Type
     • Unexpected signature/auth format

3. Reproduce locally

   • Send the same payload with curl, Postman, or a test script.
   • Example:

     curl -X POST https://your-webhook-url \
       -H "Content-Type: application/json" \
       -d '{"test":"value"}'
     

4. Inspect payload handling

   • Make sure your code safely parses the body.
   • Add guards around:
     • JSON decoding
     • nil/undefined fields
     • type mismatches
     • array vs object assumptions

5. Check authentication/signature verification

   • If you validate HMAC/signatures, failures sometimes get handled poorly and turn into 500s.
   • These should usually return 401 or 400, not 500.

6. Look for timeouts or downstream failures

   • If your webhook handler calls databases, APIs, or queues:
     • test those dependencies
     • check for connection errors
     • confirm timeouts aren’t too short

7. Make the handler fail safely

   • Return explicit errors for bad input instead of throwing uncaught exceptions.
   • Example patterns:
     • 400 for malformed payloads
     • 401/403 for auth/signature issues
     • 500 only for unexpected server faults

8. Add better observability

   • Log:
     • request ID / correlation ID
     • event type
     • payload size
     • parsing/auth failures
   • If possible, store failed payloads in a dead-letter queue or error store for replay.

If you want, paste:

• the webhook handler code,
• one failing payload,
• and the stack trace/log output,

and I can help pinpoint the 500.