A contact-form rollback plan should recover the complete submission path: the page, client validation, server handler, anti-abuse controls, notification or ticket destination, confirmation message, and retained submission data. Restoring only the visible HTML can leave a form that appears normal but drops messages or weakens security.
Map the submission path
Record the form URL, deployed frontend version, handler or function version, fields, required and optional states, destination mailbox or system, spam controls, rate limits, secrets owner, retention rule, and monitoring. Do not put live tokens or passwords in the runbook. Identify their approved secret references instead.
Create synthetic test cases for a valid submission, missing required fields, invalid formats, maximum lengths, special characters, repeated submission, attachment limits when applicable, and bot-like traffic. Use fictional personal information and a controlled test destination.
Preserve validation and security expectations
MDN’s client-side form validation guidance explains built-in and scripted browser validation, while also warning that client-side checks are not a substitute for server-side validation. Record the expected browser behavior, but make server acceptance and rejection part of the rollback test.
The OWASP Input Validation Cheat Sheet recommends validating input as early as practical and applying both syntactic and semantic checks. Preserve the accepted field rules, length limits, character handling, allowlists where appropriate, and safe error behavior. A rollback must not reintroduce a known validation weakness.
Build an isolated test route
Deploy the current and prior versions to a staging host or private preview that uses a test mailbox, queue, or ticket project. Keep production credentials and customer messages out of the exercise. Record release identifiers and configuration differences for both frontend and backend components.
Run the fixture against the current version to establish a baseline. Confirm HTTP status, visible success or error message, server receipt, downstream delivery, timestamp, and unique submission identifier. Check that refresh or retry does not unexpectedly create duplicates.
Execute the rollback
Restore the prior frontend and handler through the approved deployment system. Confirm that environment variables, domain allowlists, CAPTCHA or anti-abuse configuration, and notification routing match the restored version. Run the same fixture again. Verify that valid messages arrive once and invalid messages are rejected consistently on the server.
Check accessibility: labels, instructions, focus movement, error association, keyboard use, and confirmation messaging. Test a failure of the downstream mailbox or ticket system and confirm that the handler exposes an operational alert without leaking message contents or stack traces to the visitor.
Decide whether the rollback passed
Compare submission counts, delivery latency, validation results, duplicate behavior, logs, and security controls. Review the monitoring or audit trail for both deployments. A rollback fails if it restores delivery but disables required anti-abuse, privacy, accessibility, or server-validation controls.
Record the operator, timestamps, versions, fixture, results, discrepancies, and total recovery time. Remove synthetic submissions under the normal retention process. Update the plan for every manual step or missing dependency, and repeat after changes to the form provider, backend, domain, secret handling, spam control, or destination system.
Sources
- Client-side form validation — MDN Web Docs
- Input Validation Cheat Sheet — OWASP Foundation