feat(middleware): Page 404 to 301 | add redirect for old page slugs, caused by title change

[oopen]

📝 Description

This PR introduces a new Laravel middleware, RedirectOldPageSlugs, that automatically redirects requests containing obsolete page slugs to the page’s stable permalink (/link/{id}), which then redirects to the current canonical URL.

🔍 Problem

When a user changes a page’s slug in BookStack:

• The old URL becomes a 404.
• BookStack does not store historical slugs for books or chapters (only pages have revisions via page_revisions).
• External links, bookmarks, or search engine results pointing to the old URL break permanently.

This creates a poor user experience and harms SEO.

✅ Solution

The new middleware:

• Runs early in the web middleware stack (after TrustProxies, before PageViewCounter).
• Extracts the last path segment from the request (e.g., /book/foo/bar → bar).
• Checks if this segment exists as a non-current slug in page_revisions.
• If found, issues a 301 redirect to /link/{page_id} — BookStack’s built-in, stable permalink route.
• Skips API, asset, debug, and system routes to avoid interference.

This approach is:

• 100% reliable for pages (uses real revision data).
• Independent of book/chapter slug history (which BookStack doesn’t store).
• Zero-config and fully automatic.
• Safe: only redirects when an exact match is found in revisions.

🧪 Testing

1. Create a page → note its slug.
2. Edit the page and change its slug.
3. Visit any URL ending with the old slug (e.g., /any/book/or/chapter/path/old-slug).
4. ✅ Observe a 301 redirect to /link/{id}, then to the current page.

Note: The middleware matches any path ending with the old slug, because BookStack’s routing is dynamic and doesn’t enforce strict path structures. This ensures maximum compatibility.

📁 Files Changed

• app/Http/Middleware/RedirectOldPageSlugs.php → new middleware
• app/Http/Kernel.php → register middleware in web group

⚙️ Middleware Placement

Inserted after TrustProxies and before PageViewCounter to:

• Avoid counting redirected requests as page views.
• Ensure trusted proxy headers are processed first.

💡 Why /link/{id} and not the canonical URL?

• /link/{id} is BookStack’s official, stable permalink mechanism.
• It already handles final redirection to the current URL (including updated book/chapter slugs).
• This avoids duplicating routing logic and ensures consistency.

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✅ Benefits

• Restores broken links automatically.
• Improves SEO by preserving link equity via 301s.
• Requires no user intervention or configuration.
• Minimal performance impact (indexed DB lookup on page_revisions.slug).

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🙏 Final Note

This feature aligns with BookStack’s philosophy of usability and data integrity, and leverages existing systems (page_revisions, /link/{id}) without introducing redundancy.

Thank you for considering this contribution!

[ssddanbrown]

Thanks for offering this @oopen, but this isn't the approach I'd like to take, and as mentioned in #5827 I'm awaiting on other changes before adding this kind of functionality.

Also, please avoid writing PRs (text/code) with heavy AI use for this project.
It adds a lot of extra incorrect information, and code that does not understand the full context which can result in issues or odd behaviour/decisions.

[oopen]

Ok, I read your plan to update the DB first, it a good thing.

But please consider this redirection feature as a "temporary mitigation hack",
and can be removed after when you complete the plan you described #5800

It make no change to the app/DB, just fix a big part of 404 links immediately.