Moving middleware to before SiteResolver

[sorenmalling]

With site configs with a base such as

domain.tld/rootpage

A request to

domain.tld/rootpage/

will currently return a "site not found"

Moving the de-slash middleware to before typo3/cms-frontend/site would make the final requested uri be corrected earlier in the middleware chain.

My (un-tested) guess is that will also provide a situation for the redirect handler, where the entry path is always known to be without a trailing slash and all other cases where the URI is used

Ideas, thoughts?

I have a live setup where I will test this idea

[sorenmalling]

Is this relevant and something that we could include in a version for TYPO3 14?

[ChristianOsswald]

The risk about your approach

• Moving the existing middleware earlier in the stack would remove access to resolved routing/site information, which could break Route Enhancers or intentionally configured trailing slashes.

Thought about changing the core

It is likely undesirable because it could/would:

• weaken strict route matching semantics,
• affect language redirects,
• alter unresolved-tail behavior globally,
• and introduce routing ambiguities into core.

So my preferred approach would be another: A Two-Stage Middleware setup

1. small early middleware only for exact /
2. keep the existing route-aware middleware unchanged for everything else

The Two-Stage idea

Stage 1: Early Site-Base Redirect

Add a very small middleware before typo3/cms-frontend/site.

It would only handle exact site-base URLs with a trailing slash, e.g.: /rootpage/ → /rootpage

Implementation idea

• Use SiteFinder->getAllSites()
• Compare the incoming path against /
• If it matches exactly, immediately issue a 301 redirect

This should be safe because site bases are static entry points and don’t involve Route Enhancers or PageTypeSuffix logic.

Stage 2: Keep Existing TrailingSlashRedirector

Leave the current middleware exactly where it is (after routing/page resolving).

That way it still has access to:

• site
• routing
• pageArguments

and can continue respecting Route Enhancers and intentionally configured trailing slashes for normal pages.

Please give feedback

Not fully sure if I’m overlooking edge cases though — curious what others think.