wrong 404 page shown for URLs that have no suffix

[fritzmg]

Tested with Contao 4.4.7.

Reproduction:

1. Set the primary and secondary language of your browser to English.
2. Leave the contao.url_suffix at its default value (.html).
3. Set prepend_locale: true, clear the cache.
4. Create a website root for language en.
5. Create a 404 page with English text within that website root.
6. Create a website root for language de.
7. Create a 404 page with German text within that website root.
8. Test the following URLs:

• http://example.org/de/foo.html
• http://example.org/de/foo

The first URL will show the German 404 page as expected.

The second URL will show the English 404 page, even though the URL clearly has the /de language fragment in it.

As indicated with the first reproduction step, the language shown for such a URL depends on the Accept-Language of the request header actually. So if your browser is set to German, you can test with the following URLs instead:

• http://example.org/en/foo.html
• http://example.org/en/foo

The first URL will show the English 404 page, the second one will show the German 404 page.

[leofeyer]

@contao/developers Do you think we should handle this case? URLs without the URL suffix are not valid Contao URLs and therefore Contao should not try to extract anything from them IMO.

[ausi]

If it’s an easy fix, I think we should do it.

[Toflar]

URLs without the URL suffix are not valid Contao URLs and therefore Contao should not try to extract anything from them IMO.

I agree, it's not a Contao URL so why does it redirect to the English 404 page then? :D

[fritzmg]

It does not redirect, it simply generates the 404 page of the primary Accept-Language (or fallback).

[bytehead]

URLs without the URL suffix are not valid Contao URLs

What if I configured an empty URL suffix?

[fritzmg]

What if I configured an empty URL suffix?

Then such URLs would show the regular 404 page and URLs with an URL suffix possibly will not.

[bytehead]

Contao should only handle this kind of cases, when a route with a contao_ prefix matches.

[fritzmg]

Contao should only handle this kind of cases, when a route with a contao_ prefix matches.

Which is true for any URL ;) routing.yml#L25-L33

# The catch all route must be the last one!
contao_catch_all:
    path: /{_url_fragment}
    defaults:
        _scope: frontend
        _token_check: true
        _controller: "ContaoCoreBundle:Frontend:index"
    requirements:
        _url_fragment: .*

[bytehead]

contao_catch_all should be the very last rule of the routing config.

[fritzmg]

Yes of course, but that's not the point. Any URL (that is not physically present or catched otherwise) is a valid Contao URL currently.

[bytehead]

Any URL is a valid Contao URL currently.

Thats a problem, if somebody has a Symfony application and adds the contao\core-bundle later.
Contao should only care about Contao URLs and not about others.

[fritzmg]

Yes, but Contao URLs are currently only processed via the contao_root and contao_catch_all route.

If you use the core-bundle in your Symfony app, you yourself need to make sure that its routes are the last ones loaded.

[Toflar]

This is indeed an issue, we have to do something about it. It was completely confusing for me and I debugged quite a bit and didn't even remember that issue here :) So either the issue is that it does not find the correct 404 page to render or the issue is that it tries to render one even though it should not be considered a Contao request.
We can handle this case properly once we switch to proper router handling but until then, we have to make a decision here.

[leofeyer]

As discussed in Mumble on February 15th, a first step to solving the problem would be to move this block

core-bundle/src/Resources/contao/classes/Frontend.php

Lines 99 to 121 in 483e7fe

	// Extract the language
	if (\Config::get('addLanguageToUrl'))
	{
	$arrMatches = array();
	// Use the matches instead of substr() (thanks to Mario Müller)
	if (preg_match('@^([a-z]{2}(-[A-Z]{2})?)/(.*)$@', $strRequest, $arrMatches))
	{
	\Input::setGet('language', $arrMatches[1]);
	// Trigger the root page if only the language was given
	if ($arrMatches[3] == '')
	{
	return null;
	}
	$strRequest = $arrMatches[3];
	}
	else
	{
	return false; // Language not provided
	}
	}

before this block

core-bundle/src/Resources/contao/classes/Frontend.php

Lines 82 to 97 in 483e7fe

	// Remove the URL suffix if not just a language root (e.g. en/) is requested
	if ($strRequest != '' && (!\Config::get('addLanguageToUrl') || !preg_match('@^[a-z]{2}(-[A-Z]{2})?/$@', $strRequest)))
	{
	$intSuffixLength = \strlen(\Config::get('urlSuffix'));
	// Return false if the URL suffix does not match (see #2864)
	if ($intSuffixLength > 0)
	{
	if (substr($strRequest, -$intSuffixLength) != \Config::get('urlSuffix'))
	{
	return false;
	}
	$strRequest = substr($strRequest, 0, -$intSuffixLength);
	}
	}

[leofeyer]

Fixed in fae22c6.

[fritzmg]

This still happens in Contao 4.4.18.

[fritzmg]

Still happening in Contao 4.4.26 & 4.6.6

[leofeyer]

Apparently, the change from fae22c6 is no longer there. It is actually not in the history, either. 🤔

Re-added in contao/contao@65b5d55.