Prefix n' Shorten not working because of uri slash

[flashlab]

If I enter https://sho.rt/subpath/https://longurl.com/something.html, I always been redirect to YOURLS_SITE(https://sho.rt/subpath/). What I want is to use prefix to quickly shorten urls.
So I did some debugging. In yourls_get_request, the $_SERVER[ 'REQUEST_URI' ] returned /subpath/https:/longurl.com/something.html which /subpath/https://longurl.com/something.html is expected.
The problem is https:// turn into https:/ with one slash missing.
I thought the problem maybe come from apache rewrite rules, here is my .htaccess file in YOURLS root folder:

# BEGIN YOURLS
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /u/
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^.*$ /u/yourls-loader.php [L]
</IfModule>
# END YOURLS

Can anyone help me to solve it?

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$request = preg_replace('/^(https?):\/(?!\/)/', "$1://", $request, 1);

This is the ugly solution.

[dgw]

I have YOURLS installed at the domain root, but I added a temporary copy of the files at /subdir/ to test this. The only changes from my root .htaccess were adding subdir/ to the RewriteBase and RewriteRule lines:

# BEGIN YOURLS
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /subdir/  # in /, this is `RewriteBase /`
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^.*$ /subdir/yourls-loader.php [L]  # in /, this is `RewriteRule ^.*$ /yourls-loader.php [L]
</IfModule>
# END YOURLS

And I changed YOURLS_SITE to include subdir/ as well in user/config.php.

On both my root install and the temporary subdir copy, prefix-n-shorten worked as expected. Both https://domain.tld/https://some-other.site and https://domain.tld/subdir/https://some-other.site created a new shortlink and redirected as expected.

A quick search tells me that MergeSlashes is probably enabled in your Apache configuration. This feature (I guess they consider it a feature) was added in Apache 2.4.39, and it's on by default.

My site (on shared hosting) is a bit behind that version; I'll have to keep MergeSlashes in mind for my own installation whenever the host upgrades things. It doesn't look like I can turn it off at the .htaccess level, so I just might have to ask support to change the vhost configuration for me if the eventual Apache update breaks this feature… Thanks for putting it on my radar. 🙂

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An alternative cause could be ProxyPass canonicalizing proxied URLs, if you are using mod_proxy in front of YOURLS. The nocanon keyword will suppress this, but the recently-added MergeSlashes directive above is the more likely cause.

[flashlab]

@dgw I checked my apache info, here is the output:

➜  ~ /usr/local/apache/bin/apachectl -V
Server version: Apache/2.4.55 (Unix)
Server built:   Jun 29 2023 05:10:23
Server's Module Magic Number: 20120211:126
Server loaded:  APR 1.5.2, APR-UTIL 1.5.4, PCRE 8.37 2015-04-28
Compiled using: APR 1.5.2, APR-UTIL 1.5.4, PCRE 8.37 2015-04-28
Architecture:   64-bit
Server MPM:     worker
  threaded:     yes (fixed thread count)
    forked:     yes (variable process count)
Server compiled with....
 -D BIG_SECURITY_HOLE
 -D APR_HAS_SENDFILE
 -D APR_HAS_MMAP
 -D APR_HAVE_IPV6 (IPv4-mapped addresses enabled)
 -D APR_USE_SYSVSEM_SERIALIZE
 -D APR_USE_PTHREAD_SERIALIZE
 -D SINGLE_LISTEN_UNSERIALIZED_ACCEPT
 -D APR_HAS_OTHER_CHILD
 -D AP_HAVE_RELIABLE_PIPED_LOGS
 -D DYNAMIC_MODULE_LIMIT=256
 -D HTTPD_ROOT="/root/daily_build/510_10/5.1.0/NasMgmt/HTTP/apache_install_tmp"
 -D SUEXEC_BIN="/root/daily_build/510_10/5.1.0/NasMgmt/HTTP/apache_install_tmp/bin/suexec"
 -D DEFAULT_PIDLOG="logs/httpd.pid"
 -D DEFAULT_SCOREBOARD="logs/apache_runtime_status"
 -D DEFAULT_ERRORLOG="logs/error_log"
 -D AP_TYPES_CONFIG_FILE="/etc/config/apache/mime.types"
 -D SERVER_CONFIG_FILE="/etc/config/apache/apache.conf"

It seems MergeSlashes was not been shutdown.If so, I'll have to use the temporary solution, Thanks for your help.

[dgw]

FYI, if you were looking for information about it in the compilation options, MergeSlashes is not set at compile time. You are running a version newer than when the feature was added, so if you do not want it enabled, you'll have to add the option MergeSlashes off into one of the supported configuration files (server config or vhost config).

[flashlab]

@dgw I've figure out it was ProxyPass that do the trick in my situation.
After append nocanon within ProxyPass, everything works fine.
Just want you to know about it.

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The sad story is: nocanon affect mediawiki api requests, so I have to use the ugly solution for now T.T