For a while I have been creating and sending links to History Keeper to http://www.unfocus.com/projects/HistoryKeeper/. When I moved that page into WordPress the URL became lower case, and case sensitive. This can be a problem for those used to Windows and IIS non-case sensitive URLs. To get around the problem, I added a hack to my 404.php error handler (more on that later) that would detect capitals in the permalink URL, convert it to lowercase, and then forward the user to the new page with a php Location header (http redirect). That seemed like a clunky solution, so I made a WordPress plugin that does pretty much the exact same thing, only it’s in a plugin! So that makes it less clunky. Well whatever.
Here’s the code:
[cc lang=’php’ ]
< ?php
/*
Plugin Name: unFocus.Insensitivity
Plugin URI: http://www.unfocus.com/projects/
Description: A plugin to make permalinks case insensitive.
Version: 1.0a
Author: Kevin Newman
Author URI: http://www.unfocus.com/projects/
*/
function unFocus_insensitivity() {
if (preg_match('/[A-Z]/', $_SERVER['REQUEST_URI'])) {
$_SERVER['REQUEST_URI'] = strtolower($_SERVER['REQUEST_URI']);
$_SERVER['PATH_INFO'] = strtolower($_SERVER['PATH_INFO']);
}
}
add_action('init', 'unFocus_insensitivity');
?>
[/cc]
Pretty simple really. Honestly, it doesn’t really even need to use a WordPress hook, just the two lines that convert the $_SERVER variables would do it (assuming those aren’t locked down in the php.ini). But I wanted to learn the plugin API anyway. There is an archive download at the end of this post, just unzip the enclosed file, and put it in your plugin directory, upload it and turn it on. No other configuration necessary.
If there is any interest, I was thinking about adding a config option that would allow you to either forward to the all lowercase URL, or to do what it does now, which is to behave pretty much the way IIS does for any other static files it hosts.
Also, if there’s interest, I may try to figure a way to work this WordPress IIS Permalink 404 handler into the plugin, if it’s possible (IIS users would set their custom 404 handler redirect URLs to redirect to /wordpresslocation/index.php instead of /wordpresslocation/404.php, which is how you do it now):
[cc lang=’php’ ]
< ?php
$_SERVER['REQUEST_URI'] = substr(
$_SERVER['QUERY_STRING'],
strpos(
$_SERVER['QUERY_STRING'],
':80'
) +3
);
$_SERVER['PATH_INFO'] = $_SERVER['REQUEST_URI'];
include('index.php');
?>
[/cc]
The archive – unFocus.Insensitivity
Update: Fixed the download link.
Thanks for the plugin. It works great and did exactly what I wanted it to!
Glad I could help! 🙂
Great post. We owe you a beer!
Sweet! I’ll take a nice Bard’s Tale Golden Dragon Lager! 🙂
Sir, you are a gentleman and a scholar! Many thanks for this.
This post is so old, but seems to still be useful. I may have to put this up on wordpess.org.
Doesn’t seem to work anymore…
With all the work that has gone into core, and into IIS for that matter, this really shouldn’t be needed. Also, I no longer maintain this, since I’m on Apache hosting now.
Wish to express our thanks. Thanks!!!!!
bummer… doesesnt work?
needed a plugin that does the opposite.
would it if i change to lower to upper ?
It should be possible to do that with a plugin called redirection and a simple regex to convert everything to uppser case. I’d say look into that: http://urbangiraffe.com/plugins/redirection/
Checked it out tonight and sad to say, it did not work. Any further updates coming?
I haven’t worked on this in quite a long while. My site now works without it, and urls are not case sensitive. Since it’s already like that here, I’m not sure how I’d approach an update. One note; I am using a plugin called Redirection. Perhaps that disables case sensitivity?
This plugin is exactly what I was looking for. It saved me from having to change the domain in books that had already been submitted for publication.
I’m glad it worked for you. 🙂
Nice! Thanks hommie!
Great work Kevin.. Your code might be old, but it still do work!
Thanks a lot.
Megha
Just wanted to say a BIG THANK YOU for this! Exactly what I needed.
Excellent! It took me 3 days to find a solution to this issue, THANKS MR NEWMAN!
September 2014 and this plugin is still working a treat. Thank you sir!
THANK YOU! This worked like a charm – it’s virtually never this easy to troubleshoot a WordPress problem.