Hosting your own Fluid XSD schemas

.htaccess

RewriteEngine On

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule .* /index.php [L]

Directory and file structure

[host /htdocs/]$ ls 
index.php  ns

[host /htdocs/]$ ls ns/
News.xsd  TYPO3.CMS.Fluid.xsd  TYPO3.Fluid.xsd

index.php

<?php

$hostName = 'xsd.helmut-hummel.de';
$namespacePrefix = '/ns/';
$namespaceSuffix = '/ViewHelpers';
$requestUri = $_SERVER['REQUEST_URI'];

$packageKey = str_replace('/', '.', preg_replace(
                '#^' . preg_quote($namespacePrefix, '#') . '#', '',
                preg_replace(
                        '#' . preg_quote($namespaceSuffix, '#') . '$#', '',
                        $requestUri
                )
));

$fileName = __DIR__ . '/ns/' . $packageKey . '.xsd';

if (file_exists($fileName)) {
        header('Content-Type: application/xml');
        echo str_replace('targetNamespace="http://typo3.org/ns/Your/Package/ViewHelpers"', 'targetNamespace="http://' . $hostName . '/ns/' . implode('/', explode('.', $packageKey))  . '/ViewHelpers"', file_get_contents($fileName));
        exit;
} else {
        header('HTTP/1.1 404 Not Found');
        echo 'No XSD found for package ' . htmlspecialchars($packageKey);
        exit;
}