Rob Allen's DevNotes

I've written before about URL rewriting with IIS7's URL Rewrite module.

IIS6, which ships with Windows Server 2003 does not have this module though and guess which version my client's IT dept run? As usual, they wouldn't install ISAPI_Rewrite or one of the other solutions for me. In the past, I've simply written a new router that creates URLs with normal GET variables, but this is ugly and I wanted better.

One thing IIS6 does let you do is configure a URL to be called upon a 404 error, which then allows you to have "pretty" URLs and be able to route them.

Firstly, I set up the URL handler in the IIS Manager:

This will result in all unrecognised URLs being redirected to index.php. The standard Zend_Controller_Request_Http object will automatically extract the URL and routing works as expected.

However, there are three problems:

1. The $_POST array is always empty
2. $_SERVER['REQUEST_METHOD'] is always GET, even for a post request
3. The first key in $_GET has been mangled by IIS

As Zend Framework wraps up the request into a Request object, this is fairly simple to work around by creating our own Request object.

class App_Controller_Request_Iis404 extends Zend_Controller_Request_Http
{
    /**
     * Constructor
     *
     * If a $uri is passed, the object will attempt to populate itself using
     * that information.
     *
     * @param string|Zend_Uri $uri
     * @return void
     * @throws Zend_Controller_Request_Exception when invalid URI passed
     */
    public function __construct($uri = null)
    {
        // As Zend_Controller_Request_Http accesses the superglobals directly, we
        // will have to write into $_GET and $_POST directly

        // The post variables can be accessed from php://input
        $input = file_get_contents('php://input');
        if (strlen($input)) {
            $input = urldecode($input);
            parse_str($input, $_POST);
        }
        
        // fix $_GET
        foreach ($_GET as $key=>$value) {
            if (substr($key, 0, 4) == '404;') {
                // special key created by IIS - the actual key name is after the ?
                $bits = explode('?', $key);
                if (count($bits) > 1) {
                    $_GET[$bits[1]] = $value;
                }
            }
        }
        
        return parent::__construct($uri);
    }
    
    /**
     * Return the method by which the request was made
     *
     * @return string
     */
    public function getMethod()
    {
        if (!empty($_POST)) {
            return 'POST';
        }
        
        return parent::getMethod();
    }
}

We start by reading the php://input stream which on a POST request will hold the POST variables. We can then transfer them to the $_POST array. Similarly, the key in the $_GET array that has been mangled, is easy to detect as it starts with '404;'. We can then find the ? and the part after it is the real key, so we create a new $_GET element for that item. Finally, we override getMethod() and return 'POST' if there are any elements in $_POST.

To use a custom Request object, you need to create an _init method in your Bootstrap:

class Bootstrap extends Zend_Application_Bootstrap_Bootstrap
{
    function _initIis404RequestObject()
    {
        $options = $this->getOptions();
        $this->bootstrap('frontController');
        $frontController = $this->getResource('frontController');
        $frontController->setRequest($options['frontController']['requestClass']);  
    }

Zend Framework's standard URLs now work nicely with IIS6 on Window Server 2003.

This entry was posted on Monday, 16th November 2009 at 07:55 and is filed under Zend Framework.