Example view helper for media urls

gistfile1.php

<?php
class Zend_View_Helper_MediaURL extends Zend_View_Helper_Abstract
{
    /**
     * Retrieves the full URL for a static media element, based on the path
     *
     * @param string $path The path of the file, including the '/' prefix
     *
     * @return string
     */
    public function mediaURL($path)
    {
        $name = isset($_SERVER['SERVER_NAME']) ? $_SERVER['SERVER_NAME'] : '';

        // In produciton, use the minified JS version
        if (substr($path, -3) == '.js'
            && substr($path, -6) !== 'min.js'
            && APPLICATION_ENV == 'production') {

            $path = substr($path, 0, -3) . '.min.js';
        }

        // In production, use the minified CSS version
        if (substr($path, -4) == '.css' && substr($path, -7) !== 'min.css'
            && APPLICATION_ENV == 'production') {

            $path = substr($path, 0, -4) . '.min.css';
        }

        $hash = $this->_getCRC32($path);

        if (!preg_match('/^media./', $name)) {
            $name = 'media.' . $name;
        }

        $schemeHelper = new Zend_View_Helper_GetCurrentScheme();

        // Set the scheme the same as the current request
        $scheme = $schemeHelper->getCurrentScheme();
        $url    = $scheme . '://' . $name;
        if (strlen($hash)) {
            $url .= '/v/' . $hash;
        }
        $url .= $path;
        return $url;
    }

    /**
     * Calculates the CRC32 hash of a given static file
     *
     * @param string $path The path name to the file
     *
     * @return string
     */
    protected function _getCRC32($path)
    {
        $filename = BASE_PATH . '/public/media' . $path;

        if (!is_readable($filename)) {
            $log = EC_Log::getInstance();
            $log->crit('media file does not exist: ' . $filename);
            return;
        }

        $key   = md5('media_url' . $filename);
        $apc   = EC_Cache::singleton('apc');
        $hash = $apc->load($key);

        // If the hash was not found in APC, calculate it and store it for later
        if ($hash === false || APPLICATION_ENV == 'development') {
            $contents = file_get_contents($filename);

            // zero pad to 8 characters if necessary for our mod_rewrite regex
            $hash = sprintf('%08x', crc32($contents));
            if (APPLICATION_ENV == 'production') {
                $apc->save($hash, $key);
            }
        }

        return $hash;
    }
}