public function read($key, $next)
    {
        $session_key = $this->sanitize($key);

        $data = wp_cache_get("session_${session_key}", 'sessions');
        if (false === $data) {
            // Passing the key unsanitized to the next handler to avoid weirdness.
            $data = $next($key);
            if (false !== $data) {
                wp_cache_set("session_${session_key}", $data, 'sessions', $this->getExpiration());
            }
        }

        return $data;
    }