eZ\Publish\Core\IO\IOService::removeUriPrefix PHP Method

    protected function removeUriPrefix($spiBinaryFileId)
    {
        if (!isset($this->settings['prefix'])) {
            return $spiBinaryFileId;
        }
        if (strpos($spiBinaryFileId, $this->settings['prefix'] . '/') !== 0) {
            throw new InvalidBinaryPrefixException($spiBinaryFileId);
        }
        return substr($spiBinaryFileId, strlen($this->settings['prefix']) + 1);
    }