Sonata\Exporter\Writer\GsaFeedWriter::generateNewPart PHP Метод

    private function generateNewPart()
    {
        if ($this->buffer) {
            $this->closeFeed();
        }
        $this->bufferSize = 0;
        ++$this->bufferPart;
        if (!is_writable($this->folder)) {
            throw new \RuntimeException(sprintf('Unable to write to folder: %s', $this->folder));
        }
        $this->buffer = fopen(sprintf('%s/feed_%05d.xml', $this->folder, $this->bufferPart), 'w');
        $this->bufferSize += fwrite($this->buffer, <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE gsafeed PUBLIC "-//Google//DTD GSA Feeds//EN" "{$this->dtd}">
<gsafeed>
    <header>
        <datasource>{$this->datasource}</datasource>
        <feedtype>{$this->feedtype}</feedtype>
    </header>

    <group>

XML
);
    }