SPOUT

<?php namespace ProcessWire;

require($config->paths->templates . 'Spout/Autoloader/autoload.php');



use Box\Spout\Writer\WriterFactory;
use Box\Spout\Common\Type;



class export {

	// PageArray
	private $products = null;

	// PageArray
	private $limit = 10;
	// Current
	private $start = 0;
	// Is new?
	private $isNew = null;

	private $fp = null;
	private $writer = null;

	public function __construct() {
		$this->total = 5 * $this->limit;
	}

	// Create file
	private function createFile() {
		$base = wire('config')->paths->templates;
		$path = $base . date('Ydm H:i:s') . '.xlsx';
		$this->fp = fopen($path, 'a');
		$this->writer = WriterFactory::create(Type::XLSX);
		$this->writer->openToFile($path);
		$this->isNew = false;
	}

	public function run() {

		do {

			if ($this->isNew === null) $this->createFile();

			$this->products = wire('pages')->find('template=product, start=' . $this->start . ', limit=' . $this->limit);
			$this->start += $this->limit;

			foreach ($this->products as $p) {
				$this->writer->addRow(array($p->id, $p->title));
			}


		} while($this->start < $this->total);


		$this->writer->close();
		fclose($this->fp);
	}
}




$export = new export();
$export->run();