M1-export.php

<?php

require_once '../abstract.php';

class Namespace_ProductExport extends Mage_Shell_Abstract
{
    protected $_io;
    protected $_folder       = 'exports';
    protected $_name         = 'ProductExport.csv';
    protected $_delimiter    = ',';
    protected $_attributeMap = array(
        'ProductSku' => 'sku',   // 1
        'ChildProductSku' => 'children', //2
        'SupplierRef'  => 'supplier', // 3
        'ProductImage'  => 'image', // 4
        'Brand'  => 'brand_category', // 5
        'ProductName'  => 'name', // 6
        'Description'  => 'description', // 7
        'Size'  => 'size', // 8
        'Category'  => 'category_ids', //9
        'Colour'  => 'colour', // 10
        'Gender'  => 'gender', // 11
        'Quantity'  => 'qty' // 12
    );

    protected function _construct()
    {
        $this->_io = new Varien_Io_File();
        $this->_io->setAllowCreateFolders(true);

        parent::_construct();
    }

    public function run()
    {
        $productsCollection = Mage::getModel('catalog/product')->getCollection()
            ->addAttributeToSelect('*');

        $productsCollection->setPageSize(100)->setCurPage(1);

        $pages = $productsCollection->getLastPageNumber();

        $currentPage = 1;

        $this->_io->open(array('path' => $this->_folder));
        $this->_io->streamOpen($this->_name);
        $this->_io->streamWrite($this->_convertArrayToDelimitedString(array_keys($this->_attributeMap)) . "\r\n");

        do {
            $productsCollection->setCurPage($currentPage);

            foreach ($productsCollection as $_product) {
                $mappedValues = $this->_getMappedValues($_product);
                print_r($mappedValues);
                die('1 record');
                if (!empty($mappedValues)) {
                    $this->_io->streamWrite($this->_convertArrayToDelimitedString($mappedValues) . "\r\n");
                }
            }

            $currentPage++;
            $productsCollection->clear();
        } while ($currentPage <= $pages);

        $this->_io->streamClose();
    }

    protected function _convertArrayToDelimitedString($data)
    {
        return implode($this->_delimiter, $data);
    }

    protected function _getMappedValues($product)
    {
        $data = array();

        foreach ($this->_attributeMap as $column => $attribute) {
            $data[] = $product->getData($attribute);
        }

        return $data;
    }

}

// Create a new instance of our class and run it.
$shell = new Namespace_ProductExport();
$shell->run();