Refactor Magento 1 Super Attributes Into Magento 2 Suitable Format

refactor.php

<?php
/*
* USING EXCEL
* 1) Grab the export from Magento
* 2) Filter the blanks out of "Super Attributes SKU" column 
* 3) Copy columns sku	_super_products_sku	_super_attribute_code	_super_attribute_option into new sheet
* 4) Save it in same directory as this script and run.
* 5) Refactored feed will be generated.
*/
?>
<style>
    td {
        border-bottom: 1px solid #ccc;}
    td.found {background-color:#00ff00;}
    td.nofound {background-color:#ff0000;}
</style>
<?php
function readCSV($csvFile){
    $file_handle = fopen($csvFile, 'r');
    while (!feof($file_handle) ) {
        $line_of_text[] = fgetcsv($file_handle, 0);
    }
    fclose($file_handle);
    return $line_of_text;
}
function _group_by($array, $key) {
    $return = array();
    foreach($array as $val) {
        $return[$val[$key]][] = $val;
    }
    return $return;
}
function recombobulate($array){
    $skuFull = array();
    foreach ($array as $row){ //Each sku
        //var_dump($row);
        $skuOptions = array();
        foreach($row AS $options){ //Each sku's options
            //var_dump($options);
            //Take SKU and use as key
            //Take code and opt, put them into array.
            array_push($skuOptions,$options["code"] . "=\"" . $options["opt"] . "\"");
            $sku = "sku=" .  $options["sku"];
        }
        array_unshift($skuOptions,$sku);
        //Make sure to set semicolon as the "Multiple Value Separator" in firebear, otherwise the sku won't be picked up.
        $optionsCombined = implode(";",$skuOptions);
        array_push($skuFull,$optionsCombined);
    }
    return $skuFull;
}

$csvOut = "sku,attribute_set_code,configurable_variations\n";


$csv = readCSV('feed.csv'); 
// Unquote echos to show in tabular format while running
//echo "<table><th>SKU</th><th>Conf</th>";
$counter = 0;

$csvArray = array();
array_push($csvArray,array("sku","attribute_set_code","configurable_variations"));
$lastSku = "";
foreach ( $csv as $c ) {

    if($counter > 0) {
//        echo "<tr>";
        if($c[0] != ""){
            $sku = $c[0];
        }

        $supSKU = $c[1];
        $supCode = $c[2];
        $supOpt = $c[3];

//        echo "<td>" . $sku . "</td>";
//        echo "<td>";

        if($sku != $lastSku) { //Start New Product

            $grouped = _group_by($confArray, 'sku');
            $combined = recombobulate($grouped);
            var_dump($combined);
            array_push($csvArray, array($lastSku, "Default", implode("|", $combined)));
            $confArray = array();
        }

            //We need to push $supSKU to a key in array and any subsequent values go into that.

           $confRecord = array(
             "sku"  => $supSKU,
             "code" => $supCode,
             "opt"  => $supOpt
           );

            array_push($confArray, $confRecord);


        $lastSku = $sku;
    }
    $counter++;
}

?>
<!--</table>-->
<?php


$csv_handler = fopen ('refactored.csv','w');
foreach($csvArray AS $toGo){
    fputcsv($csv_handler,$toGo);
}
fclose ($csv_handler);

I wanted to paste this here because it could be very useful to those who need to migrate Magento 1 products without using the migration tool. I usually use Firebear Import/Export for this purpose, but it might be useful for other platforms.

Here's my gist for additional images https://gist.github.com/thomas-harding/5211913c429d0fb6655e4ff7b7934e01