How to create configurable products?

[amitnayak1]

I am trying to create configurable products using below code and products array which is given in the demo module.

<?php
use \Magento\Framework\App\Bootstrap;
include('app/bootstrap.php');
$bootstrap = Bootstrap::create(BP, $_SERVER);
$objectManager = $bootstrap->getObjectManager();
$importModel = $objectManager->create('FireGento\FastSimpleImport\Model\Importer');

$products = [];
$products [] = [
    'sku' => "SIMPLE-BLUE-SMALL",
    'attribute_set_code' => 'Default',
    'product_type' => 'simple',
    'product_websites' => 'base',
    'name' => 'FireGento Simple Product Blue,Size Small',
    'price' => '1.0000',
    'color' => 'blue',
    'size' => 'S'
];
$products [] = [
    'sku' => "SIMPLE-RED-MIDDLE",
    'attribute_set_code' => 'Default',
    'product_type' => 'simple',
    'product_websites' => 'base',
    'name' => 'FireGento Simple Product Red,Size Middle',
    'price' => '1.0000',
    'color' => 'red',
    'size' => 'M'
];

$products [] = [
    'sku' => 'CONFIG-Product',
    'attribute_set_code' => 'Default',
    'product_type' => 'configurable',
    'product_websites' => 'base',
    'name' => 'FireGento Test Product Configurable',
    'price' => '10.000',
    'configurable_variation_labels' => 'Color',
    'configurable_variations' => [
        [
            'sku' => 'SIMPLE-BLUE-SMALL',
            'color' => 'blue',
            'size' => 'S'],
        [
            'sku' => 'SIMPLE-RED-MIDDLE',
            'color' => 'red',
            'size' => 'M'],
    ]

];
$importModel->processImport($products);
print_r($importModel->getLogTrace());
print_r($importModel->getErrorMessages());

It is giving the error

PHP Warning: explode() expects parameter 2 to be string, array given in /var/www/html/magento23/vendor/magento/module-configurable-import-export/Model/Import/Product/Type/Configurable.php on line 569

At line 569, below code is present.
$variations = explode(ImportProduct::PSEUDO_MULTI_LINE_SEPARATOR, $rowData['configurable_variations']);

How to create a configurable product? Magento version is 2.3.1

[erfanimani]

Have you tried writing it as a string instead of an array?

i.e. configurable_variations => 'sku=SIMPLE-BLUE-SMALL,color=blue,size=S\|sku=SIMPLE-RED-MIDDLE,color=red,size=M'

[norgeindian]

@amitnayak1 , you surely found a solution in the meantime, but maybe worth writing down the solution for others anyway.
This change from an array to the string, @erfanimani mentioned, can actually automatically be done, by including the NestedArrayAdapterFactory in the following way in your custom di.xml:

    <type name="FireGento\FastSimpleImport\Model\Importer">
        <arguments>
            <argument name="importAdapterFactory" xsi:type="object">FireGento\FastSimpleImport\Model\Adapters\NestedArrayAdapterFactory</argument>
        </arguments>
    </type>

Then, you can process the configurable variations like you did and they will be correctly transformed.