Magento2 Sandbox Script - http://www.blog.magepsycho.com/sandbox-script-quick-testing-magento2/

Magento2-Sandbox-Script.php

<?php

####################################################
# EDIT
$rootMagentoDir = __DIR__;
#$csvFile = $rootMagentoDir . '/update_skus.csv';
$logFile = $rootMagentoDir . '/var/log/cli-operation.log';
$dryRun = 0;
####################################################

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);

// Capture warning / notice as exception
set_error_handler('sqli_exceptions_error_handler');
function sqli_exceptions_error_handler($severity, $message, $filename, $lineno)
{
    if (error_reporting() == 0) {
        return;
    }
    if (error_reporting() & $severity) {
        throw new ErrorException($message, 0, $severity, $filename, $lineno);
    }
}

function _log($data, $includeSep = false)
{
    global $logFile;
    $fileName = $logFile;
    if ($includeSep) {
        $separator = str_repeat('=', 70);
        file_put_contents($fileName, $separator . PHP_EOL,  FILE_APPEND | LOCK_EX);
    }
    file_put_contents($fileName, $data . PHP_EOL,  FILE_APPEND | LOCK_EX);
}

function _getConnection()
{
    global $obj;
    $resource = $obj->get('Magento\Framework\App\ResourceConnection');
    return $resource->getConnection();
}

function _getSkus()
{
    $connection = _getConnection();
    $sql = "SELECT sku, entity_id FROM catalog_product_entity WHERE created_in = 1;";
    return $connection->fetchPairs($sql);
}

function _readCsvRows($csvFile)
{
    $rows = [];
    $fileHandle = fopen($csvFile, 'r');
    while(($row = fgetcsv($fileHandle, 0, ',', '"', '"')) !== false) {
        $rows[] = $row;
    }
    fclose($fileHandle);
    return $rows;
}

require $rootMagentoDir . '/app/bootstrap.php';
$bootstrap = \Magento\Framework\App\Bootstrap::create(BP, $_SERVER);
$obj = $bootstrap->getObjectManager();
$state = $obj->get('Magento\Framework\App\State');
$state->setAreaCode('crontab');

try {
    
    $message = 'Success::Operation Completed.';
    #_log($message);
    echo $message . PHP_EOL;
} catch (Exception $e) {
    $message = 'Exception::' . $e->getMessage();
    #_log($message);
    echo $message . PHP_EOL;
}