$command = 'node ./node_modules/lighthouse/lighthouse-cli/index.js --chrome-flags="--headless" ' . $config . ' ' . $this->clientObj->clienturl;

    $aResult['res'] = exec($command . ' 2>&1', $aResult['output'], $aResult['return']);

--output-path=./lighthouse/report.json --output json

$command = 'lighthouse --chrome-flags="--headless" ' . $config . ' ' . $this->clientObj->clienturl;

'lighthouse' is not recognized as an internal or external command, operable program or batch file.