Yii2: Get a temporary file

/*****************************************
 * Put somewhere this code, then call it
 *****************************************/

/**
 * Create a temp file and get full path
 * @param string $prefix (optional) Name prefix
 * @return string Full temp file path
 * @throws \yii\web\NotFoundHttpException When tmp directory doesn't exist or failed to create
 */
function getTempFile ( $prefix = 'temp' ) {
	$tmpDir = \Yii::$app->runtimePath.'/tmp';

	if ( !is_dir($tmpDir) && (!@mkdir($tmpDir) && !is_dir($tmpDir)) ) {
		throw new \yii\web\NotFoundHttpException ('temp directory does not exist');
	}

	return tempnam( $tmpDir, $prefix );
}

/*******************
 * EXAMPLE OF USAGE
 *******************/

// absolute temp file path
$tmpFile = getTempFile();

/** @var string $contents */
$contents = <<<CONTENTS
Lorem ipsum dolor sit amet, tritani abhorreant in sea, wisi vitae disputationi ad eam, tacimates molestiae adolescens sed at.
CONTENTS;

/** @var string $file */
file_put_contents( $tmpFile, $contents );

// remove the file
@unlink($tmpFile);