Laravel batch file upload - laravel-5

Question

I have a csv file with the following structure:
id,title,sub_title,filename
1,Title 1, Sub Title 1,filename_1.mp3
2,Title 2, Sub Title 2,filename_2.mp3
3,Title 3, Sub Title 3,filename_3.mp3
(...)
I'm loading the CSV file inside a App\Console\Command (artisan command).
Assuming the files exist on the filesystem and the path is correct, for each csv line how can I upload the related file and validate it using the Validator class?
I'm using this code:
$validator = Validator::make(array('filename' => 'path_to_filename_x.mp3'), [
'filename' => 'required|file|audio:mp3,wav,ogg',
]);
if ($validator->fails()) {
echo '<pre>';
print_r($validator->errors());
echo '</pre>';
die();
}
I'm getting the error:
"The attribute must be a file."
Because I'm sending text instead of a resource (i suppose).
How can I upload these files without using a form using Laravel 5.6?
Thks!

Answer 1

Question: how can I upload the related file and validate it using the Validator class?
Validating the files:
Create a custom rule in laravel and there you can add logic like.
if(file_exists($path)){
//check for file type
}
Upload the files :
use $fcontent = file_get_contents($filepath) and file_put_contents($newfilepath, $fcontent)