liwo/database/factories/FileFactory.php

<?php

/** @var Factory $factory */

use App\File;
use Faker\Generator as Faker;

$factory->define(File::class, function (Faker $faker) {
    $mimes = ['application/pdf', 'video/mp4', 'image/png', 'image/jpeg', 'audio/x-wav'];
    $extensions = ['pdf', 'mp4', 'png', 'jpg', 'wav'];
    $groups = [
        'pdf' => 'pdf',
        'mp4' => 'video',
        'png' => 'image',
        'jpg' => 'image',
        'wav' => 'audio',
    ];
    $sizes = [1, 5, 128, 256, 1024, 2048];
    $rand_type = $faker->numberBetween(0, 4);
    return [
        'user_id' => $faker->numberBetween(1, 200),
        'business_id' => $faker->numberBetween(1, 200),
        'project_id' => $faker->numberBetween(1, 200),
        'attached_to_id' => $faker->numberBetween(1, 100),
        'attached_to_table' => enum('tables.tasks.id'),
        'disk' => 's3',
        'original_name' => $faker->words(1, true),
        'name' => $faker->words(1, true),
        'extension' =>  $extension = $extensions[$rand_type],
        'mime' => $mimes[$rand_type],
        'group' => $groups[$extension],
        'size' => $sizes[$faker->numberBetween(0, 5)],
        'description' => $faker->text,
    ];
});