ConvertURLActivity.php

<?php

namespace App\Workflows\BuildPDF;

use Illuminate\Support\Facades\Http;
use Workflow\Activity;

class ConvertURLActivity extends Activity
{
    public function execute($url)
    {
        $fileName = uniqid() . '.pdf';

        Http::withHeaders([
            'Apikey' => 'YOUR-API-KEY-GOES-HERE',
        ])
        ->withOptions([
            'sink' => storage_path($fileName),
        ])
        ->post('https://api.cloudmersive.com/convert/web/url/to/pdf', [
            'Url' => $url,
        ]);

        return $fileName;
    }
}