exchange/app/Console/Kernel.php

<?php

namespace App\Console;

use App\Http\Controllers\InvoiceController;
use App\InvoiceStatuses;
use Carbon\Carbon;
use Illuminate\Console\Scheduling\Schedule;
use Illuminate\Foundation\Console\Kernel as ConsoleKernel;
use Illuminate\Support\Facades\File;
use Illuminate\Support\Facades\Mail;
use ZipArchive;

class Kernel extends ConsoleKernel
{
    /**
     * The Artisan commands provided by your application.
     *
     * @var array
     */
    protected $commands = [
        //
    ];

    /**
     * Define the application's command schedule.
     *
     * @param  \Illuminate\Console\Scheduling\Schedule  $schedule
     * @return void
     */
    protected function schedule(Schedule $schedule)
    {
         $schedule->call(function(){
             $zipname = 'do_'.Carbon::today()->format('Y_m_d').'.zip';
             $zip = new ZipArchive;
             $zip->open($zipname, ZipArchive::CREATE);
             $approvedInvoices = InvoiceStatuses::where('status', 'approve')->whereDate('created_at', Carbon::today())->distinct()->get(['invoice_id']);
             $bookings = [];
             foreach($approvedInvoices as $approved){
                 $bookings[] = $approved->invoice->booking->id;
             }
             foreach ($bookings as $id) {
                 $do = app(InvoiceController::class)->generateSupplierDo($id);
                 $zip->addFromString('do_'.Carbon::today()->format('Y_m_d').'_'.$id.'.pdf', $do->Output('do.pdf', 'S'));
             }

             $zip->close();
             $attachment = public_path($zipname);

             Mail::raw( 'DO for bookings po approved on '.Carbon::today()->format('d/m/Y'), function($message) use ($attachment){
                 $message->from('exchange@cief-malaysia.com');
                 $message->to('uldvstar@gmail.com');
                 $message->subject('DO for bookings on '.Carbon::today()->format('d/m/Y'));

                 $message->attach($attachment);
             });

             File::delete($zipname);
         })->everyMinute();
    }

    /**
     * Register the commands for the application.
     *
     * @return void
     */
    protected function commands()
    {
        $this->load(__DIR__.'/Commands');

        require base_path('routes/console.php');
    }
}