invoiceninja/app/Jobs/Cron/SubscriptionCron.php

<?php
/**
 * Invoice Ninja (https://invoiceninja.com).
 *
 * @link https://github.com/invoiceninja/invoiceninja source repository
 *
 * @copyright Copyright (c) 2021. Invoice Ninja LLC (https://invoiceninja.com)
 *
 * @license https://www.elastic.co/licensing/elastic-license
 */

namespace App\Jobs\Cron;

use App\Libraries\MultiDB;
use App\Models\Invoice;
use App\Utils\Traits\SubscriptionHooker;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Support\Carbon;

class SubscriptionCron
{
    use Dispatchable;
    use SubscriptionHooker;
    /**
     * Create a new job instance.
     *
     * @return void
     */
    public function __construct()
    {
    }

    /**
     * Execute the job.
     *
     * @return void
     */
    public function handle() : void
    {

        if (! config('ninja.db.multi_db_enabled')) {

            $this->loopSubscriptions();

        } else {
            //multiDB environment, need to
            foreach (MultiDB::$dbs as $db) {

                MultiDB::setDB($db);

                $this->loopSubscriptions();

            }
        }
        
    }

    private function loopSubscriptions()
    {

        $invoices = Invoice::where('is_deleted', 0)
                          ->whereIn('status_id', [Invoice::STATUS_SENT, Invoice::STATUS_PARTIAL])
                          ->where('balance', '>', 0)
                          ->whereDate('due_date', '<=', now()->addDay()->startOfDay())
                          ->whereNull('deleted_at')
                          ->whereNotNull('subscription_id')
                          ->cursor();


        $invoices->each(function ($invoice){

            $subscription = $invoice->subscription;

            $body = [
              'context' => 'plan_expired',
              'client' => $invoice->client->hashed_id,
              'invoice' => $invoice->hashed_id,
              'subscription' => $subscription->hashed_id,
            ];

            $this->sendLoad($subscription, $body);
            //This will send the notification daily. 
            //We'll need to handle this by performing some action on the invoice to either archive it or delete it?
        });

    }


    private function handleWebhook($invoice, $subscription)
    {

    }
    
}