Example of Database Transactions in devhub-az/devhub

File app/Http/Controllers/Api/ArticleController.php (link to Github)

use App\Http\Controllers\Controller;
use Illuminate\Support\Facades\DB;

class ArticleController extends Controller
{
    //
    public static function upOrDownVote(User $user, $target, string $type = 'up'): bool
    {
        $hasVoted = $user->{'has'.ucfirst($type).'Voted'}($target);
        DB::beginTransaction();

        try {
            $user->{$type.'Vote'}($target);
            if ($hasVoted) {
                $user->cancelVote($target);
                foreach ($target->hubs as $hub) {
                    $type === 'up' ? $hub->rating-- : $hub->rating++;
                    $hub->save();
                }
                $type === 'up' ? $target->creator->rating-- : $target->creator->rating++;
                $target->author->save();
                DB::commit();

                return false;
            }
            foreach ($target->hubs as $hub) {
                $type === 'up' ? $hub->rating++ : $hub->rating--;
                $hub->save();
            }
            $type === 'up' ? $target->creator->rating++ : $target->creator->rating--;
            $target->author->save();
            DB::commit();
        } catch (Exception $e) {
            DB::rollback();
            abort(500);
        }

        return true;
    }
}