phparchitect-2019-08

22 \ August 2019 \ http://www.phparch.com

Can You Migrate Any Legacy Code Under One Month?

• It might take months and bring
  zero value to the business.
  If I owned the business, all I would
  hear, “We want to play, give us your
  money for an uncertain amount of
  time, and you’ll get nothing of value in
  return.”
  That’s the problem, as programmers,
  we only get money for the time spent
  at work. When we go home at the end
  of the day, we don’t care if the business
  lasts through the next summer.
  We care about ourselves. We pay rent
  and expect to live for the next year with
  the same quality, we pay for Spotify
  and expect it to give us enjoyable songs
  for the long term. The business owner
  is like us—they pay us monthly and
  expect long term sustainability.
  We need to learn to make a business
  case for the value of migrating to a new
  framework or language version.

How to be One with the Busi-
ness?
Rector is not a tool to play and
migrate code just because it can. It
needs to bring value to the business.
That’s why we need a mind shift from
“must-have” to “it’s better”:

• When we migrate from Zend 1 to
  Symfony 4 in 30 days, we’ll lose a
  month of work of two people, but
  the delivery time for our tasks will
  drop from four hours to 30 minutes.
  In three months, we have it paid for,
  and then we profit.


• Upgrading from PHP 5.6 to PHP
  7.3 allows us to run 50% fewer
  servers and to scale better at traffic
  peaks."


• "When we use Symfony, it stream-
  lines hiring new developers. Last
  month we had a meeting with one
  Zend developer, but six Symfony
  developers. (True story.)


• The Symfony community is much
  more active than Zend in our coun-
  try, by the numbers it’s 12 meetups
  a year to zero meetups. It’s easier to

7 NEON: https://ne-on.org/

8 YAML: https://yaml.org/

learn and to share our know-how

there, which eventually brings us

more developers, with a better team

and code quality, therefore, cheaper

feature delivery.

With this in mind, we started the

migration from Nette to Symfony.

Instant Migration with Rector

What were the patterns we needed to

migrate? Output 1 and Output 2 shows

a diff of some migrations. We had

to update the following libraries and

patterns.

• NEON^7 to YAML^8 for the configu-
  ration system.

Output 1

1. <?php declare (strict_types = 1);


2. 
   


3. -namespace App\Presenter;


4. +namespace App\Controller;


5. 
   


6. -use Nette\Application\AI\Presenter;


7. +use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;


8. -use Nette\Http\Request;


9. +use Symfony\Component\HttpFoundation\Request;


10. 
    


11. -final class SomePresenter extends Presenter


12. +final class SomeController extends AbstractController


13. {


14. 
    
    
    
    • public static function someAction()
    
    
    
    


15. 
    
    
    
    • public static function someAction(Request $request)
    
    
    
    


16. {


17. 
    
    
    
    • $header = $this->httpRequest->getHeader('x');
    
    
    
    


18. 
    
    
    
    • $header = $request->headers->get('x');
    
    
    
    


19. 
    


20. 
    
    
    
    • $method = Request::POST;
    
    
    
    


21. 
    
    
    
    • $method = Request::METHOD_POST
    
    
    
    


22. }


23. }

Output 2

1. <?php


2. 
   


3. namespace App;


4. 
   


5. use Entrydo\RestRouteList;


6. use Entrydo\Restart;


7. 
   


8. final class RouterFactory


9. {


10. 
    
    
    
    • private const PAYMENT_RESPONSE_ROUTE = '/payment/process';
    
    
    
    


11. // 150 more!


12. 
    


13. public function create()


14. {


15. $router = new RestRouteList();


16. 
    
    
    
    • $router[] = RestRoute::get(self::PAYMENT_RESPONSE_ROUTE,
      ProcessGPWebPayResponsePresenter::class);
    
    
    
    


17. // 150 more!


18. 
    


19. return $router;


20. }


21. }