This document discusses strategies for integrating legacy applications into the Symfony framework. It describes using bundles to namespace the legacy code, autoloading to include the legacy files, and controllers to proxy requests to the legacy application. It also covers testing legacy functionality, using ESI and Varnish for caching parts of pages, and mapping legacy database tables to Doctrine entities. The goal is to modernize the application over time by rewriting specific functionality into Symfony while keeping the legacy system running.

1. LEGACY APPLICATIONS
Piotr Pasich

3. Piotr Pasich @
FROM SPAGHETTI TO CODE
czyli dziedziczymy aplikację

4. DLACZEGO TEGO NIE PRZEPISAĆ?
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5. dużo kodu
duża ilość funkcjonalności
czas
pieniądze
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6. PREVENTING REGRESSIONS
czyli nic nie ruszać
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7. TESTY FUNKCJONALNOŚCI
Selenium IDE, behat, testy jednostkowe
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8. ŚRODOWISKO
minimum PHP 5.3.3
Sqlite3, JSON, ctype
php app/check.php
date.timezone set in php.ini
Phpcs CodeSniffs
tutaj po raz pierwszy korzystamy z testów
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9. INSTALACJA SYMFONY 2
katalog legacy
namespace
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namespace Legacy {
(...)
}

10. LegacyBundle
app/console generate:bundle
Bundle namespace: XsolveLegacyBundle
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11. AUTOLOADER
<?php
namespace XsolveLegacyBundle;
require_once(__DIR__ . "/../../../legacy/index.php"); //disabled execute::run
use Legacy;
use SymfonyComponentHttpKernelBundleBundle;
use SymfonyComponentDependencyInjectionContainerBuilder;
class XsolveLegacyBundle extends Bundle
{
public function build(ContainerBuilder $container)
{
spl_autoload_register(array('Kohana', 'auto_load'));
}
}
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12. MainAction
class LegacyController extends Controller
{
/**
* @Route("/", name="main_page")
* @Route("/{filename}.html", name="proxy_html", requirements={"filename" = ".+"})
* @Route("/{filename}", name="proxy", requirements={"filename" = ".+"})
*/
public function indexAction($filename='index')
{
$_SERVER['SCRIPT_URL'] = $filename.'.html';
$_SERVER['REQUEST_URI'] = $filename.'.html';
ob_start();
// include_once ('../legacy/index.php');
Event::run('system.routing');
Benchmark::stop(SYSTEM_BENCHMARK.'_system_initialization');
Event::run('system.execute');
$response = new Response(ob_get_clean());
return $response;
}
}
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13. KOHANA?
system/core/Bootstrap.php
//Event::run('system.routing');
//Benchmark::stop(SYSTEM_BENCHMARK.'_system_initialization');
//Event::run('system.shutdown');
DIE; //!
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14. LAYOUT
esi
Varnish
Guzzle Client
Crawler
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15. ESI + VARNISH
http://todsul.com/symfony2-esi-varnish
framework: { esi: true }
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16. ESI CONTROLLER
/**
* @Route(name="esi_center_column")
*/
public function getCenterColumnAction(Request $request)
{
$url = $request->get('url'); //almost like proxy.php
$html = $this->get('xsolve.legacy.client')->requestElement($url, '.
span-center');
return $this->get('xsolve.response.cache')->getResponseWithCache
($html, 10);
}
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17. ESI SERVICE
class LegacyClient
{
(...)
public function requestElement($url, $element)
{
$html = $this->request($url);
return $this->filter($html, $element);
}
(...)
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18. ESI SERVICE
/**
* @return SymfonyComponentDomCrawlerCrawler
*/
public function request($url)
{
if (!isset($this->response[$url])) {
$client = $this->getClient();
$request = $client->get($url);
$request->setHeader('Cookie', null);
$this->response[$url] = $request->send();
}
return $this->response[$url]->getBody();
}
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19. ESI SERVICE
/**
* @return GuzzleHttpClient
*/
public function getClient()
{
$client = new Client();
return $client;
}
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20. ESI SERVICE
public function filter($html, $element)
{
$crawler = new Crawler();
$crawler->addHtmlContent($html);
$crawler = $crawler->filter($element);
$html = '';
foreach ($crawler as $domElement) {
$html.= $domElement->ownerDocument->saveHTML($domElement);
}
return $html;
}
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21. ESI SERVICE
public function filter($html, $element)
{
$crawler = new Crawler();
$crawler->addHtmlContent($html);
$crawler = $crawler->filter($element);
$html = '';
foreach ($crawler as $domElement) {
$html.= $domElement->ownerDocument->saveHTML($domElement);
}
return $html;
}
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22. HOW TO USE IT?
<!DOCTYPE html>
<html>
<esi:include src="{{ path('esi_head') }}" />
<body>
<div class="container with-background">
<esi:include src="{{ path('esi_left_column') }}" />
<div class="span-center">
{% block content %}
{% endblock %}
</div>
<esi:include src="{{ path('esi_right_column') }}" />
<esi:include src="{{ path('esi_footer') }}" />
</div>
</body>
</html>
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23. REVERSE PROXY CACHE
// app/AppCache.php
require_once __DIR__.'/AppKernel.php';
use SymfonyBundleFrameworkBundleHttpCacheHttpCache;
class AppCache extends HttpCache
{
protected function getOptions()
{
return array(
'debug' => false,
'default_ttl' => 0,
'private_headers' => array('Authorization', 'Cookie'),
'allow_reload' => true,
'allow_revalidate' => false,
'stale_while_revalidate' => 2,
'stale_if_error' => 60,
);
}
}
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24. REVERSE PROXY CACHE
<?php
// web/app.php
require_once __DIR__.'/../app/bootstrap.php.cache';
require_once __DIR__.'/../app/AppKernel.php';
require_once __DIR__.'/../app/AppCache.php';
use SymfonyComponentHttpFoundationRequest;
$kernel = new AppKernel('prod', false);
$kernel->loadClassCache();
// wrap the default AppKernel with the AppCache one
$kernel = new AppCache($kernel);
$request = Request::createFromGlobals();
$response = $kernel->handle($request);
$response->send();
$kernel->terminate($request, $response);
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25. REVERSE PROXY CACHE
class ResponseCache {
public function getResponseWithCache($html, $cacheTime=1)
{
$response = new Response($html);
$response->setMaxAge($cacheTime);
$response->setSharedMaxAge($cacheTime);
$date = new DateTime();
$date->modify("+$cacheTime seconds");
$response->setExpires($date);
return $response;
}
}
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26. RENDER
{% render url('latest_news', { 'max': 5 }) with {}, {'standalone': true} %}
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27. ROUTING
namespace XsolveLegacyBundleService;
class LegacyRouter
{
/** @var array Legacy routes configuration */
protected $config;
public function __construct(Router $router)
{
include __DIR__.'/../../../../legacy/application/config/urls.php';
$this->config = $config;
$this->router = $router;
$this->locale = $this->router->getContext()->getParameter('_locale');
}
// (..)
}
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28. KONFIGURACJA
class LegacyConfiguration
{
protected $configuration;
public function __construct($configuration)
{
$this->configuration = $configuration;
}
public function onKernelRequest(GetResponseEvent $event)
{
global $legacyConfig;
$legacyConfig = $this->configuration;
}
}
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29. KONFIGURACJA
global $legacyConfig;
$config['default'] = $legacyConfig['database']['default'];
$config['import'] = $legacyConfig['database']['import'];
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30. SESSION
Gdzie jest problem?
_s2_(...)
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31. SESSION
class RequestListener {
public function onKernelRequest(GetResponseEvent $event) {
$bags = array(
'total_hits',
'_kf_flash_',
'user_agent',
'last_activity',
'search.criteria',
'category.name',
'auth_user'
);
foreach ($bags as $namespace) {
$bag = new AttributeBag($namespace, '.');
$bag->setName($namespace);
$this->session->registerBag($bag);
}
}
}
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32. SESSION
namespace XsolveLegacyBundleSession;
use SymfonyComponentHttpFoundationSessionAttributeAttributeBagInterface;
use SymfonyComponentHttpFoundationSessionSessionBagInterface;
use XsolveLegacyBundleSessionScalarBagInterface;
/**
* This class provides scalar storage of session attributes using
* a name spacing character in the key.
*
* @author Piotr Pasich <piotr.pasich@xsolve.pl>
*/
class ScalarBag implements ScalarBagInterface, SessionBagInterface
{
// (...)
}
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33. REQUEST LISTENER
<?xml version="1.0" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.
com/schema/dic/services/services-1.0.xsd">
<services>
<service id="xsolve.legacy.listener.request" class="XsolveLegacyBundleRequestListener"
>
<tag name="kernel.event_listener" event="kernel.request" method="onKernelRequest"/>
<argument type="service" id="session" />
</service>
</services>
</container>
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34. NIE DZIAŁA!
DLACZEGO?
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35. BO KOHANA!
class Session_Core {
// (...)
public function create($vars = NULL)
{
$this->destroy();
// (...)
}
}
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36. TERAZ DZIAŁA
class Session_Core {
// (...)
public function create($vars = NULL)
{
//$this->destroy();
// (...)
}
}
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37. TERAZ NIE DZIAŁA
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38. TERAZ DZIAŁA
class Session_Core {
// (...)
public function create($vars = NULL)
{
// Destroy any current sessions
self::$createCall = self::$createCall+1;
if (self::$createCall > 10){
$_SESSION = array();
}
// this->destroy();
// (...)
}
}
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39. BAZA DANYCH
ponad 100 tabel = 100 encji
brak odpowiednich relacji
brak pełnej zgodności z wymogami Doctrine 2
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40. BAZA DANYCH
app/console doctrine:mapping:import XsolveLegacyBundle annotation
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41. KONFLIKTY I BŁĘDY
naprawiamy ręcznie :(
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42. PRZEPISUJEMY
/**
* @Route("/{categoryName}.html")
*/
public function indexAction($categoryName)
{
$criterias = array( 'category' => $categoryName );
$offers = $this->get('legacy.offers')->getRandomOffers($criterias);
$view = $this->renderView('XsolveOfferBundle:Default:index.html.twig', array(
'offers' => $offers
));
return $this->get('legacy.response.cache')->getResponseWithCache($view, 2);
}
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43. I TO DZIAŁA!
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44. DZIĘKUJĘ ZA UWAGĘ
Piotr Pasich
piotr.pasich@xsolve.pl
www.xsolve.pl