An Introduction to Symfony Components and the Symfony2 Framework.

1. An Introduction to
Christian Zenker @xopn mail@xopn.de

2. Symfony Components
● About 20 stand-alone packages with one specific purpose
● Mostly independent from each other
● Usable in almost any PHP project
● Unit tested and well documented
http://symfony.com/components

3. ● YAML is a human-readable data
serialization format like XML or
JSON
YAML Component
user:
name: Homer Simpson
# unsure about age
age: 40
kids: ["Bart", "Lisa", "Maggie"]
quotes:
- |
Operator! Give me the
number for 911!
- |
Internet? Is that thing
still around?"
http://symfony.com/doc/current/components/console/introduction.html
$yaml =
file_get_contents('users.yml');
$parser = new Parser();
$data = $parser->parse($yaml);
$data['user']['wife'] = 'Marge';
$dumper = new Dumper();
$yaml = $dumper->dump($data, 2);
file_put_contents(
'users.yml', $data
);

4. Console Component
● Write console programs in PHP
● Clean architecture
● Parses arguments and options
● Easily extensible
● Helpers for
– progress bars
– tabular data
– interactive questions
– colored output
me@home> php console.php demo:hello John
Hello John
me@home> php console.php demo:hello
What's your name? John
Hello John
me@home> php sandwich.php make
What? Make it yourself!
me@home> php sandwich.php make --force
Ok.
[=======>---------] 42%

5. Console Component (II)
class GreetCommand extends Command {
protected function configure() {
$this
->setName('demo:greet')
->setDescription('Greet someone')
->addArgument(
'name',
InputArgument::OPTIONAL,
'Who do you want to greet?'
)
->addOption(
'yell',
null,
InputOption::VALUE_NONE,
'If set, the task will yell in uppercase letters'
)
;
}
// ...

6. Console Component (III)
// ...
protected function execute(InputInterface $input, OutputInterface $output) {
$name = $input->getArgument('name');
if ($name) {
$text = 'Hello '.$name;
} else {
$text = 'Hello';
}
if ($input->getOption('yell')) {
$text = strtoupper($text);
}
$output->writeln($text);
}
}
http://symfony.com/doc/current/components/console/introduction.html

7. Finder Component
http://symfony.com/doc/current/components/finder.html
http://symfony.com/doc/current/components/filesystem.html
● Simple wrapper for PHP functions
● Exceptions on error
● Batch processing$finder = new Finder();
$iterator = $finder
->files()
->name('*.php')
->depth(0)
->size('>= 1K')
->in(__DIR__);
foreach ($iterator as $file) {
/** @var SplFileInfo $file */
$file->getRealpath();
}
● Search filesystem or Amazon S3
● Uses `find` or PHP functions
$filesystem = new Filesystem();
$filesystem->mkdir($dirs, 0777);
$filesystem->touch($files, time() - 86400);
$filesystem->remove($dir);
$filesystem->chown($files, $user);
$filesystem->symlink($originDir, $targetDir);
$filesystem->mirror($originDir,$targetDir);
Filesystem Component

8. CssSelector Component
● Converts CSS selectors into Xpath ● Query XML and HTML pages
● Use for simple functional tests
Goutte
echo CssSelector::toXPath('div.item > h4 > a');
descendant-or-self::div[contains(
concat(' ',normalize-space(@class), ' '),
' item ')]/h4/a
https://github.com/fabpot/Goutte
http://symfony.com/doc/current/components/css_selector.html
$client = new Client();
$crawler = $client->request(
'GET', 'http://example.com'
);
$link = $crawler->selectLink('Users')->link();
$crawler = $client->click($link);
$users = $crawler->filter('#users > li');
echo count($users) . ' online';
● CSS is better readable
● Xpath is more powerful

9. Symfony Framework
● an HTTP framework
● MVC framework? Sure, why not.
● Based on Symfony Components
and well-established third-party
libraries
● Backwards compatibility starting
with 2.3
● Console powered
● Environment aware (production,
development, testing)
● Configuration via YAML, XML,
JSON, annotations
● Fast and low memory footprint

10. ClassLoader
Config
Console
DependencyInjection
EventDispatcher
Finder
Form
HttpFoundation
HttpKernel
Intl
Routing
Security
Validator
...
SF Components
SwiftMailer
Doctrine
Monolog
Assetic
Twig
FrameworkBundle
SwiftmailerBundle
GeneratorBundle
DoctrineBundle
WebProfiler
Bundle
AsseticBundle Security
Bundle
...
...

11. GET / HTTP/1.1
Host: example.com
Accept: text/html
HTTP/1.1 200 OK
Content-Type: text/html
<!DOCTYPE html>
<p>Hello World</p>
Browser

12. GET / HTTP/1.1
HTTP/1.1 200 OK
Application
index.php
Symfony2 Kernel
Routing
Request URI
Controller::action
Request
Object
Response
Object

13. GET / HTTP/1.1
HTTP/1.1 200 OK
Application
index.php
Symfony2 Kernel
Routing
Request URI
Controller::action
Request
Object
Response
Object
Firewall
Caching
Event Handling

14. Controller
class MainController extends Controller {
public function helloAction($name) {
return $this->render(
'AcmeHelloBundle:Main:hello.html.twig',
array('name' => $name)
);
}
}
hello:
path: /hello/{name}
defaults:
_controller: AcmeHelloBundle:Main:hello
http://example.com/hello/world
<!DOCTYPE html>
<h1>Hello {{ name }}!</h1>
<p>Also see our
<a href="{{ path('route_name') }}">
other pages
</a>
</p>
<ul>
{% for i in 0..10 if i %2 == 0 %}
<li>{{ i }} is an even number</li>
{% endfor %}
</ul>

15. Service Container
class AntispamService {
/** doctrine entity manager */
protected $em;
protected $max;
public function __construct($em, $max) {
$this->em = $em;
$this->max = $max
}
public function isCommentSpam($string) {
$words = explode(' ', $string);
$dql = 'SELECT w FROM AcmeHelloBundle:Word WHERE w.word IN (?)';
$query = $this->em->createQuery($dql);
$query->setParameter(0, $words);
$blackWords = $query->execute();
return count($blackWords) > $this->max;
}
}

16. Service Container (II)
services:
acme_hello.antispam:
class: AcmeHelloBundleAntispamService
arguments:
- @doctrine.orm.entity_manager
- %max_blacklist_words%
public function indexAction($comment) {
$service = $this->get('acme_hello.antispam');
if($service->isCommentSpam()) {
$response = new Response();
$response->setStatusCode('403');
$response->setContent('Get off my lawn');
return $response;
}
// ... do something ...
}

17. Further Reading
● symfony.com
– Official homepage with
documentation, etc.
● fabien.potencier.org
– The fancy parts
● silex.sensiolabs.org
– Microframework (the missing link
between Components and
Framework)
● knpbundles.com
– Database with additional bundles
– StofDoctrineExtensionsBundle
– LiipImagineBundle
– FOQElasticaBundle
– DoctrineFixturesBundle

18. ?Questions?

19. !Thank you for your
attention
Christian Zenker
AOE GmbH
http://xopn.de
mail@xopn.de
Twitter @xopn