Symfony 2 basics

Maxence POUTORD

@_maxpou | maxpou.fr | maxence.poutord@gmail.com

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PHP OOP

POPO: Plain Old PHP Object

class Drink
{
  protected $id;
  protected $name;
  protected $description;

  public function __construct() {
    //...
  }
}

class Beer extends Drink
{
  protected $alcohol;
  protected $color;
  protected $type;

  public function __construct() {
    //...
  }

  public function drinkIt() {
    echo "glug glug";
  }
}

Getter/Setter

class Beer
{
  private $color;
  //...

  public function getColor() {
      return $this->id;
  }

  public function setColor($color) {
    $this->color = $color;
  }
}

Instanciate new class

class Beer
{
  //...
}
$myBeer = new Beer();
$myBeer->drinkIt(); //will output "glug glug"
$myBeer->setColor("blond");
$color = $myBeer->getColor();

Visibility

• public
• protected
• private

Further reading

• OOP Basic
• Namespaces
• Codecademy "PHP OOP"

Design Anti-Pattern: Singleton

class MySingleton
{
    protected static $instance;
    protected function __construct() { }

    public static function getInstance()
    {
        if (!isset(self::$instance)) {
            self::$instance = new self;
        }

      return self::$instance;
    }
}

Design Pattern: Dependency Injection

Hollywood Principle: "Don't call us, we'll call you"

Why should I use Framework ?

• Velocity: work better (structuring developments) & faster (reusing generic modules, code generation...)
• Facilitate long-term maintenance
• Improve security

Why Symfony2 ?

• #1 in France ( employment)
• Use best practices
• Open Source
• Bundle: reusable components
• Debug toolbar (killer feature)

Projects using Symfony: Drupal, Laravel, eZ Publish, Magento, BlaBlaCar, You****(You-Know-Who)

Symfony2

What is Symfony2 ?

Bundle concept

• Bundle = Plugin
• "Everything is a bundle in Symfony"

Symfony2 MVC approach

So, Symfony2 is a MVC Framwork ? NO!

Composer

• Tool for dependency management in PHP (Like node's npm, ruby's bundler...)

RTFM

• Level 0: The Symfony Book
• Level 1: The Symfony Cookbook
• Level 2: Symfony Best Practices

Getting started

# 1. install Symfony Installer (Linux/OS X)
$ sudo curl -LsS http://symfony.com/installer -o /usr/local/bin/symfony
$ sudo chmod a+x /usr/local/bin/symfony
# 1. install Symfony Installer (Windows)
$ php -r "file_put_contents('symfony', file_get_contents('http://symfony.com/installer'));"

# Download&Install Symfony
$ symfony new beerApp
# OR (choose a version)
$ symfony new beerApp 2.8

# 3. Create the first bundle
$ php app/console generate:bundle --format=yml

Symfony 2 Architecture

4 Folders:

• app: application configuration, layout templates...
  • AppKernel.php: register bundle
• src: project's PHP code (yours bundles)
• vendor: Dependencies (other bundles) - Read only !
• web: web root directory
  • app.php: production endpoint
  • app_dev.php: development endpoint

Symfony2's components

Controller

Request to Response

Routing

# app/config/routing
conserto_beer:
    resource: "@ConsertoBeerBundle/Resources/config/routing.yml"
    prefix:   /

# src/Conserto/BeerBundle/Resources/config/routing.yml
conserto_beer_show:
    path:     /{id}/show
    defaults: { _controller: "ConsertoBeerBundle:Beer:show" }

conserto_beer_update:
    path:     /{id}/update
    defaults: { _controller: "ConsertoBeerBundle:Beer:update" }
    methods:  [POST, PUT]

Lost ?

$ php app/console debug:router
$ php app/console router:match /beer/4/show

Routing advanced

beer_show:
  path:     /beers/{_locale}/{brand}/{name}.{_format}
  defaults: { _controller: ConsertoBundle:Beer:show, _format: html }
  schemes:  [https]
  requirements:
      _locale:  en|fr
      _format:  html|rss
      year:     \d+

Routing (Symfony Book)

Twig

In a nutshell:

• PHP/HTML separation
• More readable syntax
• Add security
• Fully documented (http://twig.sensiolabs.org)

//Before
<p><?php echo $var; ?></p>

{# After #}
<p>{{ var }}</p>

Twig: before/after

<!-- Before -->
<ul>
<?php
if (count($beers) > 0) {
    foreach ($beers as $aBeer) {
        echo "<li>".$aBeer->name." have ".$aBeer->alcohol." alcohol degree</li>";
    }
} else {
    echo "<li><em>no beer found</em></li>";
}
?>
</ul>

<!-- After -->
<ul>
    {% for aBeer in beers %}
        <li>{{ aBeer.name }} have {{ aBeer.alcohol }} alcohol degree</li>
    {% else %}
        <li><em>no beer found</em></li>
    {% endfor %}
</ul>

TWIG: filters

{{ "now"|date("m/d/Y") }} // 2/11/2015

{{ 'abcd...'|reverse }} //...dcba

{{ '12345'|slice(1, 2) }} //23

{{ 101.51|round }} //102

{# Multiple filters #}
{{ 'abcd...'|slice(1, 2)|reverse }} //cb

TWIG: Functions

{{ path('conserto_beer') }}
{{ path('conserto_beer_show', { 'id': 42 }) }}
{{ path('conserto_beer_show', { 'id': entity.id }) }}

<link rel="icon" type="image/x-icon" href="{{ asset('favicon.ico') }}">

{{ dump(myObject) }}

Code separation

<!-- app/Ressources/views/base.html.twig -->
<!DOCTYPE html>
<html>
  <head>...</head>
  <body>
    {% block body %}{% endblock %}
  </body>
</html>

{# src/Conserto/Bundle/BeerBundle/Resources/views/Beer/index.html.twig #}
{% extends '::base.html.twig' %}
{% block body %}
{% if beer %}
    <p>Beer: {{ beer }}!</p>
{% endif %}
{% endblock %}

Entities

• Entity = Model (MVC)
• Looks like POJO: simple PHP class with attributes, constructor, getters and setters

# Generate entity with doctrine (also generate getters&setters):
$ php app/console generate:doctrine:entity

# Database creation/update
$ php app/console doctrine:schema:create
$ php app/console doctrine:schema:update

Doctrine

Doctrine annotations

/**
 * Beer
 *
 * @ORM\Table()
 * @ORM\Entity(repositoryClass="Conserto\BeerBundle\Entity\BeerRepository")
 */
class Beer
{
  /**
   * @var integer
   *
   * @ORM\Column(name="id", type="integer")
   * @ORM\Id
   * @ORM\GeneratedValue(strategy="AUTO")
   */
  private $id;

  /**
   * @var string
   *
   * @ORM\Column(name="name", type="string", length=255)
   */
  private $name;
  //...

Doctrine principle

$myBeer = new Beer();
$myBeer->setName('Kwak');
$myBeer->setAlcohol(8.4);

$anotherBeer = new Beer();
$anotherBeer->setName('Tripel Karmeliet');
$anotherBeer->setAlcohol(8.4);

//Step 1: Retrieve EntityManager service
$em = $this->getDoctrine()->getManager();

//Step 2: persist
$em->persist($myBeer);
$em->persist($anotherBeer);

//Step 3: Flush (generate&execute SQL)
$em->flush();

Doctrine: retrieve object

$em = $this->getDoctrine()->getManager();

$aBeer = $em->getRepository('ConsertoBeerBundle:Beer')->find($id);
$beers = $em->getRepository('ConsertoBeerBundle:Beer')->findAll();

$aBeer = $em->getRepository('ConsertoBeerBundle:Beer')->findOneByAbbey($abbey);
$beers = $em->getRepository('ConsertoBeerBundle:Beer')->findByAlcohol($alcohol);

Doctrine: update/delete

$em = $this->getDoctrine()->getManager();
//Update
$aBeer = $em->getRepository('ConsertoBeerBundle:Beer')->find(42);
aBeer->setAlcohol = 8.4;
$em->flush();

//Delete
$aBeer = $em->getRepository('ConsertoBeerBundle:Beer')->find(51);
$em->remove($beer);
$em->flush();

Doctrine: custom request

//src\Conserto\BeerBundle\Repository\BeerRepository.php
public function findByAbbeyAndAlcohol($abbey, $alcohol)
{
  $qb = $this->createQueryBuilder('b');

  $qb->where('b.abbey = :abbey')
     ->setParameter('abbey', $abbey)
     ->andWhere('b.alcohol < :alcohol')
     ->setParameter('alcohol', $alcohol)
     ->orderBy('b.name', 'DESC');

  return $qb
    ->getQuery()
    ->getResult()
  ;
}

Doctrine: relations

• One-to-one (1..1) ex: Beer--Image
• Many-to-one (n..1) ex: Abbey--Beer
• Many-to-many (n..n) ex: Beer--Distributor

Doctrine in Symfony2

Doctrine documentation

Form component

//src\Conserto\BeerBundle\Form\BeerType.php
public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('name')
        ->add('alcohol')
        ->add('desciption')
    ;
}

//src\Conserto\BeerBundle\Controller\BeerController.php
$beer     = $em->getRepository('ConsertoBeerBundle:Beer')->find($id);
$editForm = $this->createForm(BeerType::class, $beer, array(
    'action' => $this->generateUrl('conserto_beer_update'),
    'method' => 'PUT'
));

return $this->render('ConsertoBeerBundle:Beer:edit.html.twig', array(
    'beer'      => $beer,
    'edit_form' => $editForm->createView()
));

<!-- edit.html.twig -->
{{ form(edit_form) }} {# Will generate a HTML Form #}

Bootstrap form theme (since Symfony 2.6)

# app/config/config.yml
twig:
    form_themes:
        - 'bootstrap_3_layout.html.twig'

Remember: never trust user input!

Form validation

<?php
use Symfony\Component\Validator\Constraints as Assert;

class Beer
{
  //...

  /**
   * @var string
   *
   * @ORM\Column(name="name", type="string", length=255)
   * @Assert\NotBlank()
   * @Assert\Length(
   *  min = 2,
   *  minMessage = "Your Beer must be at least {{ limit }} characters long"
   * )
   */
  private $name;

Service Container

Use Dependency Injection pattern

# app/config/config.yml
services:
  my_mailer:
      class    : Conserto\HelloBundle\Mailer
      arguments: [sendmail]

class WhateverController extends Controller
{
  public function sendEmailAction()
  {
    // ...
    $mailer = $this->get('aMailer');
    $mailer->send('contact@beerapp.io', ...);
  }
}

Tips & tricks

Code generation

Crud generation (Controller, Form, Views, Routes)

$ php app/console generate:doctrine:crud

Reverse engineering (generate entities from database)

$ php app/console doctrine:mapping:import --force AcmeBlogBundle xml
$ php app/console doctrine:mapping:convert annotation ./src
$ php app/console doctrine:generate:entities AcmeBlogBundle

Useful commands

$ alias sf='php app/console'

Useful tools

• Grunt/Gulp: Task Runner (clear cache, assetics compilation...)
• Mailcatcher: catch mails
• Blackfire.io: Profiling Web Pages

Deployment

• Clear cache
• Check server configuration ($ php app/check.php)
• Use cache
• Verify your secret key (app/config/parameters.yml)
• Disable dev mode (app_dev.php)
• Customize errors pages
• Use cache !

Useful bundles

• FOSUserBundle
• FOSRestBundle
• DoctrineFixturesBundle
• StofDoctrineExtensionsBundle
• JMSSerializerBundle
• NelmioApiDocBundle
• LexikMaintenanceBundle

Coding standards

Please, stick the PSR (PHP Standard Recommendations)

Tools: PHP_CodeSniffer and PHP-CS-Fixer

.editorconfig file

# .editorconfig (editorconfig.org)
root = true
[*]
end_of_line = lf
charset = utf-8
trim_trailing_whitespace = true
insert_final_newline = true

[**.js]
indent_style = space
indent_size = 2

[**.php]
indent_style = space
indent_size = 4

Don't forget

• Refactor
• Refactor
• Refactor
• Refactor
• Refactor
• ...

About Symfony3

• Symfony2 code can run in Symfony3
• Checkout @deprecated annotation (in official doc)
• Upgrade from 2.8 to 3.0