Getting Started with

ZF2

About me

Matthew Weier O'Phinney

(@weierophinney)

PHP Developer since 2000

Zend Framework contributor since

January 2006; project lead since April

2009

Passionate open source advocate and

contributor

Getting Started

Zend Skeleton Application

A skeleton application using the new MVC layer and the

module system.

1 cd my/project/dir2 wget -O ZendSkeletonApplication.tgz ↲3 https://github.com/zendframework/ZendSkeletonApplication/↲4 tarball/master5 tar xzf ZendSkeletonApplication.tgz --strip-components=16 php composer.phar install

AND

Configure a web server, or use the PHP 5.4 built-in web

server:

1 cd public2 php -S localhost:8080

OR

Go to https://my.phpcloud.com/

Click the "New Application" button

Select "Empty Zend Framework 2.0 Application", and

then "Deploy Application"

Test it (and then connect via git or your IDE!)

I don't get it

What's next?

You probably want to know…

How to create a controller

How rendering works

How to create routes

We may get to that

But before I tell you about that stuff…

What is ZF2?

PHP >= 5.3.3

More flexibility

Event and service oriented

Install as much or as little as you want, how you want

More secure

Better defaults for SSL connections

Secure defaults for XML processing

Context-specific escaping mechanisms

A new core

The ZF1 way:

Singletons, Registries, Hard-Coded

and Soft Dependencies

The ZF2 way:

Event-Driven Services

Services

Why?

Decoupling.

Contract Oriented Design

Favor composition over inheritance

Encourage Dependency Injection, or, more

specifically Inversion of Control

Instead of this…

1 public function someAction() {2 $front = Zend_Controller_Front::getInstance();3 $bootstrap = $front->getParam('bootstrap');4 $db = $bootstrap->getResource('db');5 $service = new SomeService($db);6 $this->view->results = $service->doSomething();7 }

We do this…

1 public function setService(SomeService $service) {2 $this->service = $service;3 }45 public function someAction() {6 return array(7 'results' => $this->service->doSomething()8 );9 }

And inject when we retrieve the

controller:

1 function ($controllers) {2 $services = $controllers->getServiceLocator();3 $service = $services->get('SomeService');4 $controller = new SomeController();5 $controller->setService($service);6 return $controller;7 }

Isn't that more code?

It's code with benefits:

You can provide replacements easily.

Which means you can test more easily.

The code for construction happens in one, easily

located, easily reviewed place.

And you can do things like provide separate DB

connections for separate services more easily.

Zend\ServiceManager

ServiceManager

Very fast - no magic or discovery

Code — don't configure — your injections

Explicit wiring — it's just code — makes debugging

simpler

Explicit Services

Name => object instance

1 array('services' => array(2 'foo' => new Some\Component\Foo(),3 'bar' => $someObjectInstance,4 ));

Invokables

Name => instantiable class

1 array('invokables' => array(2 'foo' => 'Some\Component\Foo',3 ));

Factories

Name => callable return object

1 array('factories' => array( 2 'foo' => function ($services) { 3 return new Some\Component\Foo( 4 $services->get('bar') 5 ); 6 }, 7 'bar' => 'Some\Static::method', 8 'baz' => 'Some\Class\Implementing\FactoryInterface', 9 'bat' => 'Some\FunctorClass',10 ));

Aliases

Alias => some service or alias

1 array('aliases' => array(2 'my_foo' => 'foo', // alias a service3 'foo_master' => 'my_foo', // alias an alias4 ));

Abstract Factories

Factory that handles multiple services

1 array('abstract_factories' => array( 2 'Class\Implementing\AbstractFactoryInterface', 3 $someAbstractFactoryInstance, 4 ); 5 6 class SampleAbstractFactory implements AbstractFactoryInterface 7 { 8 public function canCreateServiceWithName( 9 ServiceLocatorInterface $services, $name, $requestedName10 ) {/* */ }11 public function createServiceWithName(/* same signature */)12 { /* */ }13 }

(Un)Shared Service

Shared by default; choose not to if you want.

1 array('shared' => array(2 'EventManager' => false, // default is true3 ));

Initializers

Perform operations on new instances.

1 array('initializers' => array(2 function ($instance, $services) {3 if ($instance instanceof EventManagerAwareInterface) {4 $instance->setEventManager(5 $services->get('EventManager')6 );7 }8 },9 ));

Plugin Managers

What?

A specialized form of ServiceManager

Allows retrieving context-specific objects, using short

names

Typically managed by the application ServiceManager

E.g.: view helpers, controllers, controller plugins, etc.

What you need to know…

Configuration is exactly the same as for the

ServiceManager

The ServiceManager is composed in, and retrievable via

getServiceLocator() in factories

Example:

1 'factories' => array(2 // $helpers is the View Helper plugin manager instance3 'something' => function ($helpers) {4 $services = $helpers->getServiceLocator();5 $model = $services->get('SomeModel');6 $helper = new SomethingHelper($model);7 return $helper;8 },9 )

EventManager

EventManager in a Slide

Trigger events

Listen and react to triggered events

Example

1 $events = new EventManager(); 2 $events->attach('do', function ($e) { 3 $event = $e->getName(); 4 $params = $e->getParams(); 5 printf( 6 'Handled event "%s" with parameters "%s"', 7 $event, 8 json_encode($params) 9 );10 });11 $params = array('foo' => 'bar', 'baz' => 'bat');12 $events->trigger('do', null, $params);

Terminology

An Event is a message encapsulating information.

An Event Manager is an object that aggregates listeners

for one or more named events, and which triggers

events.

A Listener is a callback that can react to an event.

Shared Event Listeners

Use cases:

Often you want to attach to objects not yet created

Often you want to attach to a group of objects

Shared Event Manager

EventManager instances are not shared.

All EventManager instances pulled from the

ServiceManager are injected with a shared

SharedEventManager instance

Retrieve that from the ServiceManager, or an

EventManager instance

API is same, except that you provide a "context" or

"identifier" as a preliminary argument to attach()

Shared Event Manager Usage

1 $shared = $events->getSharedManager();2 $shared = $services->get('SharedEventManager');34 $shared->attach('Zend\Stdlib\DispatchableInterface', 'dispatch',5 $callback, $priority);

Topics not covered:

Listener priority (high, positive integers run first;

negative integers run last)

Aggregates (one object, many listeners, attach once)

Short-circuiting (stop execution within a listener, or

based on the result of a listener)

Wildcard events and identifiers when attaching listeners

Recap

We learned all about Services, and how the

ServiceManager manages them.

We learned about Events, the EventManager, and

shared events.

MVC

Event driven architecture

Everything is an event

Services

Uses ServiceManager to wire default workflow and

event listeners

Developers provide additional services and service

configuration

Controllers are services!

Modules

“A module provides services for the MVC, and wires

event listeners.”

Modules for ZF2

Should do one thing, and do it well.

Modules are "Plug and play" technology

Modules are simply:

A namespace

Containing a single classfile: Module.php

Let's create a module

A little boilerplate:

1 mkdir -p module/MyMarkdown2 touch module/MyMarkdown/Module.php

Edit our new Module classfile:

1 namespace MyMarkdown; 2 3 use Zend\View\Helper\AbstractHelper; 4 5 class Module extends AbstractHelper 6 { 7 public function getViewHelperConfig() { 8 return array('services' => array('markdown' => $this)); 9 }1011 public function __invoke($string = null) {12 require_once 'php-markdown/markdown.php';13 return Markdown($string);14 }15 }

Add it to the application:

1 // in config/application.config.php2 return array(3 'modules' => array(4 'Application',5 'MyMarkdown', // add this!6 ),7 /* ... */8 );

Usage:

1 <?php // in a view script: ?>2 <?= $this->markdown($this->someMarkdowntext) ?>

Actually, that one exists already

https://github.com/EvanDotPro/EdpMarkdown

1 git submodule add↲2 https://github.com/EvanDotPro/EdpMarkdown ↲3 vendor/EdpMarkdown

Add EdpMarkdown to your

config/application.config.php, and you're done.

What about

controllers?

Controllers are services

Controllers are boring

IndexController.php

1 namespace Application\Controller; 2 3 use Zend\Mvc\Controller\AbstractActionController; 4 use Zend\View\Model\ViewModel; 5 6 class IndexController extends AbstractActionController 7 { 8 public function indexAction() 9 {10 return new ViewModel();11 }12 }

The key points are:

Know how to configure services

Know how to wire event listeners

Remember that controllers are services, and now return

information

Modules inform the MVC of services (controllers!) and

wire events.

Resources

The user guide: http://bit.ly/zf2userguide

Download info: http://bit.ly/zf2downloads

Participate! http://bit.ly/zf2giveback

Thank You

Feedback?

@weierophinney on twitter

#zftalk.dev on Freenode IRC

http://framework.zend.com/