PHP 5.4 What’s New and What’s Changed

APRIL 7, 2012

michael stowe

• 10+ years experience hacking PHP

• Developed web applications for large non-profits, the medical field, law

enforcement, and ecommerce websites

• Open Source Contributor (3 WordPress plugins, multiple scripts)

• Software Engineer at CaringBridge.org (half a million visitors every day)

• Zend Certified PHP 5.3 Software Engineer

.com

@mikegstowe

MIKESTOWE

THE MOST IMPORTANT CHANGE

The 3 in 5.3 became a 4! (very important)

BUT WHAT WILL PHP 5.4 BREAK?

Well for starters…

• break and continue no longer accept variable arguments • safe_mode is no longer supported • Salsa10/20 algorithms have been removed • Magic Quotes • (object) null now throws a warning • (string) array() now throws an E_NOTICE • Shadowing SuperGlobals as parameter names now causes fatal error

Reserved Keywords In PHP 5.4, the following keywords are now reserved and cannot be used as function or class names:

• trait

• callable

• insteadof

Bye-Bye Functions In PHP 5.4, the following functions have been removed: • define_syslog_variables

• import_request_variables

• session_is_registered

• session_register

• session_unregister

• mysqli_bind_param

• mysqli_bind_result

• mysqli_fetch

Bye-Bye Extensions In PHP 5.4, the following extension has been removed:

• sqlite

Changed Extensions Other important changes:

• mysqli_result() now implements Traversable

• pdo_mysql no longer supports MySQL < 4.1

• mysqlnd has had named pipes support added

INI Removals Other important changes:

• register_globals and register_long_arrays have been removed!!! • safe_mode and all related components removed • y2k_compliance removed • Zend.ze1_compatibility_mode removed

(it’s about time!)

NOW FOR THE JUICY STUFF

PHP 5.4 INI STUFF PHP 5.4 comes with the following new ini directives:

• cli.pager and cli.prompt for CLI SAPI using readline in interactive mode • zend.multibyte to control new multibyte support (off by default) • session.upload directives • enable_post_data_reading to stop POST data from being read and processed (when disabled) • default_charset is now UTF-8 in distributed php ini files (still defaults to “”).

New Functions Here are some of the brand new functions!

• hex2bin()

• http_response_code()

• get_declared_traits()

• getimagesizefromstring()

• stream_set_chunk_size()

• socket_import_stream()

• trait_exists()

• header_register_callback()

• class_uses()

• session_status()

• session_register_shutdown()

• mysqli_error_list()

• mysqli_stmt_error_list() • and others (Libxml, LDAP, Intl)

New Functions (cont) Here are some of the brand new functions!

New Features in 5.4 And the big ticket items in PHP 5.4 include:

• Binary Notation • Short-hand arrays • Dereferencing arrays • Traits • Class Instantiation Chaining • Session Status and Handler • File Upload Tracking • Built in Web Server

BINARY NOTATION Previously in PHP, you were able to write integers as decimals (10), Octals (012), and Hexadecimals (0xA). Now in PHP 5.4 you can use binary notation for integers by preceding the binary number with “0b” – such as (0b1010).

That‟s zero-lower-case-b followed by the binary.

<?php

// Decimal

echo (string) 10; // 10

// Octal

echo (string) 012; // 10

// Hexadecimal

echo (string) 0xA; // 10

// Binary

echo (string) 0b1010; // 10

?>

Example Usage

That‟s zero-lower-case-b followed by the binary.

Binary is calculated by using the powers of 2.

IE 20, 21, 22, 23, etc.

So 100101 would be equal to: [(1) × 25] + [(0) × 24] + [(0) × 23] + [(1) × 22] + [(0) × 21] +

[(1) × 20]

SHORT-HAND ARRAYS Finally, in PHP you can now use the short bracket syntax for arrays. While really not a huge deal, this aligns PHP with many of the other programming languages, and will probably make switching from another language just a little easier (although array(1,2,3) is pretty simple).

$array = array(1,2,3); $array = [1,2,3];

<?php

$oldArray = array(1,2,3);

echo (string) $oldArray[1]; // 2

$newArray = [1,2,3];

echo (string) $newArray[1]; // 2

$newArray = [1 => 'Apple', 2, 3];

echo (string) $newArray[1]; // Apple

$newArray = ['apple' => 'Orange'];

echo $newArray['apple']; // Orange

?>

Example Usage

You can have values OR key => value pairs!

$array = array(1,2,3); $array = [1,2,3];

DEREFERENCING ARRAYS Another nice feature in regards to arrays is Array Dereferencing, or being able to access an array object directly off of a method or function.

echo functionReturningAnArray()[1];

<?php

function getArray()

{

return array(1,2,3);

// or return [1,2,3]; short syntax ;)

}

// PHP 5.3

echo (string) getArray()[1]; // error

// PHP 5.4

echo (string) getArray()[1]; // 2

?>

Example Usage

echo functionReturningAnArray()[1];

This works for functions and methods

TRAITS The addition of traits provides the flexibility of “extending” multiple classes without having to go through an entire chain (allowing horizontal design). Unlike many languages, PHP Traits can also contain properties, however, if the class contains a property with the same name it will throw an E_STRICT warning IF the class property === the trait property, or a fatal error if the class property !== the trait property.

Traits are interchangeable classes that can be imported into a class through the “use” declaration.

<?php

trait MyTrait

{

public $MyProperty = 'hello';

public function MyMethod()

{

echo 'world';

}

}

class MyClass

{

use MyTrait;

public function DoStuff()

{

echo $this->MyProperty;

echo ' ';

$this->MyMethod();

}

}

(new MyClass())->DoStuff(); // echos out 'hello world'

?>

Example Usage

<?php

class MyClass

{

use MyTrait, YourTrait

// Assuming both traits have

// exampleMethod() this will

// cause a conflict, unless we

// tell it not to...

{

// Alias for MyTrait's method

MyTrait::exampleMethod as example1;

// Use YourTrait instead of MyTrait

YourTrait::exampleMethod insteadof MyTrait;

}

}

$myClass = new MyClass();

// MyTrait::exampleMethod

$myClass->example1();

// YourTrait::exampleMethod

$myClass->exampleMethod();

?>

Using Multiple Traits

To avoid method conflicts, you can create aliases

using as AND tell PHP which trait‟s method to use

insteadof another trait‟s identically named method

We have to use insteadof to

avoid a conflict

as allows us to still access MyTrait’s exampleMethod

<?php

trait MyTrait

{

public function MyMethod()

{

echo 'MyTrait';

}

}

class MyClass

{

use MyTrait;

public function MyMethod()

{

echo 'MyClass';

}

public function DoStuff()

{

$this->MyMethod();

}

}

(new MyClass())->DoStuff(); // echos out 'MyClass'

?>

Class Overrides

We can still access MyTrait::MyMethod by creating an alias

as shown in the last slide

Trait Functions

For more on traits visit: http://php.net/manual/en/language.oop5.traits.php

trait_exists() – similar to class_exists(), this function checks to see if the trait has been defined and returns an boolean. get_declared_traits() – similar to get_declared_classes(), this function returns an array of traits that have been declared.

Traits & the Reflection Class

For more on the ReflectionClass visit: http://php.net/manual/en/class.reflectionclass.php

There have also been several methods added to the ReflectionClass: getTraits() returns an array of all traits used in a class, while getTraitNames() returns an array of the trait names in a class. getTraitAliases() returns an array of aliases linked to its original trait and method. isTrait() returns whether or not a tested object is a trait

CLASS INSTANTIATION CHAINING

As you may have noticed by the Traits code example, PHP 5.4 let’s you chain a class instantiation using parenthesis. This allows you to instantiate a class, and call a method all in one act.

(new ClassName())->classMethod(„param1‟);

<?php

class Test

{

public function hello()

{

echo 'hello world';

}

}

// in PHP 5.3 this would be an error

// in PHP 5.4 it echos 'hello world'

echo (new Test())->hello();

?>

Example Usage

Keep in mind that just because you can do something doesn’t mean you should. Stick to coding standards.

(new ClassName())->classMethod(„param1‟);

SESSIONS

PHP 5.4 introduces four new Session items; session_status(), session_register_shutdown(), SessionHandler, and Session based file upload tracking.

SESSION_STATUS

session_status() returns the CURRENT status of the session, whether sessions are disabled, if there is an active session, or if there are no active sessions.

session_status() allows you to see the session‟s

status in real time instead of checking the SuperGlobal and headers.

Let’s take a look at it in action…

<?php

//If sessions are disabled

//would return PHP_SESSION_DISABLED (0)

echo session_status(); // echos PHP_SESSION_NONE (1)

session_start();

echo session_status(); // echos PHP_SESSION_ACTIVE (2)

session_destroy();

echo session_status(); // echos PHP_SESSION_NONE (1)

?>

Example Usage

session_status() allows you to see the session‟s status in

real time instead of checking the SuperGlobal and headers.

SESSION_REGISTER_SHUTDOWN

session_register_shutdown() registers session_write_close() as a shutdown function.

It‟s important to remember that all the other session_register functions have been deprecated.

<?php

session_start();

session_register_shutdown();

?>

SESSIONHANDLER SessionHandler is a class introduced in PHP 5.4 to help make building custom session handlers easier. The SessionHandler class implements the SessionHandlerInterface, which may be independently called in by a custom class.

An instance of this class, a class that extends it, or a

custom class implementing the SessionHandlerInterface

will be passed to session_set_save_handler()

SessionHandler methods include: • close() – executed on the close of the session • destroy() – executed when destroying a session • gc() – cleans up expired sessions • open() – when opening or creating a session • read() – executed after session_start()

• write() – executed by session_write_close()

SESSIONHANDLER

An instance of this class, a class that extends it, or a

custom class implementing the SessionHandlerInterface

will be passed to session_set_save_handler()

<?php

class MyHandler extends SessionHandler

{

public function read($session_id)

{

/** GET SESSION DATA FROM YOUR SOURCE **/

}

public function write($session_id, $session_data)

{

/** WRITE SESSION DATA TO YOUR SOURCE **/

}

}

?>

Example Usage

http://www.php.net/manual/en/class.sessionhandler.php

An instance of this class, a class that extends it, or a

custom class implementing the SessionHandlerInterface

will be passed to session_set_save_handler()

FILE UPLOAD TRACKING File upload tracking allows you to track the progress of a file upload through sessions.

This is done only using PHP and

JavaScript!

File upload tracking is setup through the session.upload_progress ini directives, and then stored in the $_SESSION SuperGlobal

File Upload Tracking INI Directives: • session.upload_progress.enabled

• session.upload_progress.cleanup

• session.upload_progress.prefix

• session.upload_progress.name

• session.upload_progress.freq

• session.upload_progress.min_freq

FILE UPLOAD TRACKING

File upload tracking is setup through the session.upload_progress ini directives, and then stored in the $_SESSION SuperGlobal

FILE UPLOAD TRACKING After setting the appropriate ini directives, you will need to setup your upload form:

<form action="<?php echo $_SERVER["PHP_SELF"]; ?>"

method="POST" id="myForm"

enctype="multipart/form-data">

<input type="hidden" value="myForm"

name="<?php echo ini_get("session.upload_progress.name"); ?>">

<input type="file" name="userfile"><br>

<input type="submit" value="Start Upload">

</form>

You can then access the file upload progress data from the session:

<?php

session_start();

$key = ini_get("session.upload_progress.prefix") . "myForm";

if (!empty($_SESSION[$key])) {

$current = $_SESSION[$key]["bytes_processed"];

$total = $_SESSION[$key]["content_length"];

echo $current < $total ? ceil($current / $total * 100) : 100;

}

else {

echo 100; // File has been Completely Uploaded

}

?>

FILE UPLOAD TRACKING

With the previous PHP script we can return the upload progress in a percentage back to the original form via ajax.

Mix in a little CSS to make it look even

better!

See more code and learn how to make the above example at PHP Master: http://phpmaster.com/tracking-upload-progress-with-php-and-javascript/

FILE UPLOAD TRACKING

$ cd ~/public_html

$ php -S localhost:8000

BUILT-IN WEBSERVER PHP 5.4 also comes with a built-in webserver via the command line for convenience

The server is activated using the –S option

Note: the webserver is for development purposes only, and should not be used in production

PHP 5.4.0 Development Server started at Thu Jul 21 10:53:19 2011

Listening on localhost:8000

Document root is /home/me/public_html

Press Ctrl-C to quit.

[Thu Jul 21 10:53:45 2011] ::1:55801 GET /mylogo.jpg - Request read

[Thu Jul 21 10:53:52 2011] ::1:55803 GET /abc.html - Request read

[Thu Jul 21 10:53:52 2011] ::1:55804 GET /favicon.ico - Request read

$ cd ~/public_html

$ php -S localhost:8000 router.php

Example Usage

Note: the webserver is for development purposes only, and should not be used in production

Would return something like

AND I ALMOST FORGOT…

FASTER!

PHP Performance

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Want to see something really cool?

3.1.2012 RELEASED

http://php.net/ChangeLog-5.php

To read that tiny text and see all the changes

@mikegstowe