PHP Wrap-up

Marcus Börger

Mexico CONSOL 2007

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WelcomeSome statistics

Revisiting PHP 4

Looking at PHP 5.0, 5.1

Upgrading to new PHP 5.2

A glimpse at the future PHP 6

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PHP usage by IP

Other35%

PHP65%

Nexen Services http://www.nexen.net © 2005 -2007

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27 Dec 2002: PHP 4.3Do not use

InsecureUnsupportedNo longer continued

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11 Jul 2005: PHP 4.4Fixes a memory corruption with referencesOnly security fixesNo new features at allAvailable for quite some timePHP 4.4.5 released 14th February 2007

No PHP 4.5 will come out

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PHP 4 and OOP ?Poor Object model

MethodsNo visibilityNo abstracts, No finalStatic without declaration

PropertiesNo static propertiesNo constants

InheritanceNo abstract, final inheritance, no interfacesNo prototype checking, no types

Object handlingCopied by valueNo destructors

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13 Jul 2004: PHP 5.0Completely rewritten Zend Engine 2.0First version with the new object modelLibxml2 based XML replaces SablotronNew extensions

DOM, MySQLi, PDO, SimpleXML, SPL

Unbundled mysql client library

Sometimes called the "alpha" versionDiscontinued

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Objects referenced by ID

Objects are no longer somewhat special arraysObjects are no longer copied by defaultObjects may be copied using clone/__clone()

class Object {};

$obj = new Object();

$ref = $obj;

$dup = clone $obj; Class Object

$obj $ref $dup

Instance 1 Instance 2

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ZE2's revamped object modelObjects are referenced by identifiersConstructors and DestructorsStatic membersDefault property valuesConstantsVisibilityInterfacesFinal and abstract membersInterceptorsExceptionsReflection APIIterators

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Revamped Object ModelPHP 5 has really good OOP support

Better code reuseBetter for team developmentEasier to refactorSome patterns lead to much more efficient codeFits better in marketing scenarios

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From engine overloading . . .Zend engine 2.0+ allows to overload the following

by implementing interfacesForeach by implementing Iterator, IteratorAggregateArray access by implementing ArrayAccessSerializing by implementing Serializable

by providing magic functionsFunction invocation by method __call()Property access by methods __get() and __set()Automatic loading of classes by function __autoload()

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. . . to SPL

It is easy in a complex way- Lukas Smith

php conference 2004

A collection of standard interfaces and classesMost of which based around engine overloading

A few helper functions

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What is SPL about & what forCaptures some common patterns

Advanced Iterators

Functional programming

File and directory handling

Makes __autoload() useable

Exception hierarchy with documented semantics

Captures some common patterns

Advanced Iterators

Functional programming

File and directory handling

Makes __autoload() useable

Exception hierarchy with documented semantics

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ExceptionsRespect these rules

1. Exceptions are exceptions2. Never use exceptions for control flow3. Never ever use exceptions for parameter passing

<?phptry {

// your codethrow new Exception();

}catch (Exception $e) {

// exception handling}?>

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Practical use of exceptionsConstructor failure

Converting errors/warnings to exceptions

Simplify error handling

Provide additional error information by tagging

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Constructor failureIn PHP 4.4 you would simply unset($this)Provide a param that receives the error condition

<?phpclass Object{

function __construct( & $failure){

$failure = true;}

}$error = false;$o = new Object($error);if (!$error) {

// error handling, NOTE: the object was constructedunset($o);

}?>

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Constructor failureIn 5 constructors do not return the created objectExceptions allow to handle failed constructors

<?phpclass Object{

function __construct(){

throw new Exception;}

}try {

$o = new Object;}catch (Exception $e) {

echo "Object could not be instantiated\n";}?>

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Simplify error handlingTypical database access code contains lots of if's

<html><body><?php$ok = false;$db = new PDO('CONNECTION');if ($db) {

$res = $db->query('SELECT data');if ($res) {

$res2 = $db->query('SELECT other');if ($res2) {

// handle data$ok = true; // only if all went ok

}}

}if ($ok) echo '<h1>Service currently unabvailable</h1>';?></body></html>

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Simplify error handlingTrade code simplicity with a new complexity

<html><body><?phptry {

$db = new PDO('CONNECTION');$db->setAttribute(PDO::ATTR_ERRMODE,

PDO::ERRMODE_EXCEPTION);$res = $db->query('SELECT data');$res2 = $db->query('SELECT other');// handle data

}catch (Exception $e) {

echo '<h1>Service currently unabvailable</h1>';error_log($e->getMessage());

}?></body></html>

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What are IteratorsIterators are a concept to iterate anything that contains other things.

Iterators allow to encapsulate algorithms

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What are IteratorsIterators are a concept to iterate anything that contains other things. Examples:

Values and Keys in an array ArrayObject, ArrayIteratorText lines in a file SplFileObject

Files in a directory [Recursive]DirectoryIteratorXML Elements or Attributes ext: SimpleXML, DOMDatabase query results ext: PDO, SQLite, MySQLiDates in a calendar range PECL/date (?)Bits in an image ?

Iterators allow to encapsulate algorithms

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What are IteratorsIterators are a concept to iterate anything that contains other things. Examples:

Values and Keys in an array ArrayObject, ArrayIteratorText lines in a file SplFileObject

Files in a directory [Recursive]DirectoryIteratorXML Elements or Attributes ext: SimpleXML, DOMDatabase query results ext: PDO, SQLite, MySQLiDates in a calendar range PECL/date (?)Bits in an image ?

Iterators allow to encapsulate algorithmsClasses and Interfaces provided by SPL:AppendIterator, CachingIterator, LimitIterator, FilterIterator, EmptyIterator, InfiniteIterator, NoRewindIterator, OuterIterator, ParentIterator, RecursiveIterator, RecursiveIteratorIterator, SeekableIterator, SplFileObject, . . .

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Array vs. IteratorAn array in PHP $ar = array()

can be rewound: reset($ar)

is valid unless it's key is NULL: !is_null(key($ar))

have current values: current($ar)

have keys: key($ar)

can be forwarded: next($ar)

Something that is traversable $it = new Iterator;

may know how to be rewound: $it->rewind()(does not return the element)

should know if there is a value: $it->valid()

may have a current value: $it->current()

may have a key: $it->key()(may return NULL at any time)

can forward to its next element: $it->next()

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24 Nov 2005: PHP 5.1New extension XMLReaderAdded new date/time handlingAdd streams filters bz2 and zlibImproved interactive mode php –aMajor changes/improvements to MySQLi and SPLSince 5.1.6 var is an alias for public

Sometimes called 'beta' versionDiscontinued

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02 Nov 2006: PHP 5.2Current stable version5.2.1 released on 9th February5.2.2+ only small feature changes and additionsImproved the Zend Memory ManagerOver 300 fixes between 5.1.6 and 5.2.1

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PHP 5.2: New extensionsFilter Input filtering/validation

Date Date handling functions and objects

JSON JavaScript Object Notation

XMLWriter Counterpart to XMLReader

ZIP Full read & write ZIP support

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PHP 5.2: New featuresNow __tostring() works as expected everywhereNew error severity E_RECOVERABLE_ERRORAdded/improved SPL features

RegexIteratorSplFileObject with CSV read supportCachingIterator now allows caching

RFC 2397 (data: stream) supportAdded forward support for 'b' prefix to stringsLots of minor additions/improvements

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PHP 5.2: PerformanceNew Memory Manager + Heap ProtectionFaster include/require_onceOptimized str_replace() and implode() functionsFaster try {} catch {} blocksSignificantly faster performance on Win32Optimized shutdown sequenceMany other optimizations

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PHP 5.2: SecurityNew configuration option allow_url_includeOver 40 security fixesMore accurate memory usage trackingFilter extension can help filter out hostile input

XSSSQL Injection

Memory limit is always enabled.

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PHP 5.2: ChangesRespect new E_RECOVERABLE_ERROR in E_ALLNo more 'abstract static' methods in classesWhen using external resources, allow_url_includeFinally activated classes DateTime, DateTimeZoneInheritance rules check for return by reference

Detailed instructions in README.UPDATE_5_2

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PHP 5.3Scheduled for end of 2007New features that cannot be done in 5.2

In discussion:Bundling APC or another compiler cacheNamespacesAdding operator ifsetor or ?:

$a = ifsetor($input, $default);

$a = $input ?: $default;

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PHP 6Integrated native Unicode support leveraging ICUExtensions iconv and mbstring get deprecated

Native Unicode string type using UTF-16Additional binary string typeBackwards compatibleControlled via INI --unicode-semantics={on|off}New escape sequences \uXXXX and \UXXXXXXXX

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--unicode.semantics=offOld behavior where 1 character means 1 byte

$str = "Hello, world"; // ASCII encodingecho strlen($str); // result is 12

$jp = "検索オプション"; // UTF-8 encodingecho strlen($jp); // result is 21

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--unicode.semantics=onStrings are unicode type; 1 character >= 1 byte

$str = "Hello, world"; // Unicode stringecho strlen($str); // result is 12

$jp = "検索オプション"; // Unicode stringecho strlen($jp); // result is 7

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Wait, I like binaryThe prefix b denotes binary literals

$str = b"Hello, world"; // Binary stringecho strlen($str); // result is 12

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At Last some HintsList of all SPL classes PHP 5.0.0

php –r 'print_r(array_keys(spl_classes()));'

Reflection of a built-in class PHP 5.1.2php --rc <Class>

Reflection of a function or method PHP 5.1.2php --rf <Function>

Reflection of a loaded extension PHP 5.1.2php --re <Extension>

Extension information/configuration PHP 5.2.2php --ri <Extension>

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THANK YOUThis Presentation

http://somabo.de/talks/PHP

http://php.netUpgrading to 5.2

README.UPDATE_5_2SPL Documentation

http://php.net/~hellyPhar

http://pecl.php.net/packages/pharhttp://php.net/phar