Migrating to PHP 5.3
Stefan Priebsch
July 31st 2009
Copyright © 2009 thePHP.cc, Germany

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Sebastian Arne Stefan
Bergmann Blankerts Priebsch

Why PHP 5.3?
 Faster
 Better tested
 Officially supported on all Windows platforms
 Loads of new features

Selected PHP 5.3 Highlights
 Namespaces
 Late Static Binding
 New extensions: fileinfo, intl, Phar
 New datastructures in SPL
 SQLite3
 mysqlnd
 Garbage Collection

Namespaces
 Work for classes, functions and constants
 Namespace separator:
 Work like directory navigation
 Relative Path
namespace foobar + class baz = foobarbaz
namespace foo + class barbaz = foobarbaz
 Absolute Path
namespace foobar + class baz = baz
 Prepend built-in classes and functions with
 throw new Exception
 strlen(...)

Namespaces Example
namespace myApplicationModels;
use FrameworkModelModelBase as Model;
class UserModel extends Model
{
...
}

Late Static Binding Example
class BaseClass
{
static protected $foo = 'foo';
static public function getFoo()
{
return self::$foo;
}
}
var_dump(BaseClass::getFoo());
Will output: string(3) "foo"

Late Static Binding Example
class SubClass extends BaseClass
{
static protected $foo = 'bar';
}
var_dump(SubClass::getFoo());
Will output: string(3) "foo"

Late Static Binding Example
class BaseClass
{
static protected $foo = 'foo';
static public function getFoo()
{
return static::$foo;
}
}
var_dump(SubClass::getFoo());
Will output: string(3) "bar"

Late Static Binding Example
class SomeClass
{
static public function foo()
{
var_dump('foo method');
}
}
$classname = 'SomeClass';
$classname::foo();
Will output: string(10) "foo method"

Phar
 PHP Archive
 Stream wrapper-based
PHP extension + Userland implementation
 Can be executable
 No temporary files involved
 php.ini: phar.readonly=Off;
You cannot set this at runtime!

Phar Example
src/:
... any files ...
stub.php:
Phar::mapPhar('alias.phar');
...
__HALT_COMPILER();
create_phar.php:
$phar = new Phar('executable.phar');
$phar->buildFromDirectory('./src');
$phar->setStub(
file_get_contents('./stub.php'));

Migration Problems
 Environment
 Old Extensions
 Compile-time errors
 Name Conflicts
 More strictness
 Runtime errors
 New error messages (E_DEPRECATED)
 Logic errors
 Altered behaviour

Altered function behaviour
$haystack = 'hello world';
$needle = 'lo';
var_dump(strrpos($haystack, $needle));

Altered function behaviour
$haystack = 'hello world';
$needle = 'lo';
var_dump(strrpos($haystack, $needle));
PHP 4: int(9)

Altered function behaviour
$haystack = 'hello world';
$needle = 'lo';
var_dump(strrpos($haystack, $needle));
PHP 4: int(9)
PHP 5: int(3)

Solution: Create a wrapper
function strrpos_wrapper($haystack,
$needle,
$offset = 0)
{
return strrpos($haystack,
substr($needle, 0, 1),
$offset);
}

More Strictness
abstract class Test
{
abstract static function foo();
}
Strict standards:
Static function should not be abstract

More Strictness
abstract class Test
{
abstract private function foo();
}
Fatal error:
Abstract function cannot be declared private

Useful Tools
 Lint: php -l
 Validators (HTML, XML, CSS, JS)
 PHPUnit
 http://www.phpunit.de
 Selenium
 http://seleniumhq.org
 xdebug
 http://www.xdebug.org

xdebug Function Trace

Mocking
include_once './library/function.php';
for($i = 0; $i < 5; $i++) {
var_dump(get_random_value());
}
library/function.php:
function get_random_value()
{
return rand(1, 10);
}

Mocking
mock_library/function.php:
function get_random_value()
{
static $i = 0;
static $random_values =
array(1, 2, 3, 4, 5);
return $random_values[$i++];
}

Mocking
include_once './mock_library/function.php';
for($i = 0; $i < 5; $i++) {
var_dump(get_random_value());
}

How To Migrate
 Fix errors/warnings/notices
 Normalize the PHP configuration
 Set up two test systems, old and new
 Do A/B testing
 Compare the results
 Fix the problems
 Switch the production system

Future­Proof PHP Configuration
 ze1.compatibility_mode=Off
 allow_call_time_pass_reference=Off
 register_globals=Off
 magic_quotes_*=Off
 register_long_arrays=Off

http://www.phparch.com/books/index

Code Works '09 Workshops
 ”Advanced OOP and Design Patterns”
 ”PHP Code Review” with Arne Blankerts
and Sebastian Bergmann
http://cw.mtacon.com

Thank You.
■ http://thePHP.cc
■ http://www.priebsch.de
■ http://www.slideshare.net/spriebsch
■ http://twitter.com/spriebsch
■ stefan@thePHP.cc, IRC: spriebsch
Copyright © 2009 thePHP.cc, Germany