phpAspect A spect- O riented P rogramming William Candillon { [email_address] }

O verview Acknowledgment Introduction to AOP phpAspect New features Conclusion

Acknowledgment

Introduction to AOP

phpAspect

New features

Conclusion

A cknowledgment Gilles Vanwormhoudt ( [email_address] ) PhD in computer science at Telecom Lille Collaborator on the phpAspect project Yijun Yu ( [email_address] ) PhD in computer science, University of Toronto Author of Yaxx Sebastian Bergmann ( [email_address] ) Diploma Thesis, University of Bonn. Google soc mentor

Gilles Vanwormhoudt ( [email_address] )

PhD in computer science at Telecom Lille

Collaborator on the phpAspect project

Yijun Yu ( [email_address] )

PhD in computer science, University of Toronto

Author of Yaxx

Sebastian Bergmann ( [email_address] )

Diploma Thesis, University of Bonn.

Google soc mentor

P rogramming evolution

Introduction to AOP

O bject- O riented P rogramming Advantages Business modeling Reusable technicals components Design patterns Frameworks Vertical organization Inheritance and interfaces Objects graph

Advantages

Business modeling

Reusable technicals components

Design patterns

Frameworks

Vertical organization

Inheritance and interfaces

Objects graph

T echnicals aspects in OOP

S ymptoms Inheritance can't modularize horizontal concerns Code Tangling Code scattering Difficulties Code comprehension Code reusability Code evolution

Inheritance can't modularize horizontal concerns

Code Tangling

Code scattering

Difficulties

Code comprehension

Code reusability

Code evolution

A spect- O riented P rogramming A new programming paradigm... Working with OOP Split technicals concerns from the business logic ...defining mechanisms for Writing aspects as a new software entity Wrapping crosscutting concerns Coating business logic with technicals concerns

A new programming paradigm...

Working with OOP

Split technicals concerns from the business logic

...defining mechanisms for

Writing aspects as a new software entity

Wrapping crosscutting concerns

Coating business logic with technicals concerns

G eneral idea Inversion of technicals dependencies

Inversion of technicals dependencies

J oinpoints Identified instructions in the program flow: Method execution (1) Attribute writing/reading (2) Objects construction (3) Method call (4) Objects destruction (5) Exception throwing (6) A pointcut is a logical association of joinpoints 1 2 3 4 5 6

Identified instructions in the program flow:

Method execution (1)

Attribute writing/reading (2)

Objects construction (3)

Method call (4)

Objects destruction (5)

Exception throwing (6)

A pointcut is a logical association of joinpoints

C ode advices Injected code in pointcuts 3 types: Before Around After Aspect and joinpoint reflection to explore the context Methods, arguments, targeted object etc...

Injected code in pointcuts

3 types:

Before

Around

After

Aspect and joinpoint reflection to explore the context

Methods, arguments, targeted object etc...

I nter-type declarations Inter-type attributes Inter-type constants Inter-type methods

Inter-type attributes

Inter-type constants

Inter-type methods

W ildcards and operators * denotes any method visibility, method scope, class name, method name or parameters number. + denotes type or any subclass or subinterface of a given type in a join point . The || offers the possibility to combine join points in an advice declaration.

* denotes any method visibility, method scope, class name, method name or parameters number.

+ denotes type or any subclass or subinterface of a given type in a join point .

The || offers the possibility to combine join points in an advice declaration.

S imple persistence example Business logic Aspect

Business logic

Aspect

phpAspect

PHP A highly dynamic language... Easy to learn Object-Oriented Mainly designed for web applications Used in more than 25 millions of websites. ...more and more used outside its web context Rapid prototyping PHP-GTK applications Command-Line interpreter

A highly dynamic language...

Easy to learn

Object-Oriented

Mainly designed for web applications

Used in more than 25 millions of websites.

...more and more used outside its web context

Rapid prototyping

PHP-GTK applications

Command-Line interpreter

S tate of the art in PHP phpAspect Static approach Compiler architecture (Lex/Yacc) Seasar Dynamic approach Using PHP containers GAP, by Sebastian Bergmann Only conceptual for now Other projects: AOPHP, aspectPHP, AOP Library for PHP etc...

phpAspect

Static approach

Compiler architecture (Lex/Yacc)

Seasar

Dynamic approach

Using PHP containers

GAP, by Sebastian Bergmann

Only conceptual for now

Other projects: AOPHP, aspectPHP, AOP Library for PHP etc...

A virtual cart A client add products in the cart. Business logic without any technicals concerns.

A client add products in the cart.

Business logic without any technicals concerns.

A logging aspect Log every added articles and give status of the order After weaving Result

Log every added articles and give status of the order

After weaving

Result

A security aspect Make a filter on the customer input Protection against cross scripting injection Result

Make a filter on the customer input

Protection against cross scripting injection

Result

S ingleton aspect All singletons are factorized in the same aspect The link between a class and its singleton is null

All singletons are factorized in the same aspect

The link between a class and its singleton is null

C urrent weaving chain

New features

N ew weaving chain

F eatures coming very soon Logicals operators: Enum operator: New joinpoints Reusable aspects mechanisms (with Smarty) Aspect introspection

Logicals operators:

Enum operator:

New joinpoints

Reusable aspects mechanisms (with Smarty)

Aspect introspection

W eb specifics joinpoints PHP has a lot of globals variables with very sensitives informations: $_GET, $_POST, $_COOKIE, $_SERVER, $_SESSION We need to intercept writing/reading of these for security matters. File joinpoint

PHP has a lot of globals variables with very sensitives informations:

$_GET, $_POST, $_COOKIE, $_SERVER, $_SESSION

We need to intercept writing/reading of these for security matters.

File joinpoint

P ersistence with phpAspect There is great tools existing for object persistence: Propel for example Problem: If you regenerate the classes, you lose your businesses operations Solution: generate an aspect of persistence with Propel from an aspect template and classes annotations

There is great tools existing for object persistence: Propel for example

Problem: If you regenerate the classes, you lose your businesses operations

Solution: generate an aspect of persistence with Propel from an aspect template and classes annotations

A spect DOM XPath is a way better than SQL for queries on tree structure. By weaving DOM interfaces we can use Xpath expressions on: your object graph in a visitor design pattern SQL Query : SELECT * FROM book, books, author WHERE books.idbook = {$_SESSION['id']} AND book.id = books.idbook AND book.author = author.id AND author.name = 'Alexandre Jardin' Xpath query : //author[@name = 'Alexandre Jardin']

XPath is a way better than SQL for queries on tree structure.

By weaving DOM interfaces we can use Xpath expressions on:

your object graph

in a visitor design pattern

SQL Query : SELECT * FROM book, books, author WHERE books.idbook = {$_SESSION['id']} AND book.id = books.idbook AND book.author = author.id AND author.name = 'Alexandre Jardin'

Xpath query : //author[@name = 'Alexandre Jardin']

A spects templates (1/2) Put parameters on aspects with Smarty A way to define generic and reusables aspects. Parameters based on the XML format. Aspect template construction: Parameters evaluation with Smarty Result: an aspect ready to be weaved

Put parameters on aspects with Smarty

A way to define generic and reusables aspects.

Parameters based on the XML format.

Aspect template construction:

Parameters evaluation with Smarty

Result: an aspect ready to be weaved

A spects templates (1/2) XML parameters: Template:

XML parameters:

Template:

L imitations Aspects composition Static weaving Debugging There is no PHP IDE having AOP features

Aspects composition

Static weaving

Debugging

There is no PHP IDE having AOP features

C onclusion phpAspect: Wiki: http://phpaspect.org Blog: http://wcandillon.blogspot.com Perspectives: PHP 6 ready (namespaces) Aspect composition Type inference Framework integration Looking for an internship: http://wcandillon.netcv.org

phpAspect:

Wiki: http://phpaspect.org

Blog: http://wcandillon.blogspot.com

Perspectives:

PHP 6 ready (namespaces)

Aspect composition

Type inference

Framework integration

Looking for an internship: http://wcandillon.netcv.org

R eferences AOSD community and projects: http://aosd.net AspectJ in action , by Ramnivas Laddad Mastering AspectJ , by John & Wiley, Joseph D. Gradecki, Nicholas Lesiecki Programmation Orientée Aspect pour Java , by Renaud Pawlak, Jean-Philippe Retaillé et Lionel Seinturier.

AOSD community and projects: http://aosd.net

AspectJ in action , by Ramnivas Laddad

Mastering AspectJ , by John & Wiley, Joseph D. Gradecki, Nicholas Lesiecki

Programmation Orientée Aspect pour Java , by Renaud Pawlak, Jean-Philippe Retaillé et Lionel Seinturier.

Demo

Questions ?