creating clean code with aop (webexpo 2010)
DESCRIPTION
OOP helps us creating a clearly laid out and intuitive model of the reality by means of objects. However, concerns like security, logging or transactions need to be implemented virtually anywhere, resulting in scattered error-prone code. Aspect-Oriented Programming separates these cross-cutting concerns from the rest of the code and lets you handle them in a well-known, central location.In this session you’ll get a first-hand introduction into FLOW3’s AOP implementation as well as related techniques such as Dependency Injection. You’ll be able to try out the examples given right after the presentation.FLOW3 is an application framework which was designed to be the foundation for the upcoming major version of TYPO3 CMS and in the meantime has become an Open-Source Project on its own. It brings a range of new development concepts to the PHP world which all aim for making development easier, faster and reduce complexity in big applications.TRANSCRIPT
WebExpo 2010, Prague
Robert Lemke
Create Clean Code with Aspect-Oriented Programming
Photo: Robert Szlivka
Robert Lemkechief architect of TYPO3 Phoenix and FLOW3
co-founder of the TYPO3 Association
34 years old
lives in Lübeck, Germany
1 wife, 1 daughter, 1 espresso machine
likes drumming
www.typo3.org
www.typo3.org
Create Clean Code with AOP WebExpo 2010, Prague
www.typo3.org
= PHP 5.3 Full Stack Application Framework
OOP Object-Oriented Programming
AOP Aspect-Oriented Programming
MVC Model View Controller
POPO Plain Old PHP Object
DI Dependency Injection DRY
YAGNI
CoC
TDD
YAA
Create Clean Code with AOP WebExpo 2010, Prague
/** * Creates a new post * * @param \F3\Blog\Domain\Model\Post $newPost A fresh Post object which has not yet been * added to the repository * @return void */public function createAction(\F3\Blog\Domain\Model\Post $newPost) { if ($this->policyService->isGranted($this->currentUser, __CLASS__, __METHOD__) { $this->blog->addPost($newPost); $this->flashMessageContainer->add('Your new post was created.'); $this->systemLogger->log('A new post was created.', LOG_INFO); $this->notificationService->notify('A new post was created.', '[email protected]'); } else { $this->systemLogger->log('Someone tried to create a post.', LOG_WARNING); throw new \F3\FLOW3\Security\Exception\AccessDeniedException('Tried to create.'); } $this->redirect('index');}
Create Clean Code with AOP WebExpo 2010, Prague
/** * Creates a new post * * @param \F3\Blog\Domain\Model\Post $newPost A fresh Post object which has not yet been * added to the repository * @return void */public function createAction(\F3\Blog\Domain\Model\Post $newPost) { if ($this->policyService->isGranted($this->currentUser, __CLASS__, __METHOD__) { $this->blog->addPost($newPost); $this->flashMessageContainer->add('Your new post was created.'); $this->systemLogger->log('A new post was created.', LOG_INFO); $this->notificationService->notify('A new post was created.', '[email protected]'); } else { $this->systemLogger->log('Someone tried to create a post.', LOG_WARNING); throw new \F3\FLOW3\Security\Exception\AccessDeniedException('Tried to create.'); } $this->redirect('index');}
Create Clean Code with AOP WebExpo 2010, Prague
Create Clean Code with AOP WebExpo 2010, Prague
AOP
Create Clean Code with AOP WebExpo 2010, Prague
Aspect-Oriented Programmingprogramming paradigm
separates concerns to improve modularization
OOP modularizes concerns into objects
AOP modularizes cross-cutting concerns into aspects
Create Clean Code with AOP WebExpo 2010, Prague
/** * Creates a new post * * @param \F3\Blog\Domain\Model\Post $newPost A fresh Post object which has not yet been * added to the repository * @return void */public function createAction(\F3\Blog\Domain\Model\Post $newPost) { $this->blog->addPost($newPost); $this->flashMessageContainer->add('Your new post was created.'); $this->redirect('index');}
Create Clean Code with AOP WebExpo 2010, Prague
Concerns?
Create Clean Code with AOP WebExpo 2010, Prague
ConcernsSeparation of Concerns
group features and behavior into manageable parts
have a specific purpose and business to take care of
Cross-Cutting Concerns
are the party poopers who want to have a say in everything
Create Clean Code with AOP WebExpo 2010, Prague
Cross-Cutting ConcernsLogging
Security
Persistence
Global Business Logic
Dirty Hacks
Create Clean Code with AOP WebExpo 2010, Prague
We don't want infrastructure codein our models.
Create Clean Code with AOP WebExpo 2010, Prague
We want to unit-test even cross-cutting concerns
Create Clean Code with AOP WebExpo 2010, Prague
We want to centralize security-related code
Create Clean Code with AOP WebExpo 2010, Prague
AOP Lingo
Create Clean Code with AOP WebExpo 2010, Prague
AspectPart of the application where cross-cutting concerns are implemented
In FLOW3 aspects are classes annotated with @aspect
Create Clean Code with AOP WebExpo 2010, Prague
Join PointIs a single point in the call graph
Method Execution
Exception
Represents an event, not a location
Create Clean Code with AOP WebExpo 2010, Prague
PointcutA set of join points where advices could be executed
can be composed
can be named
Create Clean Code with AOP WebExpo 2010, Prague
AdviceAction to take at a join points defined by the point cut
Inspiring people toshareHitchhiker's Guide to FLOW3
DEMO
Inspiring people toshareHitchhiker's Guide to FLOW3
Kinds of AdviceAdvice types supported by FLOW3:
@before@afterreturning@afterthrowing@after@around
Inspiring people toshareHitchhiker's Guide to FLOW3
Pointcut Designatorsmethod(F3\MyPackage\MyClass->myMethod())class(F3\MyPackage\MyClass)within(F3\MyPackage\MyInterface)classTaggedWith(someTag)methodTaggedWith(anotherTag)setting(Demo.Stuff.SomeSetting = "yeah, do it")ffiilter(F3\MyPackage\MyCustomFilterImplementation)
Inspiring people toshareHitchhiker's Guide to FLOW3
Runtime Evaluationsevaluate(coffee.kind == "Arabica")
Inspiring people toshareHitchhiker's Guide to FLOW3
Compound Pointcuts
! /**! * @around method(.*Controller->(new|create|edit|update|delete)Action()) && ⏎ !methodTaggedWith(anybodyMayAccessThis)! */! public function interceptMethodCalls($joinPoint) {
...}
Inspiring people toshareHitchhiker's Guide to FLOW3
DEMO
Inspiring people toshareHitchhiker's Guide to FLOW3
FLOW3's AOP implementationbased on proxy classes
unlike with most pre-processors line numbers stay the same
no scaffolding
0 Lines of generated code which need to be maintained by you
fast (on the second hit)
Inspiring people toshareHitchhiker's Guide to FLOW3
Inspiring people toshareHitchhiker's Guide to FLOW3
Create Clean Code with AOP WebExpo 2010, Prague
Progress
FLOW3 1.0.0
Create Clean Code with AOP WebExpo 2010, Prague
Further ReadingFLOW3 Websitehttp://flow3.typo3.org
FLOW3 Downloadhttp://flow3.typo3.org/downloadgit://git.typo3.org/FLOW3/Distributions/Base.git
TYPO3 Forgehttp://forge.typo3.org
Further Readinghttp://flow3.typo3.org/about/principles/further-reading
Create Clean Code with AOP WebExpo 2010, Prague
Questions
Email: [email protected]: http://robertlemke.de/blogTwitter: @t3rob
Slides: http://slideshare.net/rlmp