Dependency Injection with PHP

Transcript

1. Dependency Injection with PHP @BastianHofmann

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6. Dependency Injection Dependency Injection Containers Dependency Inversion Dependencies

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9. ResearchGate gives science back to the people who make it

   happen. We help researchers build reputation and accelerate scientific progress. On their terms. ‟
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17. Questions? Ask!

18. http://speakerdeck.com/u/bastianhofmann

19. Dependency Inversion

20. http://www.doolwind.com/blog/solid-principles-for-game-developers/

21. http://qafoo.com/presentations.html

22. http://www.doolwind.com/blog/solid-principles-for-game-developers/

23. High-level modules should not depend on low level modules but

    on abstractions. ”

24. A B C

25. A B C <<interface>> <<interface>>

26. A B C <<interface>>

27. A B Adapter <<interface>> C

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30. Dependency Injection

31. Constructor

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34. Setter

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36. Method argument

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38. Constructing classes

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40. Benefits

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42. Easier to change

43. Easier testing

44. Only test the class, not the dependencies

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46. Mocking

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49. http://www.doolwind.com/blog/solid-principles-for-game-developers/

50. But...

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52. Make it easier with factories

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54. Dependency Injection Container

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56. rg\injektor inspired by google-guice

57. https://github.com/researchgate/injektor

58. http://getcomposer.org/ http://packagist.org/

59. $ cat composer.json

60. $ wget http://getcomposer.org/composer.phar $ php composer.phar install Installing dependencies -

    Installing monolog/monolog (1.1.0) Downloading: 100% ... monolog/monolog suggests installing mlehner/ gelf-php (Allow sending log messages to a GrayLog2 server) Writing lock file Generating autoload files
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62. Creating an instance of a class

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66. PHP 5.5

67. Automatic creation of dependencies through Typehints

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69. @inject

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71. What classes can be injected?

72. No constructor

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74. Constructor without arguments

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76. Constructor with arguments that have default values

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78. Injectable constructor

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81. By the way: Property Injection

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83. Singletons with public static getInstance method following the same rules

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85. STOP: Don‘t use Singeltons

86. Singletons are evil!

87. Let the DIC take care of instances

88. @singleton

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90. Passing additional, fixed values to instance

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92. Working with Interfaces

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94. But we can not create an instance of an Interface!

95. @implementedBy

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97. Named @implementedBy

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100. Providers

101. @providedBy

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104. Method invocation at DIC

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106. Same rules

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109. And if you don‘t like annotations... ... or want to

     integrate 3rd party code
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112. Great! So, how does it work?

113. Development: Reflection

114. Production: Generated Factory Classes

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117. https://github.com/bashofmann/dic_demo/

118. DEMO

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120. https://github.com/symfony/DependencyInjection

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124. https://github.com/bashofmann/dic_demo/

125. DEMO

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127. https://github.com/zendframework/zf2

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130. Automatic creation of dependencies through Typehints

131. https://github.com/bashofmann/dic_demo/

132. DEMO

133. AOP

134. http://flow3.typo3.org/documentation/guide/partiii/ aspectorientedprogramming.html

135. class  Forum  {    /**      *  @FLOW3\Inject  

        *  @var  ApplicationLoggerInterface      */    protected  $applicationLogger;    /**      *  @param  Post  $post      *  @return  void      */    public  function  deletePost(Post  $post)  {        $this-­‐>applicationLogger-­‐>log('Removing  post');        $this-­‐>posts-­‐>remove($post);    } }

136. class  Forum  {    /**      *  Delete  a

      forum  post      *      *  @param  Post  $post      *  @return  void      */    public  function  deletePost(Post  $post)  {        $this-­‐>posts-­‐>remove($post);    } }

137. /**  *  @FLOW3\Aspect  */ class  LoggingAspect  {    /**  

        *  @FLOW3\Inject      *  @var  ApplicationLoggerInterface      */    protected  $applicationLogger;    /**      *  @FLOW3\Before("method(Forum-­‐>deletePost())")      */    public  function  logDeletePost(\TYPO3\FLOW3\AOP \JoinPointInterface  $joinPoint)  {        $post  =  $joinPoint-­‐>getMethodArgument('post');        $this-­‐>applicationLogger-­‐>log('Removing');    } }
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139. h"p://twi"er.com/Bas2anHofmann h"p://profiles.google.com/bashofmann h"p://lanyrd.com/people/Bas2anHofmann h"p://speakerdeck.com/u/bas2anhofmann h"ps://github.com/bashofmann [email protected] Did you like this

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