It's my way or the highway - How to make your code usable by others

Having documentation when using a piece of code you didn’t write is nice, but usually it’s not that hard to mess something up/missuse it. Using some basic OOP principles we can enforce proper use of our code onto developers who are using it, and greatly reduce someones time when implementing something for the first time, while increasing the quality of the code.

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1. Bogdan Habić bogdan@norm.rs @BogdanHabic WebCamp - Ljubljana - 2015
2. How to use just enough transitions in your presentations
3. It's my way or the highway How to make your code usable by others
4. • Encapsulation • Inheritance • Polymorphism
5. Source: https://github.com/sugarcrm/sugarcrm_dev/blob/master/include/MVC/View/SugarView.php#L705-L708
6. function doWork2(idLinije) { httpObject = GetXmlHttpObject(); if (httpObject != null) { var url = "comboLinije.php" //url = url + "?idLinije=" + idLinije; //url= url + "&smer" + smer; url = url + "?kodLinije=" + idLinije httpObject.open("GET", url ,true); httpObject.send(null); httpObject.onreadystatechange = setOutput2; } }
7. Why does it come to this?
8. • Cowboy coding • Tight deadlines • “ I’ll refactor this later ”
9. How to fix this?
10. You won't refactor later
11. • DRY • SOLID • Design patterns
13. What makes a piece of code: “ Nice to use ”
14. Easy to implement
15. It’s eloquent
16. Works like magic
17. How to make magic?
18. How to make magic? (happen)
19. The developer should not care about the internals
20. The code should “ lead “ the developer
21. It should be modular
22. • Interfaces • Abstract classes • Traits • Exceptions
23. • Strategy • Command Handler
24. Interfaces
25. Source: http://geog.ufl.edu/files/too-much-information-forms.jpg
26. Source: http://geog.ufl.edu/files/too-much-information-forms.jpg Here is all the paperwork needed.
27. interface StringDecorator { /** * Decorates the string. * * @param string $string * @return string */ public function decorate($string); }
28. • Known parameter types • Known return types • It’s self explanatory
29. Abstract classes
30. abstract class RegexDecorator implements StringDecorator { protected $regularExpression; protected $replacement; public final function __construct() { $this->regularExpression = $this->getRegularExpression(); $this->replacement = $this->getReplacement(); } public abstract function getRegularExpression(); public abstract function getReplacement(); protected function replace($string) { return preg_replace($this->regularExpression, $this->replacement, $string); } public function decorate($string) { return $this->replace($string); } }
31. abstract class RegexDecorator implements StringDecorator { protected $regularExpression; protected $replacement; public final function __construct() { $this->regularExpression = $this->getRegularExpression(); $this->replacement = $this->getReplacement(); } public abstract function getRegularExpression(); public abstract function getReplacement(); protected function replace($string) { return preg_replace($this->regularExpression, $this->replacement, $string); } public function decorate($string) { return $this->replace($string); } }
32. abstract class RegexDecorator implements StringDecorator { protected $regularExpression; protected $replacement; public final function __construct() { $this->regularExpression = $this->getRegularExpression(); $this->replacement = $this->getReplacement(); } public abstract function getRegularExpression(); public abstract function getReplacement(); protected function replace($string) { return preg_replace($this->regularExpression, $this->replacement, $string); } public function decorate($string) { return $this->replace($string); } }
33. abstract class RegexDecorator implements StringDecorator { protected $regularExpression; protected $replacement; public final function __construct() { $this->regularExpression = $this->getRegularExpression(); $this->replacement = $this->getReplacement(); } public abstract function getRegularExpression(); public abstract function getReplacement(); protected function replace($string) { return preg_replace($this->regularExpression, $this->replacement, $string); } public function decorate($string) { return $this->replace($string); } }
34. abstract class RegexDecorator implements StringDecorator { protected $regularExpression; protected $replacement; public final function __construct() { $this->regularExpression = $this->getRegularExpression(); $this->replacement = $this->getReplacement(); } public abstract function getRegularExpression(); public abstract function getReplacement(); protected function replace($string) { return preg_replace($this->regularExpression, $this->replacement, $string); } public function decorate($string) { return $this->replace($string); } }
35. abstract class RegexDecorator implements StringDecorator { protected $regularExpression; protected $replacement; public final function __construct() { $this->regularExpression = $this->getRegularExpression(); $this->replacement = $this->getReplacement(); } public abstract function getRegularExpression(); public abstract function getReplacement(); protected function replace($string) { return preg_replace($this->regularExpression, $this->replacement, $string); } public function decorate($string) { return $this->replace($string); } }
36. • Forced to declare attributes • Known parameter types • Known return types • It’s self explanatory
37. Traits
38. trait StringDecoratorTrait { public function decorate($string) { foreach($this->getDecorators() as $decorator) { $decoratorInstance = new $decorator(); $string = $decoratorInstance->decorate($string); } return $string; } abstract public function getDecorators(); }
39. class MyDecoratorQueue { use StringDecoratorTrait; public function getDecorators() { return [ 'App\Decorators\FirstCapitalLetter', 'App\Decorators\ReplaceSpacesWithUnderscores', 'App\Decorators\LastLetterSmall', ]; } }
40. • It’s modular • It’s extendible • It’s simple
41. Exceptions
42. It’s OK to break someones code
43. public function decorate($string) { foreach($this->getDecorators() as $decorator) { $decoratorInstance = new $decorator(); $string = $decoratorInstance->decorate($string); if(!is_string($string)) throw new Exception(“The return value should be a string”); } return $string; }
44. Timing
45. Buzz word stage "optimization", “modular”, “redundancy” etc.
46. Death march stage
48. Strategy
49. Command Handler
50. bogdan@norm.rs @BogdanHabic Quesitions?