Complex classes like Router often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Router, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 20 | class Router |
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| 21 | { |
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| 22 | /** |
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| 23 | * Requested route |
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| 24 | * |
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| 25 | * @var string |
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| 26 | */ |
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| 27 | protected $path; |
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| 28 | |||
| 29 | |||
| 30 | /** |
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| 31 | * HTTP verb |
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| 32 | * |
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| 33 | * @var string |
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| 34 | */ |
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| 35 | protected $verb; |
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| 36 | |||
| 37 | |||
| 38 | /** |
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| 39 | * Installed routes |
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| 40 | * |
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| 41 | * @var array |
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| 42 | */ |
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| 43 | protected $routes = []; |
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| 44 | |||
| 45 | |||
| 46 | /** |
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| 47 | * Logger |
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| 48 | * |
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| 49 | * @var Logger |
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| 50 | */ |
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| 51 | protected $logger; |
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| 52 | |||
| 53 | |||
| 54 | /** |
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| 55 | * Init router |
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| 56 | * |
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| 57 | * @param array $server |
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| 58 | * @param Logger $logger |
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| 59 | * @return void |
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| 60 | */ |
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| 61 | public function __construct(array $server, Logger $logger) |
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| 73 | |||
| 74 | |||
| 75 | /** |
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| 76 | * Prepend route |
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| 77 | * |
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| 78 | * @param Route $route |
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| 79 | * @return Router |
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| 80 | */ |
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| 81 | public function prependRoute(Route $route): Router |
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| 87 | |||
| 88 | |||
| 89 | /** |
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| 90 | * Add route |
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| 91 | * |
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| 92 | * @param Route $route |
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| 93 | * @return Router |
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| 94 | */ |
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| 95 | public function addRoute(Route $route): Router |
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| 101 | |||
| 102 | |||
| 103 | /** |
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| 104 | * Clear routing table |
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| 105 | * |
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| 106 | * @return Router |
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| 107 | */ |
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| 108 | public function clearRoutingTable(): Router |
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| 113 | |||
| 114 | |||
| 115 | /** |
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| 116 | * Get active routes |
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| 117 | * |
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| 118 | * @return array |
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| 119 | */ |
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| 120 | public function getRoutes(): array |
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| 124 | |||
| 125 | |||
| 126 | /** |
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| 127 | * Set HTTP verb |
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| 128 | * |
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| 129 | * @param string $verb |
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| 130 | * @return Router |
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| 131 | */ |
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| 132 | public function setVerb(string $verb): Router |
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| 137 | |||
| 138 | |||
| 139 | /** |
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| 140 | * Get http verb |
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| 141 | * |
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| 142 | * @return string |
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| 143 | */ |
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| 144 | public function getVerb(): string |
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| 148 | |||
| 149 | |||
| 150 | /** |
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| 151 | * Set routing path |
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| 152 | * |
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| 153 | * @param string $path |
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| 154 | * @return Router |
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| 155 | */ |
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| 156 | public function setPath(string $path): Router |
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| 162 | |||
| 163 | |||
| 164 | /** |
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| 165 | * Get path |
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| 166 | * |
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| 167 | * @return string |
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| 168 | */ |
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| 169 | public function getPath(): string |
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| 173 | |||
| 174 | |||
| 175 | /** |
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| 176 | * Build method name |
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| 177 | * |
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| 178 | * @param string $name |
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| 179 | * @return string |
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| 180 | */ |
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| 181 | protected function _buildMethodName(string $name): string |
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| 191 | |||
| 192 | |||
| 193 | /** |
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| 194 | * Execute router |
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| 195 | * |
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| 196 | * @param array $constructor |
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| 197 | * @return bool |
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| 198 | */ |
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| 199 | public function run(array $constructor=[]): bool |
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| 252 | |||
| 253 | |||
| 254 | /** |
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| 255 | * Sends a exception response to the client |
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| 256 | * |
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| 257 | * @param \Exception $exception |
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| 258 | * @return void |
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| 259 | */ |
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| 260 | public function sendException(\Exception $exception): void |
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| 298 | |||
| 299 | |||
| 300 | /** |
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| 301 | * Check if method got params and combine these with |
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| 302 | * $_REQUEST |
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| 303 | * |
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| 304 | * @param string $class |
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| 305 | * @param string $method |
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| 306 | * @param array $parsed_params |
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| 307 | * @return array |
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| 308 | */ |
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| 309 | protected function getParams(string $class, string $method, array $parsed_params): array |
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| 379 | } |
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| 380 |
Let’s assume that you have a directory layout like this:
. |-- OtherDir | |-- Bar.php | `-- Foo.php `-- SomeDir `-- Foo.phpand let’s assume the following content of
Bar.php:If both files
OtherDir/Foo.phpandSomeDir/Foo.phpare loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.phpHowever, as
OtherDir/Foo.phpdoes not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: