Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
Complex classes like Cache 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 Cache, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
||
| 17 | class Cache implements iCache |
||
| 18 | { |
||
| 19 | |||
| 20 | /** |
||
| 21 | * @var iAdapter |
||
| 22 | */ |
||
| 23 | private $adapter; |
||
| 24 | |||
| 25 | /** |
||
| 26 | * @var iSerializer |
||
| 27 | */ |
||
| 28 | private $serializer; |
||
| 29 | |||
| 30 | /** |
||
| 31 | * @var string |
||
| 32 | */ |
||
| 33 | private $prefix = ''; |
||
| 34 | |||
| 35 | /** |
||
| 36 | * @var bool |
||
| 37 | */ |
||
| 38 | private $isReady = false; |
||
| 39 | |||
| 40 | /** |
||
| 41 | * @var bool |
||
| 42 | */ |
||
| 43 | private $isActive = true; |
||
| 44 | |||
| 45 | /** |
||
| 46 | * @var mixed no cache, if admin-session is set |
||
| 47 | */ |
||
| 48 | private $isAdminSession = false; |
||
| 49 | |||
| 50 | /** |
||
| 51 | * __construct |
||
| 52 | * |
||
| 53 | * @param null|iAdapter $adapter |
||
| 54 | * @param null|iSerializer $serializer |
||
| 55 | * @param boolean $checkForUser check for dev-ip or if cms-user is logged-in |
||
| 56 | * @param boolean $cacheEnabled false will disable the cache (use it e.g. for global settings) |
||
| 57 | * @param string|boolean $isAdminSession set a user-id, if the user is a admin (so we can disable cache for this user) |
||
| 58 | */ |
||
| 59 | 27 | public function __construct($adapter = null, $serializer = null, $checkForUser = true, $cacheEnabled = true, $isAdminSession = false) |
|
| 60 | { |
||
| 61 | 27 | $this->isAdminSession = $isAdminSession; |
|
| 62 | |||
| 63 | // check for active-cache |
||
| 64 | 27 | $this->setActive($cacheEnabled); |
|
| 65 | 27 | if ($this->isActive === true && $checkForUser === true) { |
|
| 66 | $this->setActive($this->isCacheActiveForTheCurrentUser()); |
||
| 67 | } |
||
| 68 | |||
| 69 | 27 | if ($this->isActive === true) { |
|
| 70 | |||
| 71 | 27 | $this->setPrefix($this->getTheDefaultPrefix()); |
|
| 72 | |||
| 73 | if ( |
||
| 74 | $adapter === null |
||
| 75 | 27 | || |
|
| 76 | 27 | !is_object($adapter) |
|
| 77 | 27 | || |
|
| 78 | !$adapter instanceof iAdapter |
||
| 79 | 27 | ) { |
|
| 80 | $adapter = $this->autoConnectToAvailableCacheSystem(); |
||
| 81 | } |
||
| 82 | |||
| 83 | // Memcache(d) has his own "serializer", but it seems to be working different as the php-implementation. |
||
| 84 | 27 | if (!is_object($serializer) && $serializer === null) { |
|
| 85 | $serializer = new SerializerIgbinary(); |
||
| 86 | } |
||
| 87 | 27 | } |
|
| 88 | |||
| 89 | // check if we will use the cache |
||
| 90 | if ( |
||
| 91 | 1 | $serializer instanceof iSerializer |
|
| 92 | 27 | && |
|
| 93 | $adapter instanceof iAdapter |
||
| 94 | 27 | ) { |
|
| 95 | 27 | $this->setCacheIsReady(true); |
|
| 96 | |||
| 97 | 27 | $this->adapter = $adapter; |
|
| 98 | 27 | $this->serializer = $serializer; |
|
| 99 | 27 | } |
|
| 100 | 27 | } |
|
| 101 | |||
| 102 | /** |
||
| 103 | * enable / disable the cache |
||
| 104 | * |
||
| 105 | * @param boolean $isActive |
||
| 106 | */ |
||
| 107 | 27 | public function setActive($isActive) |
|
| 108 | { |
||
| 109 | 27 | $this->isActive = (boolean)$isActive; |
|
| 110 | 27 | } |
|
| 111 | |||
| 112 | /** |
||
| 113 | * check if the current use is a admin || dev || server == client |
||
| 114 | * |
||
| 115 | * @return bool |
||
| 116 | */ |
||
| 117 | public function isCacheActiveForTheCurrentUser() |
||
| 118 | { |
||
| 119 | $active = true; |
||
| 120 | |||
| 121 | // test the cache, with this GET-parameter |
||
| 122 | $testCache = isset($_GET['testCache']) ? (int)$_GET['testCache'] : 0; |
||
| 123 | |||
| 124 | if ($testCache != 1) { |
||
| 125 | if ( |
||
| 126 | // server == client |
||
| 127 | ( |
||
| 128 | isset($_SERVER['SERVER_ADDR']) |
||
| 129 | && |
||
| 130 | $_SERVER['SERVER_ADDR'] == $this->getClientIp() |
||
| 131 | ) |
||
| 132 | || |
||
| 133 | // admin is logged-in |
||
| 134 | $this->isAdminSession |
||
| 135 | || |
||
| 136 | // user is a dev |
||
| 137 | $this->checkForDev() === true |
||
| 138 | ) { |
||
| 139 | $active = false; |
||
| 140 | } |
||
| 141 | } |
||
| 142 | |||
| 143 | return $active; |
||
| 144 | } |
||
| 145 | |||
| 146 | /** |
||
| 147 | * returns the IP address of the client |
||
| 148 | * |
||
| 149 | * @param bool $trust_proxy_headers Whether or not to trust the |
||
| 150 | * proxy headers HTTP_CLIENT_IP |
||
| 151 | * and HTTP_X_FORWARDED_FOR. ONLY |
||
| 152 | * use if your $_SERVER is behind a |
||
| 153 | * proxy that sets these values |
||
| 154 | * |
||
| 155 | * @return string |
||
| 156 | */ |
||
| 157 | private function getClientIp($trust_proxy_headers = false) |
||
| 158 | { |
||
| 159 | $remoteAddr = isset($_SERVER['REMOTE_ADDR']) ? $_SERVER['REMOTE_ADDR'] : 'NO_REMOTE_ADDR'; |
||
| 160 | |||
| 161 | if ($trust_proxy_headers) { |
||
| 162 | return $remoteAddr; |
||
| 163 | } |
||
| 164 | |||
| 165 | if (isset($_SERVER['HTTP_CLIENT_IP']) && $_SERVER['HTTP_CLIENT_IP']) { |
||
| 166 | $ip = $_SERVER['HTTP_CLIENT_IP']; |
||
| 167 | } elseif (isset($_SERVER['HTTP_X_FORWARDED_FOR']) && $_SERVER['HTTP_X_FORWARDED_FOR']) { |
||
| 168 | $ip = $_SERVER['HTTP_X_FORWARDED_FOR']; |
||
| 169 | } else { |
||
| 170 | $ip = $remoteAddr; |
||
| 171 | } |
||
| 172 | |||
| 173 | return $ip; |
||
| 174 | } |
||
| 175 | |||
| 176 | /** |
||
| 177 | * check for developer |
||
| 178 | * |
||
| 179 | * @return bool |
||
| 180 | */ |
||
| 181 | private function checkForDev() |
||
| 182 | { |
||
| 183 | $return = false; |
||
| 184 | |||
| 185 | if (function_exists('checkForDev')) { |
||
| 186 | $return = checkForDev(); |
||
| 187 | } else { |
||
| 188 | |||
| 189 | // for testing with dev-address |
||
| 190 | $noDev = isset($_GET['noDev']) ? (int)$_GET['noDev'] : 0; |
||
| 191 | $remoteAddr = isset($_SERVER['REMOTE_ADDR']) ? $_SERVER['REMOTE_ADDR'] : 'NO_REMOTE_ADDR'; |
||
| 192 | |||
| 193 | if ( |
||
| 194 | $noDev != 1 |
||
| 195 | && |
||
| 196 | ( |
||
| 197 | $remoteAddr == '127.0.0.1' |
||
| 198 | || |
||
| 199 | $remoteAddr == '::1' |
||
| 200 | || |
||
| 201 | PHP_SAPI == 'cli' |
||
| 202 | ) |
||
| 203 | ) { |
||
| 204 | $return = true; |
||
| 205 | } |
||
| 206 | } |
||
| 207 | |||
| 208 | return $return; |
||
| 209 | } |
||
| 210 | |||
| 211 | /** |
||
| 212 | * set the default-prefix via "SERVER_NAME" + "SESSION"-language |
||
| 213 | */ |
||
| 214 | 27 | protected function getTheDefaultPrefix() |
|
| 215 | { |
||
| 216 | 27 | return (isset($_SERVER['SERVER_NAME']) ? $_SERVER['SERVER_NAME'] : '') . '_' . (isset($_SESSION['language']) ? $_SESSION['language'] : '') . '_' . (isset($_SESSION['language_extra']) ? $_SESSION['language_extra'] : ''); |
|
| 217 | } |
||
| 218 | |||
| 219 | /** |
||
| 220 | * auto-connect to the available cache-system on the server |
||
| 221 | * |
||
| 222 | * @return iAdapter |
||
| 223 | */ |
||
| 224 | protected function autoConnectToAvailableCacheSystem() |
||
| 225 | { |
||
| 226 | static $adapterCache; |
||
| 227 | |||
| 228 | if (is_object($adapterCache) && $adapterCache instanceof iAdapter) { |
||
| 229 | return $adapterCache; |
||
| 230 | } else { |
||
| 231 | |||
| 232 | $memcached = null; |
||
| 233 | $isMemcachedAvailable = false; |
||
| 234 | if (extension_loaded('memcached')) { |
||
| 235 | $memcached = new \Memcached(); |
||
| 236 | $isMemcachedAvailable = $memcached->addServer('127.0.0.1', '11211'); |
||
| 237 | } |
||
| 238 | |||
| 239 | if ($isMemcachedAvailable === false) { |
||
| 240 | $memcached = null; |
||
| 241 | } |
||
| 242 | |||
| 243 | $adapterMemcached = new AdapterMemcached($memcached); |
||
| 244 | if ($adapterMemcached->installed() === true) { |
||
| 245 | |||
| 246 | // fallback to Memcached |
||
| 247 | $adapter = $adapterMemcached; |
||
| 248 | |||
| 249 | } else { |
||
| 250 | |||
| 251 | $memcache = null; |
||
| 252 | $isMemcacheAvailable = false; |
||
| 253 | if (class_exists('\Memcache')) { |
||
| 254 | $memcache = new \Memcache; |
||
| 255 | /** @noinspection PhpUsageOfSilenceOperatorInspection */ |
||
| 256 | $isMemcacheAvailable = @$memcache->connect('127.0.0.1', 11211); |
||
| 257 | } |
||
| 258 | |||
| 259 | if ($isMemcacheAvailable === false) { |
||
| 260 | $memcache = null; |
||
| 261 | } |
||
| 262 | |||
| 263 | $adapterMemcache = new AdapterMemcache($memcache); |
||
| 264 | if ($adapterMemcache->installed() === true) { |
||
| 265 | |||
| 266 | // fallback to Memcache |
||
| 267 | $adapter = $adapterMemcache; |
||
| 268 | |||
| 269 | } else { |
||
| 270 | |||
| 271 | $redis = null; |
||
| 272 | $isRedisAvailable = false; |
||
| 273 | if (extension_loaded('redis')) { |
||
| 274 | if (class_exists('\Predis\Client')) { |
||
| 275 | $redis = new \Predis\Client( |
||
| 276 | array( |
||
| 277 | 'scheme' => 'tcp', |
||
| 278 | 'host' => '127.0.0.1', |
||
| 279 | 'port' => 6379, |
||
| 280 | 'timeout' => '2.0', |
||
| 281 | ) |
||
| 282 | ); |
||
| 283 | try { |
||
| 284 | $redis->connect(); |
||
| 285 | $isRedisAvailable = $redis->getConnection()->isConnected(); |
||
| 286 | } catch (\Exception $e) { |
||
| 287 | // nothing |
||
| 288 | } |
||
| 289 | } |
||
| 290 | } |
||
| 291 | |||
| 292 | if ($isRedisAvailable === false) { |
||
| 293 | $redis = null; |
||
| 294 | } |
||
| 295 | |||
| 296 | $adapterRedis = new AdapterPredis($redis); |
||
| 297 | if ($adapterRedis->installed() === true) { |
||
| 298 | |||
| 299 | // fallback to Redis |
||
| 300 | $adapter = $adapterRedis; |
||
| 301 | |||
| 302 | } else { |
||
| 303 | |||
| 304 | $adapterXcache = new AdapterXcache(); |
||
| 305 | if ($adapterXcache->installed() === true) { |
||
| 306 | |||
| 307 | // fallback to Xcache |
||
| 308 | $adapter = $adapterXcache; |
||
| 309 | |||
| 310 | } else { |
||
| 311 | |||
| 312 | $adapterApc = new AdapterApc(); |
||
| 313 | if ($adapterApc->installed() === true) { |
||
| 314 | |||
| 315 | // fallback to APC || APCu |
||
| 316 | $adapter = $adapterApc; |
||
| 317 | |||
| 318 | } else { |
||
| 319 | |||
| 320 | $adapterFile = new AdapterFile(); |
||
| 321 | if ($adapterFile->installed() === true) { |
||
| 322 | |||
| 323 | // fallback to File-Cache |
||
| 324 | $adapter = $adapterFile; |
||
| 325 | |||
| 326 | } else { |
||
| 327 | // no cache-adapter available -> use a array |
||
| 328 | $adapter = new AdapterArray(); |
||
| 329 | } |
||
| 330 | } |
||
| 331 | } |
||
| 332 | } |
||
| 333 | } |
||
| 334 | } |
||
| 335 | |||
| 336 | // save to static cache |
||
| 337 | $adapterCache = $adapter; |
||
| 338 | } |
||
| 339 | |||
| 340 | return $adapter; |
||
| 341 | } |
||
| 342 | |||
| 343 | /** |
||
| 344 | * set cacheIsReady state |
||
| 345 | * |
||
| 346 | * @param boolean $isReady |
||
| 347 | */ |
||
| 348 | 27 | private function setCacheIsReady($isReady) |
|
| 352 | |||
| 353 | /** |
||
| 354 | * get the cacheIsReady state |
||
| 355 | * |
||
| 356 | * @return boolean |
||
| 357 | */ |
||
| 358 | 3 | public function getCacheIsReady() |
|
| 362 | |||
| 363 | /** |
||
| 364 | * get cached-item by key |
||
| 365 | * |
||
| 366 | * @param string $key |
||
| 367 | * |
||
| 368 | * @return mixed |
||
| 369 | */ |
||
| 370 | 12 | public function getItem($key) |
|
| 383 | |||
| 384 | /** |
||
| 385 | * calculate store-key (prefix + $rawKey) |
||
| 386 | * |
||
| 387 | * @param String $rawKey |
||
| 388 | * |
||
| 389 | * @return string |
||
| 390 | */ |
||
| 391 | 23 | private function calculateStoreKey($rawKey) |
|
| 395 | |||
| 396 | /** |
||
| 397 | * @return mixed |
||
| 398 | */ |
||
| 399 | 23 | public function getPrefix() |
|
| 403 | |||
| 404 | /** |
||
| 405 | * set prefix [WARNING: do not use if you don't know what you do] |
||
| 406 | * |
||
| 407 | * @param string $prefix |
||
| 408 | */ |
||
| 409 | 27 | public function setPrefix($prefix) |
|
| 413 | |||
| 414 | /** |
||
| 415 | * set cache-item by key => value + date |
||
| 416 | * |
||
| 417 | * @param string $key |
||
| 418 | * @param mixed $value |
||
| 419 | * @param \DateTime $date |
||
| 420 | * |
||
| 421 | * @return mixed|void |
||
| 422 | * @throws \Exception |
||
| 423 | */ |
||
| 424 | 5 | public function setItemToDate($key, $value, \DateTime $date) |
|
| 436 | |||
| 437 | /** |
||
| 438 | * set cache-item by key => value + ttl |
||
| 439 | * |
||
| 440 | * @param string $key |
||
| 441 | * @param mixed $value |
||
| 442 | * @param int $ttl |
||
| 443 | * |
||
| 444 | * @return bool |
||
| 445 | */ |
||
| 446 | 12 | public function setItem($key, $value, $ttl = 0) |
|
| 466 | |||
| 467 | /** |
||
| 468 | * remove cached-item |
||
| 469 | * |
||
| 470 | * @param string $key |
||
| 471 | * |
||
| 472 | * @return bool |
||
| 473 | */ |
||
| 474 | 1 | View Code Duplication | public function removeItem($key) |
| 484 | |||
| 485 | /** |
||
| 486 | * check if cached-item exists |
||
| 487 | * |
||
| 488 | * @param string $key |
||
| 489 | * |
||
| 490 | * @return boolean |
||
| 491 | */ |
||
| 492 | 4 | View Code Duplication | public function existsItem($key) |
| 502 | |||
| 503 | } |
||
| 504 |
Instead of super-globals, we recommend to explicitly inject the dependencies of your class. This makes your code less dependent on global state and it becomes generally more testable: