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 Validation 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 Validation, and based on these observations, apply Extract Interface, too.
| 1 | <?php | ||
| 13 | class Validation { | ||
|  | |||
| 14 | |||
| 15 | /** | ||
| 16 | * validation errors | ||
| 17 | * | ||
| 18 | * | ||
| 19 | * @var array | ||
| 20 | */ | ||
| 21 | private $errors = []; | ||
| 22 | |||
| 23 | /** | ||
| 24 | * Custom rule messages. | ||
| 25 | * | ||
| 26 | * @var array | ||
| 27 | */ | ||
| 28 | private $ruleMessages = []; | ||
| 29 | |||
| 30 | /** | ||
| 31 | * Start the validation using values and rules passed in $data | ||
| 32 | * | ||
| 33 | * @param array $data | ||
| 34 | * @param bool $skip To skip validations as soon as one of the rules fails. | ||
| 35 | * | ||
| 36 | * @throws Exception if rule method doesn't exist | ||
| 37 | * @return bool | ||
| 38 | */ | ||
| 39 |     public function validate($data, $skip = false){ | ||
| 97 | |||
| 98 | /** | ||
| 99 | * Determine if a given value is empty, | ||
| 100 | * excluding '0', false, 0, 0.0, and files uploaded with UPLOAD_ERR_NO_FILE error, | ||
| 101 | * because these could be perfectly valid values, | ||
| 102 | * then, the validation methods has to decide if this value is valid or not. | ||
| 103 | * | ||
| 104 | * @param mixed $value | ||
| 105 | * @return bool | ||
| 106 | * | ||
| 107 | */ | ||
| 108 |     private function isEmpty($value){ | ||
| 124 | |||
| 125 | /** | ||
| 126 | * Determine if a given rules has 'required' rule | ||
| 127 | * | ||
| 128 | * @param array $rules | ||
| 129 | * @return bool | ||
| 130 | */ | ||
| 131 |     private function isRequired($rules){ | ||
| 134 | |||
| 135 | /** | ||
| 136 | * Determine if a given rule has arguments, Ex: max(4) | ||
| 137 | * | ||
| 138 | * @param string $rule | ||
| 139 | * @return bool | ||
| 140 | */ | ||
| 141 |     private function isruleHasArgs($rule) { | ||
| 144 | |||
| 145 | /** | ||
| 146 | * get rule name for rules that have args | ||
| 147 | * | ||
| 148 | * @param string $rule | ||
| 149 | * @return string | ||
| 150 | */ | ||
| 151 |     private function getRuleName($rule){ | ||
| 154 | |||
| 155 | /** | ||
| 156 | * get arguments for rules that have args | ||
| 157 | * | ||
| 158 | * @param string $rule | ||
| 159 | * @return array | ||
| 160 | */ | ||
| 161 |     private  function getRuleArgs($rule){ | ||
| 173 | |||
| 174 | /** | ||
| 175 | * Add a custom rule message. | ||
| 176 | * This message will be displayed instead of default. | ||
| 177 | * | ||
| 178 | * @param string $rule | ||
| 179 | * @param string $message | ||
| 180 | * @return array | ||
| 181 | */ | ||
| 182 |     public function addRuleMessage($rule, $message){ | ||
| 185 | |||
| 186 | /** | ||
| 187 | * Add an error | ||
| 188 | * | ||
| 189 | * @param string $rule | ||
| 190 | * @param string $placeholder for field | ||
| 191 | * @param mixed $value | ||
| 192 | * @param array $args | ||
| 193 | * | ||
| 194 | */ | ||
| 195 |     private function addError($rule, $placeholder, $value, $args = []){ | ||
| 232 | |||
| 233 | /** | ||
| 234 | * Checks if validation has passed. | ||
| 235 | * | ||
| 236 | * @return bool | ||
| 237 | */ | ||
| 238 |     public function passes(){ | ||
| 241 | |||
| 242 | /** | ||
| 243 | * get all errors | ||
| 244 | * | ||
| 245 | * @return array | ||
| 246 | */ | ||
| 247 |     public function errors(){ | ||
| 250 | |||
| 251 | /** | ||
| 252 | * clear all existing errors | ||
| 253 | * | ||
| 254 | * @return bool | ||
| 255 | */ | ||
| 256 |     public function clearErrors(){ | ||
| 259 | |||
| 260 | /** *********************************************** **/ | ||
| 261 | /** ************** Validations ************** **/ | ||
| 262 | /** *********************************************** **/ | ||
| 263 | |||
| 264 | /** | ||
| 265 | * Is value not empty? | ||
| 266 | * | ||
| 267 | * @param mixed $value | ||
| 268 | * @return bool | ||
| 269 | */ | ||
| 270 |     /*private function required($value){ | ||
| 271 | return !$this->isEmpty($value); | ||
| 272 | }*/ | ||
| 273 | |||
| 274 | /** | ||
| 275 | * min string length | ||
| 276 | * | ||
| 277 | * @param string $str | ||
| 278 | * @param array $args(min) | ||
| 279 | * | ||
| 280 | * @return bool | ||
| 281 | */ | ||
| 282 |     private function minLen($str, $args){ | ||
| 285 | |||
| 286 | /** | ||
| 287 | * max string length | ||
| 288 | * | ||
| 289 | * @param string $str | ||
| 290 | * @param array $args(max) | ||
| 291 | * | ||
| 292 | * @return bool | ||
| 293 | */ | ||
| 294 |     private function maxLen($str, $args){ | ||
| 297 | |||
| 298 | /** | ||
| 299 | * check if number between given range of numbers | ||
| 300 | * | ||
| 301 | * @param int $num | ||
| 302 | * @param array $args(min,max) | ||
| 303 | * @return bool | ||
| 304 | */ | ||
| 305 |     private function rangeNum($num, $args){ | ||
| 308 | |||
| 309 | /** | ||
| 310 | * check if value is a valid number | ||
| 311 | * | ||
| 312 | * @param string|integer $value | ||
| 313 | * @return bool | ||
| 314 | */ | ||
| 315 |     private function integer($value){ | ||
| 318 | |||
| 319 | /** | ||
| 320 | * check if value(s) is in a given array | ||
| 321 | * | ||
| 322 | * @param string|array $value | ||
| 323 | * @param array $arr | ||
| 324 | * @return bool | ||
| 325 | */ | ||
| 326 |     private function inArray($value, $arr){ | ||
| 338 | |||
| 339 | /** | ||
| 340 | * check if value is contains alphabetic characters and numbers | ||
| 341 | * | ||
| 342 | * @param mixed $value | ||
| 343 | * @return bool | ||
| 344 | */ | ||
| 345 |     private function alphaNum($value){ | ||
| 348 | |||
| 349 | /** | ||
| 350 | * check if value is contains alphabetic characters, numbers and spaces | ||
| 351 | * | ||
| 352 | * @param mixed $value | ||
| 353 | * @return bool | ||
| 354 | */ | ||
| 355 |     private function alphaNumWithSpaces($value){ | ||
| 358 | |||
| 359 | /** | ||
| 360 | * check if password has at least | ||
| 361 | * - one lowercase letter | ||
| 362 | * - one uppercase letter | ||
| 363 | * - one number | ||
| 364 | * - one special(non-word) character | ||
| 365 | * | ||
| 366 | * @param mixed $value | ||
| 367 | * @return bool | ||
| 368 | * @see http://stackoverflow.com/questions/8141125/regex-for-password-php | ||
| 369 | * @see http://code.runnable.com/UmrnTejI6Q4_AAIM/how-to-validate-complex-passwords-using-regular-expressions-for-php-and-pcre | ||
| 370 | */ | ||
| 371 |     private function password($value) { | ||
| 374 | |||
| 375 | /** | ||
| 376 | * check if value is equals to another value(strings) | ||
| 377 | * | ||
| 378 | * @param string $value | ||
| 379 | * @param array $args(value) | ||
| 380 | * @return bool | ||
| 381 | */ | ||
| 382 |     private function equals($value, $args){ | ||
| 385 | |||
| 386 | /** | ||
| 387 | * check if value is not equal to another value(strings) | ||
| 388 | * | ||
| 389 | * @param string $value | ||
| 390 | * @param array $args(value) | ||
| 391 | * @return bool | ||
| 392 | */ | ||
| 393 |     private function notEqual($value, $args){ | ||
| 396 | |||
| 397 | /** | ||
| 398 | * check if value is a valid email | ||
| 399 | * | ||
| 400 | * @param string $email | ||
| 401 | * @return bool | ||
| 402 | */ | ||
| 403 |     private function email($email){ | ||
| 406 | |||
| 407 | /** *********************************************** **/ | ||
| 408 | /** ************ Database Validations *********** **/ | ||
| 409 | /** *********************************************** **/ | ||
| 410 | |||
| 411 | /** | ||
| 412 | * check if a value of a column is unique. | ||
| 413 | * | ||
| 414 | * @param string $value | ||
| 415 | * @param array $args(table, column) | ||
| 416 | * @return bool | ||
| 417 | */ | ||
| 418 |     private function unique($value, $args){ | ||
| 431 | |||
| 432 | /** | ||
| 433 | * check if email is unique | ||
| 434 | * This will check if email exists and activated. | ||
| 435 | * | ||
| 436 | * @param string $email | ||
| 437 | * @return bool | ||
| 438 | */ | ||
| 439 |     private function emailUnique($email){ | ||
| 477 | |||
| 478 | /** *********************************************** **/ | ||
| 479 | /** ************ Login Validations *********** **/ | ||
| 480 | /** *********************************************** **/ | ||
| 481 | |||
| 482 | /** | ||
| 483 | * check if user credentials are valid or not. | ||
| 484 | * | ||
| 485 | * @param array $user | ||
| 486 | * @return bool | ||
| 487 | * @see Login::doLogin() | ||
| 488 | */ | ||
| 489 |     private function credentials($user){ | ||
| 495 | |||
| 496 | /** | ||
| 497 | * check if user has exceeded number of failed logins or number of forgotten password attempts. | ||
| 498 | * | ||
| 499 | * @param array $attempts | ||
| 500 | * @return bool | ||
| 501 | */ | ||
| 502 |     private function attempts($attempts){ | ||
| 528 | |||
| 529 | /** *********************************************** **/ | ||
| 530 | /** ************ File Validations *********** **/ | ||
| 531 | /** *********************************************** **/ | ||
| 532 | |||
| 533 | /** | ||
| 534 | * checks if file unique. | ||
| 535 | * | ||
| 536 | * @param array $path | ||
| 537 | * @return bool | ||
| 538 | * | ||
| 539 | * @see | ||
| 540 | */ | ||
| 541 |     private function fileUnique($path){ | ||
| 544 | |||
| 545 | /** | ||
| 546 | * checks for file errors | ||
| 547 | * | ||
| 548 | * @param array $file | ||
| 549 | * @return bool | ||
| 550 | */ | ||
| 551 |     private function fileErrors($file){ | ||
| 554 | |||
| 555 | /** | ||
| 556 | * checks if file uploaded successfully via HTTP POST | ||
| 557 | * | ||
| 558 | * @param array $file | ||
| 559 | * @return bool | ||
| 560 | * | ||
| 561 | * @see | ||
| 562 | */ | ||
| 563 |     private function fileUploaded($file){ | ||
| 566 | |||
| 567 | /** | ||
| 568 | * checks from file size | ||
| 569 | * | ||
| 570 | * @param array $file | ||
| 571 | * @param array $args(min,max) | ||
| 572 | * @return bool | ||
| 573 | */ | ||
| 574 |     private function fileSize($file, $args){ | ||
| 592 | |||
| 593 | /** | ||
| 594 | * checks from image size(dimensions) | ||
| 595 | * | ||
| 596 | * @param array $file | ||
| 597 | * @param array $dimensions(width,height) | ||
| 598 | * @return bool | ||
| 599 | */ | ||
| 600 |     private function imageSize($file, $dimensions){ | ||
| 615 | |||
| 616 | /** | ||
| 617 | * validate mime type | ||
| 618 | * | ||
| 619 | * @param array $file | ||
| 620 | * @param array $mimeTypes | ||
| 621 | * @throws Exception if finfo_open() doesn't exists | ||
| 622 | * @return bool | ||
| 623 | */ | ||
| 624 | View Code Duplication |     private function mimeType($file, $mimeTypes){ | |
| 642 | |||
| 643 | /** | ||
| 644 | * validate file extension returned from pathinfo() Vs mapped mime type to extension | ||
| 645 | * | ||
| 646 | * This reveal un desired errors in case of files with extension: zip, csv, ..etc | ||
| 647 | * | ||
| 648 | * @param array $file | ||
| 649 | * @param array $extension | ||
| 650 | * @return bool | ||
| 651 | */ | ||
| 652 |     private function fileExtension($file, $extension){ | ||
| 659 | |||
| 660 | /** *********************************************** **/ | ||
| 661 | /** ************ Default Messages *********** **/ | ||
| 662 | /** *********************************************** **/ | ||
| 663 | |||
| 664 | /** | ||
| 665 | * get default message for a rule | ||
| 666 | * | ||
| 667 | * Instead of passing your custom message every time, | ||
| 668 | * you can define a set of default messages. | ||
| 669 | * | ||
| 670 | * The pitfall of this method is, if you changed the validation method name, | ||
| 671 | * you need to change it here as well. | ||
| 672 | * | ||
| 673 | * @param string $rule | ||
| 674 | * @return mixed | ||
| 675 | */ | ||
| 676 |     private static function defaultMessages($rule){ | ||
| 705 | } | ||
| 706 | 
You can fix this by adding a namespace to your class:
When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries.