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 AbstractAuthenticator 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 AbstractAuthenticator, and based on these observations, apply Extract Interface, too.
| 1 | <?php | ||
| 34 | abstract class AbstractAuthenticator implements | ||
| 35 | AuthenticatorInterface, | ||
| 36 | LoggerAwareInterface | ||
| 37 | { | ||
| 38 | use LoggerAwareTrait; | ||
| 39 | |||
| 40 | const AUTH_BY_PASSWORD = 'password'; | ||
| 41 | const AUTH_BY_SESSION = 'session'; | ||
| 42 | const AUTH_BY_TOKEN = 'token'; | ||
| 43 | |||
| 44 | /** | ||
| 45 | * The user that was last authenticated. | ||
| 46 | * | ||
| 47 | * @var AuthenticatableInterface | ||
| 48 | */ | ||
| 49 | private $authenticatedUser; | ||
| 50 | |||
| 51 | /** | ||
| 52 | * The token that was last authenticated. | ||
| 53 | * | ||
| 54 | * @var \Charcoal\User\AuthTokenInterface | ||
| 55 | */ | ||
| 56 | private $authenticatedToken; | ||
| 57 | |||
| 58 | /** | ||
| 59 | * The authentication method of the user that was last authenticated. | ||
| 60 | * | ||
| 61 | * @var string | ||
| 62 | */ | ||
| 63 | private $authenticatedMethod; | ||
| 64 | |||
| 65 | /** | ||
| 66 | * Indicates if the logout method has been called. | ||
| 67 | * | ||
| 68 | * @var boolean | ||
| 69 | */ | ||
| 70 | private $isLoggedOut = false; | ||
| 71 | |||
| 72 | /** | ||
| 73 | * The user object type. | ||
| 74 | * | ||
| 75 | * @var string | ||
| 76 | */ | ||
| 77 | private $userType; | ||
| 78 | |||
| 79 | /** | ||
| 80 | * Store the user model factory instance for the current class. | ||
| 81 | * | ||
| 82 | * @var FactoryInterface | ||
| 83 | */ | ||
| 84 | private $userFactory; | ||
| 85 | |||
| 86 | /** | ||
| 87 | * The auth-token object type. | ||
| 88 | * | ||
| 89 | * @var string | ||
| 90 | */ | ||
| 91 | private $tokenType; | ||
| 92 | |||
| 93 | /** | ||
| 94 | * Store the auth-token model factory instance for the current class. | ||
| 95 | * | ||
| 96 | * @var FactoryInterface | ||
| 97 | */ | ||
| 98 | private $tokenFactory; | ||
| 99 | |||
| 100 | /** | ||
| 101 | * @param array $data Class dependencies. | ||
| 102 | */ | ||
| 103 | public function __construct(array $data) | ||
| 111 | |||
| 112 | /** | ||
| 113 | * Retrieve the user object type. | ||
| 114 | * | ||
| 115 | * @return string | ||
| 116 | */ | ||
| 117 | public function userType() | ||
| 121 | |||
| 122 | /** | ||
| 123 | * Retrieve the user model factory. | ||
| 124 | * | ||
| 125 | * @throws RuntimeException If the model factory was not previously set. | ||
| 126 | * @return FactoryInterface | ||
| 127 | */ | ||
| 128 | public function userFactory() | ||
| 132 | |||
| 133 | /** | ||
| 134 | * Create a new user model. | ||
| 135 | * | ||
| 136 | * @return \Charcoal\User\Access\AuthenticatableInterface | ||
| 137 | */ | ||
| 138 | public function createUser() | ||
| 142 | |||
| 143 | /** | ||
| 144 | * Retrieve the auth-token object type. | ||
| 145 | * | ||
| 146 | * @return string | ||
| 147 | */ | ||
| 148 | public function tokenType() | ||
| 152 | |||
| 153 | /** | ||
| 154 | * Retrieve the auth-token model factory. | ||
| 155 | * | ||
| 156 | * @throws RuntimeException If the token factory was not previously set. | ||
| 157 | * @return FactoryInterface | ||
| 158 | */ | ||
| 159 | public function tokenFactory() | ||
| 163 | |||
| 164 | /** | ||
| 165 | * Create a new auth-token model. | ||
| 166 | * | ||
| 167 | * @return \Charcoal\User\AuthTokenInterface | ||
| 168 | */ | ||
| 169 | public function createToken() | ||
| 173 | |||
| 174 | /** | ||
| 175 | * Set the user object type (model). | ||
| 176 | * | ||
| 177 | * @param string $type The user object type. | ||
| 178 | * @throws InvalidArgumentException If the user object type parameter is not a string. | ||
| 179 | * @return void | ||
| 180 | */ | ||
| 181 | protected function setUserType($type) | ||
| 191 | |||
| 192 | /** | ||
| 193 | * Set a user model factory. | ||
| 194 | * | ||
| 195 | * @param FactoryInterface $factory The factory used to create new user instances. | ||
| 196 | * @return void | ||
| 197 | */ | ||
| 198 | protected function setUserFactory(FactoryInterface $factory) | ||
| 202 | |||
| 203 | /** | ||
| 204 | * Set the authorization token type (model). | ||
| 205 | * | ||
| 206 | * @param string $type The auth-token object type. | ||
| 207 | * @throws InvalidArgumentException If the token object type parameter is not a string. | ||
| 208 | * @return void | ||
| 209 | */ | ||
| 210 | protected function setTokenType($type) | ||
| 220 | |||
| 221 | /** | ||
| 222 | * Set a model factory for token-based authentication. | ||
| 223 | * | ||
| 224 | * @param FactoryInterface $factory The factory used to create new auth-token instances. | ||
| 225 | * @return void | ||
| 226 | */ | ||
| 227 | protected function setTokenFactory(FactoryInterface $factory) | ||
| 231 | |||
| 232 | /** | ||
| 233 | * Retrieve the currently authenticated user. | ||
| 234 | * | ||
| 235 | * The method will attempt to authenticate a user. | ||
| 236 | * | ||
| 237 | * @return AuthenticatableInterface|null | ||
| 238 | */ | ||
| 239 | public function user() | ||
| 251 | |||
| 252 | /** | ||
| 253 | * Retrieve the ID for the currently authenticated user. | ||
| 254 | * | ||
| 255 | * The method will attempt to authenticate a user. | ||
| 256 | * | ||
| 257 | * @return mixed | ||
| 258 | */ | ||
| 259 | public function userId() | ||
| 272 | |||
| 273 | /** | ||
| 274 | * Retrieve the currently cached user. | ||
| 275 | * | ||
| 276 | * @return AuthenticatableInterface|null | ||
| 277 | */ | ||
| 278 | public function getUser() | ||
| 282 | |||
| 283 | /** | ||
| 284 | * Retrieve the ID for the currently cached user. | ||
| 285 | * | ||
| 286 | * @return mixed | ||
| 287 | */ | ||
| 288 | public function getUserId() | ||
| 297 | |||
| 298 | /** | ||
| 299 | * Set the authenticated user. | ||
| 300 | * | ||
| 301 | * @param AuthenticatableInterface $user The authenticated user. | ||
| 302 | * @return void | ||
| 303 | */ | ||
| 304 | public function setUser(AuthenticatableInterface $user) | ||
| 309 | |||
| 310 | /** | ||
| 311 | * Determine if the current user is authenticated. | ||
| 312 | * | ||
| 313 | * @return boolean | ||
| 314 | */ | ||
| 315 | public function check() | ||
| 319 | |||
| 320 | /** | ||
| 321 | * Determines if the logout method has been called. | ||
| 322 | * | ||
| 323 | * @return boolean TRUE if the logout method has been called, FALSE otherwise. | ||
| 324 | */ | ||
| 325 | protected function isLoggedOut() | ||
| 329 | |||
| 330 | /** | ||
| 331 | * Retrieve the authentication method of the current user. | ||
| 332 | * | ||
| 333 | * If the current user is authenticated, one of the | ||
| 334 | * `self::AUTH_BY_*` constants is returned. | ||
| 335 | * | ||
| 336 | * @return string|null | ||
| 337 | */ | ||
| 338 | public function getAuthenticationMethod() | ||
| 342 | |||
| 343 | /** | ||
| 344 | * Retrieve the authentication token of the current user. | ||
| 345 | * | ||
| 346 | * If the current user was authenticated by token, | ||
| 347 | * the auth token instance is returned. | ||
| 348 | * | ||
| 349 | * @return AuthTokenInterface|null | ||
| 350 | */ | ||
| 351 | public function getAuthenticationToken() | ||
| 355 | |||
| 356 | /** | ||
| 357 | * Log a user into the application. | ||
| 358 | * | ||
| 359 | * @param AuthenticatableInterface $user The authenticated user to log in. | ||
| 360 | * @param boolean $remember Whether to "remember" the user or not. | ||
| 361 | * @return void | ||
| 362 | */ | ||
| 363 | public function login(AuthenticatableInterface $user, $remember = false) | ||
| 377 | |||
| 378 | /** | ||
| 379 | * Log the user out of the application. | ||
| 380 | * | ||
| 381 | * @return void | ||
| 382 | */ | ||
| 383 | public function logout() | ||
| 392 | |||
| 393 | /** | ||
| 394 | * Attempt to authenticate a user by session or token. | ||
| 395 | * | ||
| 396 | * The user is authenticated via _session ID_ or _auth token_. | ||
| 397 | * | ||
| 398 | * @return AuthenticatableInterface|null Returns the authenticated user object | ||
| 399 | * or NULL if not authenticated. | ||
| 400 | */ | ||
| 401 | public function authenticate() | ||
| 423 | |||
| 424 | /** | ||
| 425 | * Attempt to authenticate a user using the given credentials. | ||
| 426 | * | ||
| 427 | * @param string $identifier The login ID, part of necessary credentials. | ||
| 428 | * @param string $password The password, part of necessary credentials. | ||
| 429 | * @throws InvalidArgumentException If the credentials are invalid or missing. | ||
| 430 | * @return AuthenticatableInterface|null Returns the authenticated user object | ||
| 431 | * or NULL if not authenticated. | ||
| 432 | */ | ||
| 433 | public function authenticateByPassword($identifier, $password) | ||
| 479 | |||
| 480 | /** | ||
| 481 | * Attempt to authenticate a user using their session ID. | ||
| 482 | * | ||
| 483 | * @return AuthenticatableInterface|null Returns the authenticated user object | ||
| 484 | * or NULL if not authenticated. | ||
| 485 | */ | ||
| 486 | protected function authenticateBySession() | ||
| 514 | |||
| 515 | /** | ||
| 516 | * Attempt to authenticate a user using their auth token. | ||
| 517 | * | ||
| 518 | * @return AuthenticatableInterface|null Returns the authenticated user object | ||
| 519 | * or NULL if not authenticated. | ||
| 520 | */ | ||
| 521 | protected function authenticateByToken() | ||
| 559 | |||
| 560 | /** | ||
| 561 | * Delete the user data from the session. | ||
| 562 | * | ||
| 563 | * @param AuthenticatableInterface|null $user The authenticated user to forget. | ||
| 564 | * @return void | ||
| 565 | */ | ||
| 566 | protected function deleteUserSession(AuthenticatableInterface $user = null) | ||
| 577 | |||
| 578 | /** | ||
| 579 | * Delete the user data from the cookie. | ||
| 580 | * | ||
| 581 | * @param AuthenticatableInterface|null $user The authenticated user to forget. | ||
| 582 | * @return void | ||
| 583 | */ | ||
| 584 | protected function deleteUserTokens(AuthenticatableInterface $user = null) | ||
| 605 | |||
| 606 | /** | ||
| 607 | * Delete the user data from the cookie. | ||
| 608 | * | ||
| 609 | * @throws InvalidArgumentException If trying to save a user to cookies without an ID. | ||
| 610 | * @return void | ||
| 611 | */ | ||
| 612 | protected function deleteCurrentToken() | ||
| 628 | |||
| 629 | /** | ||
| 630 | * Update the session with the given user. | ||
| 631 | * | ||
| 632 | * @param AuthenticatableInterface $user The authenticated user to remember. | ||
| 633 | * @throws InvalidArgumentException If trying to save a user to session without an ID. | ||
| 634 | * @return void | ||
| 635 | */ | ||
| 636 | protected function updateUserSession(AuthenticatableInterface $user) | ||
| 647 | |||
| 648 | /** | ||
| 649 | * Store the auth token for the given user in a cookie. | ||
| 650 | * | ||
| 651 | * @param AuthenticatableInterface $user The authenticated user to remember. | ||
| 652 | * @throws InvalidArgumentException If trying to save a user to cookies without an ID. | ||
| 653 | * @return void | ||
| 654 | */ | ||
| 655 | protected function updateCurrentToken(AuthenticatableInterface $user) | ||
| 676 | |||
| 677 | /** | ||
| 678 | * Validate the user login credentials are acceptable. | ||
| 679 | * | ||
| 680 | * @param string $identifier The user identifier to check. | ||
| 681 | * @param string $password The user password to check. | ||
| 682 | * @return boolean Returns TRUE if the credentials are acceptable, or FALSE otherwise. | ||
| 683 | */ | ||
| 684 | public function validateLogin($identifier, $password) | ||
| 688 | |||
| 689 | /** | ||
| 690 | * Validate the user identifier is acceptable. | ||
| 691 | * | ||
| 692 | * @param string $identifier The login ID. | ||
| 693 | * @return boolean Returns TRUE if the identifier is acceptable, or FALSE otherwise. | ||
| 694 | */ | ||
| 695 | public function validateAuthIdentifier($identifier) | ||
| 699 | |||
| 700 | /** | ||
| 701 | * Validate the user password is acceptable. | ||
| 702 | * | ||
| 703 | * @param string $password The password. | ||
| 704 | * @return boolean Returns TRUE if the password is acceptable, or FALSE otherwise. | ||
| 705 | */ | ||
| 706 | public function validateAuthPassword($password) | ||
| 710 | |||
| 711 | /** | ||
| 712 | * Validate the user authentication state is okay. | ||
| 713 | * | ||
| 714 | * For example, inactive users can not authenticate. | ||
| 715 | * | ||
| 716 | * @param AuthenticatableInterface $user The user to validate. | ||
| 717 | * @return boolean | ||
| 718 | */ | ||
| 719 | public function validateAuthentication(AuthenticatableInterface $user) | ||
| 723 | |||
| 724 | /** | ||
| 725 | * Updates the user's password hash. | ||
| 726 | * | ||
| 727 | * Assumes that the existing hash needs to be rehashed. | ||
| 728 | * | ||
| 729 | * @param AuthenticatableInterface $user The user to update. | ||
| 730 | * @param string $password The plain-text password to hash. | ||
| 731 | * @param boolean $update Whether to persist changes to storage. | ||
| 732 | * @throws InvalidArgumentException If the password is invalid. | ||
| 733 | * @return boolean Returns TRUE if the password was changed, or FALSE otherwise. | ||
| 734 | */ | ||
| 735 | View Code Duplication | protected function rehashUserPassword(AuthenticatableInterface $user, $password, $update = true) | |
| 783 | |||
| 784 | /** | ||
| 785 | * Updates the user's password hash. | ||
| 786 | * | ||
| 787 | * @param AuthenticatableInterface $user The user to update. | ||
| 788 | * @param string $password The plain-text password to hash. | ||
| 789 | * @param boolean $update Whether to persist changes to storage. | ||
| 790 | * @throws InvalidArgumentException If the password is invalid. | ||
| 791 | * @return boolean Returns TRUE if the password was changed, or FALSE otherwise. | ||
| 792 | */ | ||
| 793 | View Code Duplication | protected function changeUserPassword(AuthenticatableInterface $user, $password, $update = true) | |
| 841 | |||
| 842 | /** | ||
| 843 | * Clear the authenticator's internal cache. | ||
| 844 | * | ||
| 845 | * @return void | ||
| 846 | */ | ||
| 847 | protected function clearAuthenticator() | ||
| 854 | } | ||
| 855 | 
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the interface: