Complex classes like VirtualPage 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 VirtualPage, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
||
| 11 | class VirtualPage extends Page { |
||
| 12 | |||
| 13 | private static $description = 'Displays the content of another page'; |
||
| 14 | |||
| 15 | public static $virtualFields; |
||
| 16 | |||
| 17 | /** |
||
| 18 | * @var array Define fields that are not virtual - the virtual page must define these fields themselves. |
||
| 19 | * Note that anything in {@link self::config()->initially_copied_fields} is implicitly included in this list. |
||
| 20 | */ |
||
| 21 | private static $non_virtual_fields = array( |
||
| 22 | "ID", |
||
| 23 | "ClassName", |
||
| 24 | "ObsoleteClassName", |
||
| 25 | "SecurityTypeID", |
||
| 26 | "OwnerID", |
||
| 27 | "ParentID", |
||
| 28 | "URLSegment", |
||
| 29 | "Sort", |
||
| 30 | "Status", |
||
| 31 | 'ShowInMenus', |
||
| 32 | // 'Locale' |
||
| 33 | 'ShowInSearch', |
||
| 34 | 'Version', |
||
| 35 | "Embargo", |
||
| 36 | "Expiry", |
||
| 37 | "CanViewType", |
||
| 38 | "CanEditType", |
||
| 39 | "CopyContentFromID", |
||
| 40 | "HasBrokenLink", |
||
| 41 | ); |
||
| 42 | |||
| 43 | /** |
||
| 44 | * @var array Define fields that are initially copied to virtual pages but left modifiable after that. |
||
| 45 | */ |
||
| 46 | private static $initially_copied_fields = array( |
||
| 47 | 'ShowInMenus', |
||
| 48 | 'ShowInSearch', |
||
| 49 | 'URLSegment', |
||
| 50 | ); |
||
| 51 | |||
| 52 | private static $has_one = array( |
||
| 53 | "CopyContentFrom" => "SiteTree", |
||
| 54 | ); |
||
| 55 | |||
| 56 | private static $owns = array( |
||
| 57 | "CopyContentFrom", |
||
| 58 | ); |
||
| 59 | |||
| 60 | private static $db = array( |
||
| 61 | "VersionID" => "Int", |
||
| 62 | ); |
||
| 63 | |||
| 64 | /** |
||
| 65 | * Generates the array of fields required for the page type. |
||
| 66 | * |
||
| 67 | * @return array |
||
| 68 | */ |
||
| 69 | public function getVirtualFields() { |
||
| 70 | // Check if copied page exists |
||
| 71 | $record = $this->CopyContentFrom(); |
||
| 72 | if(!$record || !$record->exists()) { |
||
| 73 | return array(); |
||
| 74 | } |
||
| 75 | |||
| 76 | // Diff db with non-virtual fields |
||
| 77 | $fields = array_keys($record->db()); |
||
| 78 | $nonVirtualFields = $this->getNonVirtualisedFields(); |
||
| 79 | return array_diff($fields, $nonVirtualFields); |
||
| 80 | } |
||
| 81 | |||
| 82 | /** |
||
| 83 | * List of fields or properties to never virtualise |
||
| 84 | * |
||
| 85 | * @return array |
||
| 86 | */ |
||
| 87 | public function getNonVirtualisedFields() { |
||
| 88 | return array_merge($this->config()->non_virtual_fields, $this->config()->initially_copied_fields); |
||
| 89 | } |
||
| 90 | |||
| 91 | public function setCopyContentFromID($val) { |
||
| 92 | // Sanity check to prevent pages virtualising other virtual pages |
||
| 93 | if($val && DataObject::get_by_id('SiteTree', $val) instanceof VirtualPage) { |
||
| 94 | $val = 0; |
||
| 95 | } |
||
| 96 | return $this->setField("CopyContentFromID", $val); |
||
| 97 | } |
||
| 98 | |||
| 99 | public function ContentSource() { |
||
| 100 | $copied = $this->CopyContentFrom(); |
||
| 101 | if($copied && $copied->exists()) { |
||
| 102 | return $copied; |
||
| 103 | } |
||
| 104 | return $this; |
||
| 105 | } |
||
| 106 | |||
| 107 | /** |
||
| 108 | * For VirtualPage, add a canonical link tag linking to the original page |
||
| 109 | * See TRAC #6828 & http://support.google.com/webmasters/bin/answer.py?hl=en&answer=139394 |
||
| 110 | * |
||
| 111 | * @param boolean $includeTitle Show default <title>-tag, set to false for custom templating |
||
| 112 | * @return string The XHTML metatags |
||
| 113 | */ |
||
| 114 | public function MetaTags($includeTitle = true) { |
||
| 115 | $tags = parent::MetaTags($includeTitle); |
||
| 116 | $copied = $this->CopyContentFrom(); |
||
| 117 | if ($copied && $copied->exists()) { |
||
| 118 | $link = Convert::raw2att($copied->Link()); |
||
| 119 | $tags .= "<link rel=\"canonical\" href=\"{$link}\" />\n"; |
||
| 120 | } |
||
| 121 | return $tags; |
||
| 122 | } |
||
| 123 | |||
| 124 | public function allowedChildren() { |
||
| 125 | $copy = $this->CopyContentFrom(); |
||
| 126 | if($copy && $copy->exists()) { |
||
| 127 | return $copy->allowedChildren(); |
||
| 128 | } |
||
| 129 | return array(); |
||
| 130 | } |
||
| 131 | |||
| 132 | public function syncLinkTracking() { |
||
| 139 | |||
| 140 | /** |
||
| 141 | * We can only publish the page if there is a published source page |
||
| 142 | * |
||
| 143 | * @param Member $member Member to check |
||
| 144 | * @return bool |
||
| 145 | */ |
||
| 146 | public function canPublish($member = null) { |
||
| 149 | |||
| 150 | /** |
||
| 151 | * Returns true if is page is publishable by anyone at all |
||
| 152 | * Return false if the source page isn't published yet. |
||
| 153 | * |
||
| 154 | * Note that isPublishable doesn't affect ete from live, only publish. |
||
| 155 | */ |
||
| 156 | public function isPublishable() { |
||
| 170 | |||
| 171 | /** |
||
| 172 | * Generate the CMS fields from the fields from the original page. |
||
| 173 | */ |
||
| 174 | public function getCMSFields() { |
||
| 239 | |||
| 240 | public function onBeforeWrite() { |
||
| 241 | parent::onBeforeWrite(); |
||
| 242 | $this->refreshFromCopied(); |
||
| 243 | } |
||
| 244 | |||
| 245 | /** |
||
| 246 | * Copy any fields from the copied record to bootstrap /backup |
||
| 247 | */ |
||
| 248 | protected function refreshFromCopied() { |
||
| 268 | |||
| 269 | public function getSettingsFields() { |
||
| 288 | |||
| 289 | public function validate() { |
||
| 290 | $result = parent::validate(); |
||
| 291 | |||
| 292 | // "Can be root" validation |
||
| 293 | $orig = $this->CopyContentFrom(); |
||
| 294 | if($orig && $orig->exists() && !$orig->stat('can_be_root') && !$this->ParentID) { |
||
| 295 | $result->error( |
||
| 296 | _t( |
||
| 297 | 'VirtualPage.PageTypNotAllowedOnRoot', |
||
| 298 | 'Original page type "{type}" is not allowed on the root level for this virtual page', |
||
| 299 | array('type' => $orig->i18n_singular_name()) |
||
| 300 | ), |
||
| 301 | 'CAN_BE_ROOT_VIRTUAL' |
||
| 302 | ); |
||
| 303 | } |
||
| 304 | |||
| 305 | return $result; |
||
| 306 | } |
||
| 307 | |||
| 308 | public function updateImageTracking() { |
||
| 318 | |||
| 319 | /** |
||
| 320 | * @param string $numChildrenMethod |
||
| 321 | * @return string |
||
| 322 | */ |
||
| 323 | public function CMSTreeClasses($numChildrenMethod="numChildren") { |
||
| 326 | |||
| 327 | /** |
||
| 328 | * Allow attributes on the master page to pass |
||
| 329 | * through to the virtual page |
||
| 330 | * |
||
| 331 | * @param string $field |
||
| 332 | * @return mixed |
||
| 333 | */ |
||
| 334 | public function __get($field) { |
||
| 343 | |||
| 344 | public function getField($field) { |
||
| 350 | |||
| 351 | /** |
||
| 352 | * Check if given field is virtualised |
||
| 353 | * |
||
| 354 | * @param string $field |
||
| 355 | * @return bool |
||
| 356 | */ |
||
| 357 | public function isFieldVirtualised($field) { |
||
| 373 | |||
| 374 | /** |
||
| 375 | * Pass unrecognized method calls on to the original data object |
||
| 376 | * |
||
| 377 | * @param string $method |
||
| 378 | * @param string $args |
||
| 379 | * @return mixed |
||
| 380 | */ |
||
| 381 | public function __call($method, $args) { |
||
| 388 | |||
| 389 | /** |
||
| 390 | * @param string $field |
||
| 391 | * @return bool |
||
| 392 | */ |
||
| 393 | public function hasField($field) { |
||
| 394 | if(parent::hasField($field)) { |
||
| 395 | return true; |
||
| 396 | } |
||
| 397 | $copy = $this->CopyContentFrom(); |
||
| 398 | return $copy && $copy->exists() && $copy->hasField($field); |
||
| 399 | } |
||
| 400 | |||
| 401 | /** |
||
| 402 | * Overwrite to also check for method on the original data object |
||
| 403 | * |
||
| 404 | * @param string $method |
||
| 405 | * @return bool |
||
| 406 | */ |
||
| 407 | public function hasMethod($method) { |
||
| 418 | |||
| 419 | /** |
||
| 420 | * Return the "casting helper" (a piece of PHP code that when evaluated creates a casted value object) for a field |
||
| 421 | * on this object. |
||
| 422 | * |
||
| 423 | * @param string $field |
||
| 424 | * @return string |
||
| 425 | */ |
||
| 426 | public function castingHelper($field) { |
||
| 433 | |||
| 434 | } |
||
| 435 | |||
| 436 | /** |
||
| 515 |
It seems like the type of the argument is not accepted by the function/method which you are calling.
In some cases, in particular if PHP’s automatic type-juggling kicks in this might be fine. In other cases, however this might be a bug.
We suggest to add an explicit type cast like in the following example: