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 AssetAdmin 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 AssetAdmin, and based on these observations, apply Extract Interface, too.
| 1 | <?php  | 
            ||
| 47 | class AssetAdmin extends LeftAndMain implements PermissionProvider  | 
            ||
| 48 | { | 
            ||
| 49 | private static $url_segment = 'assets';  | 
            ||
| 50 | |||
| 51 | private static $url_rule = '/$Action/$ID';  | 
            ||
| 52 | |||
| 53 | private static $menu_title = 'Files';  | 
            ||
| 54 | |||
| 55 | private static $menu_icon_class = 'font-icon-image';  | 
            ||
| 56 | |||
| 57 | private static $tree_class = Folder::class;  | 
            ||
| 58 | |||
| 59 | private static $url_handlers = [  | 
            ||
| 60 | // Legacy redirect for SS3-style detail view  | 
            ||
| 61 | 'EditForm/field/File/item/$FileID/$Action' => 'legacyRedirectForEditView',  | 
            ||
| 62 | // Pass all URLs to the index, for React to unpack  | 
            ||
| 63 | 'show/$FolderID/edit/$FileID' => 'index',  | 
            ||
| 64 | // API access points with structured data  | 
            ||
| 65 | 'POST api/createFile' => 'apiCreateFile',  | 
            ||
| 66 | 'POST api/uploadFile' => 'apiUploadFile',  | 
            ||
| 67 | 'GET api/history' => 'apiHistory',  | 
            ||
| 68 | 'fileEditForm/$ID' => 'fileEditForm',  | 
            ||
| 69 | 'fileInsertForm/$ID' => 'fileInsertForm',  | 
            ||
| 70 | 'fileEditorLinkForm/$ID' => 'fileEditorLinkForm',  | 
            ||
| 71 | 'fileHistoryForm/$ID/$VersionID' => 'fileHistoryForm',  | 
            ||
| 72 | 'folderCreateForm/$ParentID' => 'folderCreateForm',  | 
            ||
| 73 | ];  | 
            ||
| 74 | |||
| 75 | /**  | 
            ||
| 76 | * Amount of results showing on a single page.  | 
            ||
| 77 | *  | 
            ||
| 78 | * @config  | 
            ||
| 79 | * @var int  | 
            ||
| 80 | */  | 
            ||
| 81 | private static $page_length = 50;  | 
            ||
| 82 | |||
| 83 | /**  | 
            ||
| 84 | * @config  | 
            ||
| 85 | * @see Upload->allowedMaxFileSize  | 
            ||
| 86 | * @var int  | 
            ||
| 87 | */  | 
            ||
| 88 | private static $allowed_max_file_size;  | 
            ||
| 89 | |||
| 90 | /**  | 
            ||
| 91 | * @config  | 
            ||
| 92 | *  | 
            ||
| 93 | * @var int  | 
            ||
| 94 | */  | 
            ||
| 95 | private static $max_history_entries = 100;  | 
            ||
| 96 | |||
| 97 | /**  | 
            ||
| 98 | * @var array  | 
            ||
| 99 | */  | 
            ||
| 100 | private static $allowed_actions = array(  | 
            ||
| 101 | 'legacyRedirectForEditView',  | 
            ||
| 102 | 'apiCreateFile',  | 
            ||
| 103 | 'apiUploadFile',  | 
            ||
| 104 | 'apiHistory',  | 
            ||
| 105 | 'folderCreateForm',  | 
            ||
| 106 | 'fileEditForm',  | 
            ||
| 107 | 'fileHistoryForm',  | 
            ||
| 108 | 'addToCampaignForm',  | 
            ||
| 109 | 'fileInsertForm',  | 
            ||
| 110 | 'fileEditorLinkForm',  | 
            ||
| 111 | 'schema',  | 
            ||
| 112 | 'fileSelectForm',  | 
            ||
| 113 | 'fileSearchForm',  | 
            ||
| 114 | );  | 
            ||
| 115 | |||
| 116 | private static $required_permission_codes = 'CMS_ACCESS_AssetAdmin';  | 
            ||
| 117 | |||
| 118 | /**  | 
            ||
| 119 | * Retina thumbnail image (native size: 176)  | 
            ||
| 120 | *  | 
            ||
| 121 | * @config  | 
            ||
| 122 | * @var int  | 
            ||
| 123 | */  | 
            ||
| 124 | private static $thumbnail_width = 352;  | 
            ||
| 125 | |||
| 126 | /**  | 
            ||
| 127 | * Retina thumbnail height (native size: 132)  | 
            ||
| 128 | *  | 
            ||
| 129 | * @config  | 
            ||
| 130 | * @var int  | 
            ||
| 131 | */  | 
            ||
| 132 | private static $thumbnail_height = 264;  | 
            ||
| 133 | |||
| 134 | /**  | 
            ||
| 135 | * Safely limit max inline thumbnail size to 200kb  | 
            ||
| 136 | *  | 
            ||
| 137 | * @config  | 
            ||
| 138 | * @var int  | 
            ||
| 139 | */  | 
            ||
| 140 | private static $max_thumbnail_bytes = 200000;  | 
            ||
| 141 | |||
| 142 | /**  | 
            ||
| 143 | * Set up the controller  | 
            ||
| 144 | */  | 
            ||
| 145 | public function init()  | 
            ||
| 146 |     { | 
            ||
| 147 | parent::init();  | 
            ||
| 148 | |||
| 149 |         $module = ModuleLoader::getModule('silverstripe/asset-admin'); | 
            ||
| 150 |         Requirements::add_i18n_javascript($module->getResourcePath('client/lang'), false, true); | 
            ||
| 151 |         Requirements::javascript($module->getResourcePath("client/dist/js/bundle.js")); | 
            ||
| 152 |         Requirements::css($module->getResourcePath("client/dist/styles/bundle.css")); | 
            ||
| 153 | |||
| 154 |         CMSBatchActionHandler::register('delete', DeleteAssets::class, Folder::class); | 
            ||
| 155 | }  | 
            ||
| 156 | |||
| 157 | public function getClientConfig()  | 
            ||
| 158 |     { | 
            ||
| 159 | $baseLink = $this->Link();  | 
            ||
| 160 | return array_merge(parent::getClientConfig(), [  | 
            ||
| 161 | 'reactRouter' => true,  | 
            ||
| 162 | 'createFileEndpoint' => [  | 
            ||
| 163 | 'url' => Controller::join_links($baseLink, 'api/createFile'),  | 
            ||
| 164 | 'method' => 'post',  | 
            ||
| 165 | 'payloadFormat' => 'urlencoded',  | 
            ||
| 166 | ],  | 
            ||
| 167 | 'uploadFileEndpoint' => [  | 
            ||
| 168 | 'url' => Controller::join_links($baseLink, 'api/uploadFile'),  | 
            ||
| 169 | 'method' => 'post',  | 
            ||
| 170 | 'payloadFormat' => 'urlencoded',  | 
            ||
| 171 | ],  | 
            ||
| 172 | 'historyEndpoint' => [  | 
            ||
| 173 | 'url' => Controller::join_links($baseLink, 'api/history'),  | 
            ||
| 174 | 'method' => 'get',  | 
            ||
| 175 | 'responseFormat' => 'json',  | 
            ||
| 176 | ],  | 
            ||
| 177 | 'limit' => $this->config()->page_length,  | 
            ||
| 178 | 'form' => [  | 
            ||
| 179 | 'fileEditForm' => [  | 
            ||
| 180 |                     'schemaUrl' => $this->Link('schema/fileEditForm') | 
            ||
| 181 | ],  | 
            ||
| 182 | 'fileInsertForm' => [  | 
            ||
| 183 |                     'schemaUrl' => $this->Link('schema/fileInsertForm') | 
            ||
| 184 | ],  | 
            ||
| 185 | 'remoteEditForm' => [  | 
            ||
| 186 | 'schemaUrl' => LeftAndMain::singleton()  | 
            ||
| 187 |                         ->Link('Modals/remoteEditFormSchema'), | 
            ||
| 188 | ],  | 
            ||
| 189 | 'remoteCreateForm' => [  | 
            ||
| 190 | 'schemaUrl' => LeftAndMain::singleton()  | 
            ||
| 191 |                         ->Link('methodSchema/Modals/remoteCreateForm') | 
            ||
| 192 | ],  | 
            ||
| 193 | 'fileSelectForm' => [  | 
            ||
| 194 |                     'schemaUrl' => $this->Link('schema/fileSelectForm') | 
            ||
| 195 | ],  | 
            ||
| 196 | 'addToCampaignForm' => [  | 
            ||
| 197 |                     'schemaUrl' => $this->Link('schema/addToCampaignForm') | 
            ||
| 198 | ],  | 
            ||
| 199 | 'fileHistoryForm' => [  | 
            ||
| 200 |                     'schemaUrl' => $this->Link('schema/fileHistoryForm') | 
            ||
| 201 | ],  | 
            ||
| 202 | 'fileSearchForm' => [  | 
            ||
| 203 |                     'schemaUrl' => $this->Link('schema/fileSearchForm') | 
            ||
| 204 | ],  | 
            ||
| 205 | 'folderCreateForm' => [  | 
            ||
| 206 |                     'schemaUrl' => $this->Link('schema/folderCreateForm') | 
            ||
| 207 | ],  | 
            ||
| 208 | 'fileEditorLinkForm' => [  | 
            ||
| 209 |                     'schemaUrl' => $this->Link('schema/fileEditorLinkForm'), | 
            ||
| 210 | ],  | 
            ||
| 211 | ],  | 
            ||
| 212 | ]);  | 
            ||
| 213 | }  | 
            ||
| 214 | |||
| 215 | /**  | 
            ||
| 216 | * Creates a single file based on a form-urlencoded upload.  | 
            ||
| 217 | *  | 
            ||
| 218 | * @param HTTPRequest $request  | 
            ||
| 219 | * @return HTTPRequest|HTTPResponse  | 
            ||
| 220 | */  | 
            ||
| 221 | public function apiCreateFile(HTTPRequest $request)  | 
            ||
| 301 | |||
| 302 | /**  | 
            ||
| 303 | * Upload a new asset for a pre-existing record. Returns the asset tuple.  | 
            ||
| 304 | *  | 
            ||
| 305 | * Note that conflict resolution is as follows:  | 
            ||
| 306 | * - If uploading a file with the same extension, we simply keep the same filename,  | 
            ||
| 307 | * and overwrite any existing files (same name + sha = don't duplicate).  | 
            ||
| 308 | * - If uploading a new file with a different extension, then the filename will  | 
            ||
| 309 | * be replaced, and will be checked for uniqueness against other File dataobjects.  | 
            ||
| 310 | *  | 
            ||
| 311 | * @param HTTPRequest $request Request containing vars 'ID' of parent record ID,  | 
            ||
| 312 | * and 'Name' as form filename value  | 
            ||
| 313 | * @return HTTPRequest|HTTPResponse  | 
            ||
| 314 | */  | 
            ||
| 315 | public function apiUploadFile(HTTPRequest $request)  | 
            ||
| 396 | |||
| 397 | /**  | 
            ||
| 398 | * Returns a JSON array for history of a given file ID. Returns a list of all the history.  | 
            ||
| 399 | *  | 
            ||
| 400 | * @param HTTPRequest $request  | 
            ||
| 401 | * @return HTTPResponse  | 
            ||
| 402 | */  | 
            ||
| 403 | public function apiHistory(HTTPRequest $request)  | 
            ||
| 491 | |||
| 492 | /**  | 
            ||
| 493 | * Redirects 3.x style detail links to new 4.x style routing.  | 
            ||
| 494 | *  | 
            ||
| 495 | * @param HTTPRequest $request  | 
            ||
| 496 | */  | 
            ||
| 497 | public function legacyRedirectForEditView($request)  | 
            ||
| 505 | |||
| 506 | /**  | 
            ||
| 507 | * Given a file return the CMS link to edit it  | 
            ||
| 508 | *  | 
            ||
| 509 | * @param File $file  | 
            ||
| 510 | * @return string  | 
            ||
| 511 | */  | 
            ||
| 512 | public function getFileEditLink($file)  | 
            ||
| 525 | |||
| 526 | /**  | 
            ||
| 527 | * Get an asset renamer for the given filename.  | 
            ||
| 528 | *  | 
            ||
| 529 | * @param string $filename Path name  | 
            ||
| 530 | * @return AssetNameGenerator  | 
            ||
| 531 | */  | 
            ||
| 532 | protected function getNameGenerator($filename)  | 
            ||
| 537 | |||
| 538 | /**  | 
            ||
| 539 | * @todo Implement on client  | 
            ||
| 540 | *  | 
            ||
| 541 | * @param bool $unlinked  | 
            ||
| 542 | * @return ArrayList  | 
            ||
| 543 | */  | 
            ||
| 544 | public function breadcrumbs($unlinked = false)  | 
            ||
| 548 | |||
| 549 | |||
| 550 | /**  | 
            ||
| 551 | * Don't include class namespace in auto-generated CSS class  | 
            ||
| 552 | */  | 
            ||
| 553 | public function baseCSSClasses()  | 
            ||
| 557 | |||
| 558 | public function providePermissions()  | 
            ||
| 569 | |||
| 570 | /**  | 
            ||
| 571 | * Build a form scaffolder for this model  | 
            ||
| 572 | *  | 
            ||
| 573 |      * NOTE: Volatile api. May be moved to {@see LeftAndMain} | 
            ||
| 574 | *  | 
            ||
| 575 | * @param File $file  | 
            ||
| 576 | * @return FormFactory  | 
            ||
| 577 | */  | 
            ||
| 578 | public function getFormFactory(File $file)  | 
            ||
| 591 | |||
| 592 | /**  | 
            ||
| 593 | * The form is used to generate a form schema,  | 
            ||
| 594 | * as well as an intermediary object to process data through API endpoints.  | 
            ||
| 595 | * Since it's used directly on API endpoints, it does not have any form actions.  | 
            ||
| 596 |      * It handles both {@link File} and {@link Folder} records. | 
            ||
| 597 | *  | 
            ||
| 598 | * @param int $id  | 
            ||
| 599 | * @return Form  | 
            ||
| 600 | */  | 
            ||
| 601 | public function getFileEditForm($id)  | 
            ||
| 605 | |||
| 606 | /**  | 
            ||
| 607 | * Get file edit form  | 
            ||
| 608 | *  | 
            ||
| 609 | * @param HTTPRequest $request  | 
            ||
| 610 | * @return Form  | 
            ||
| 611 | */  | 
            ||
| 612 | View Code Duplication | public function fileEditForm($request = null)  | 
            |
| 626 | |||
| 627 | /**  | 
            ||
| 628 | * The form is used to generate a form schema,  | 
            ||
| 629 | * as well as an intermediary object to process data through API endpoints.  | 
            ||
| 630 | * Since it's used directly on API endpoints, it does not have any form actions.  | 
            ||
| 631 |      * It handles both {@link File} and {@link Folder} records. | 
            ||
| 632 | *  | 
            ||
| 633 | * @param int $id  | 
            ||
| 634 | * @return Form  | 
            ||
| 635 | */  | 
            ||
| 636 | public function getFileInsertForm($id)  | 
            ||
| 640 | |||
| 641 | /**  | 
            ||
| 642 | * Get file insert media form  | 
            ||
| 643 | *  | 
            ||
| 644 | * @param HTTPRequest $request  | 
            ||
| 645 | * @return Form  | 
            ||
| 646 | */  | 
            ||
| 647 | View Code Duplication | public function fileInsertForm($request = null)  | 
            |
| 661 | |||
| 662 | /**  | 
            ||
| 663 | * The form used to generate a form schema, since it's used directly on API endpoints,  | 
            ||
| 664 | * it does not have any form actions.  | 
            ||
| 665 | *  | 
            ||
| 666 | * @param $id  | 
            ||
| 667 | * @return Form  | 
            ||
| 668 | */  | 
            ||
| 669 | public function getFileEditorLinkForm($id)  | 
            ||
| 673 | |||
| 674 | /**  | 
            ||
| 675 | * Get the file insert link form  | 
            ||
| 676 | *  | 
            ||
| 677 | * @param HTTPRequest $request  | 
            ||
| 678 | * @return Form  | 
            ||
| 679 | */  | 
            ||
| 680 | View Code Duplication | public function fileEditorLinkForm($request = null)  | 
            |
| 694 | |||
| 695 | /**  | 
            ||
| 696 | * Abstract method for generating a form for a file  | 
            ||
| 697 | *  | 
            ||
| 698 | * @param int $id Record ID  | 
            ||
| 699 | * @param string $name Form name  | 
            ||
| 700 | * @param array $context Form context  | 
            ||
| 701 | * @return Form  | 
            ||
| 702 | */  | 
            ||
| 703 | protected function getAbstractFileForm($id, $name, $context = [])  | 
            ||
| 742 | |||
| 743 | /**  | 
            ||
| 744 | * Get form for selecting a file  | 
            ||
| 745 | *  | 
            ||
| 746 | * @return Form  | 
            ||
| 747 | */  | 
            ||
| 748 | public function fileSelectForm()  | 
            ||
| 755 | |||
| 756 | /**  | 
            ||
| 757 | * Get form for selecting a file  | 
            ||
| 758 | *  | 
            ||
| 759 | * @param int $id ID of the record being selected  | 
            ||
| 760 | * @return Form  | 
            ||
| 761 | */  | 
            ||
| 762 | public function getFileSelectForm($id)  | 
            ||
| 766 | |||
| 767 | /**  | 
            ||
| 768 | * @param array $context  | 
            ||
| 769 | * @return Form  | 
            ||
| 770 | * @throws InvalidArgumentException  | 
            ||
| 771 | */  | 
            ||
| 772 | public function getFileHistoryForm($context)  | 
            ||
| 819 | |||
| 820 | /**  | 
            ||
| 821 | * Gets a JSON schema representing the current edit form.  | 
            ||
| 822 | *  | 
            ||
| 823 | * WARNING: Experimental API.  | 
            ||
| 824 | *  | 
            ||
| 825 | * @param HTTPRequest $request  | 
            ||
| 826 | * @return HTTPResponse  | 
            ||
| 827 | */  | 
            ||
| 828 | public function schema($request)  | 
            ||
| 851 | |||
| 852 | /**  | 
            ||
| 853 | * Get file history form  | 
            ||
| 854 | *  | 
            ||
| 855 | * @param HTTPRequest $request  | 
            ||
| 856 | * @return Form  | 
            ||
| 857 | */  | 
            ||
| 858 | public function fileHistoryForm($request = null)  | 
            ||
| 881 | |||
| 882 | /**  | 
            ||
| 883 | * @param array $data  | 
            ||
| 884 | * @param Form $form  | 
            ||
| 885 | * @return HTTPResponse  | 
            ||
| 886 | */  | 
            ||
| 887 | public function createfolder($data, $form)  | 
            ||
| 922 | |||
| 923 | /**  | 
            ||
| 924 | * @param array $data  | 
            ||
| 925 | * @param Form $form  | 
            ||
| 926 | * @return HTTPResponse  | 
            ||
| 927 | */  | 
            ||
| 928 | public function save($data, $form)  | 
            ||
| 932 | |||
| 933 | /**  | 
            ||
| 934 | * @param array $data  | 
            ||
| 935 | * @param Form $form  | 
            ||
| 936 | * @return HTTPResponse  | 
            ||
| 937 | */  | 
            ||
| 938 | public function publish($data, $form)  | 
            ||
| 942 | |||
| 943 | /**  | 
            ||
| 944 | * Update thisrecord  | 
            ||
| 945 | *  | 
            ||
| 946 | * @param array $data  | 
            ||
| 947 | * @param Form $form  | 
            ||
| 948 | * @param bool $doPublish  | 
            ||
| 949 | * @return HTTPResponse  | 
            ||
| 950 | */  | 
            ||
| 951 | protected function saveOrPublish($data, $form, $doPublish = false)  | 
            ||
| 1000 | |||
| 1001 | public function unpublish($data, $form)  | 
            ||
| 1025 | |||
| 1026 | /**  | 
            ||
| 1027 | * @param File $file  | 
            ||
| 1028 | *  | 
            ||
| 1029 | * @return array  | 
            ||
| 1030 | */  | 
            ||
| 1031 | public function getObjectFromData(File $file)  | 
            ||
| 1101 | |||
| 1102 | /**  | 
            ||
| 1103 | * Action handler for adding pages to a campaign  | 
            ||
| 1104 | *  | 
            ||
| 1105 | * @param array $data  | 
            ||
| 1106 | * @param Form $form  | 
            ||
| 1107 | * @return DBHTMLText|HTTPResponse  | 
            ||
| 1108 | */  | 
            ||
| 1109 | public function addtocampaign($data, $form)  | 
            ||
| 1125 | |||
| 1126 | /**  | 
            ||
| 1127 | * Url handler for add to campaign form  | 
            ||
| 1128 | *  | 
            ||
| 1129 | * @param HTTPRequest $request  | 
            ||
| 1130 | * @return Form  | 
            ||
| 1131 | */  | 
            ||
| 1132 | public function addToCampaignForm($request)  | 
            ||
| 1138 | |||
| 1139 | /**  | 
            ||
| 1140 | * @param int $id  | 
            ||
| 1141 | * @return Form  | 
            ||
| 1142 | */  | 
            ||
| 1143 | public function getAddToCampaignForm($id)  | 
            ||
| 1177 | |||
| 1178 | /**  | 
            ||
| 1179 | * @return Upload  | 
            ||
| 1180 | */  | 
            ||
| 1181 | protected function getUpload()  | 
            ||
| 1191 | |||
| 1192 | /**  | 
            ||
| 1193 | * Get response for successfully updated record  | 
            ||
| 1194 | *  | 
            ||
| 1195 | * @param File $record  | 
            ||
| 1196 | * @param Form $form  | 
            ||
| 1197 | * @return HTTPResponse  | 
            ||
| 1198 | */  | 
            ||
| 1199 | protected function getRecordUpdatedResponse($record, $form)  | 
            ||
| 1206 | |||
| 1207 | /**  | 
            ||
| 1208 | * @param HTTPRequest $request  | 
            ||
| 1209 | * @return Form  | 
            ||
| 1210 | */  | 
            ||
| 1211 | public function folderCreateForm($request = null)  | 
            ||
| 1226 | |||
| 1227 | /**  | 
            ||
| 1228 | * Returns the form to be used for creating a new folder  | 
            ||
| 1229 | * @param $parentId  | 
            ||
| 1230 | * @return Form  | 
            ||
| 1231 | */  | 
            ||
| 1232 | public function getFolderCreateForm($parentId = 0)  | 
            ||
| 1245 | |||
| 1246 | /**  | 
            ||
| 1247 | * Scaffold a search form.  | 
            ||
| 1248 | * Note: This form does not submit to itself, but rather uses the apiReadFolder endpoint  | 
            ||
| 1249 | * (to be replaced with graphql)  | 
            ||
| 1250 | *  | 
            ||
| 1251 | * @return Form  | 
            ||
| 1252 | */  | 
            ||
| 1253 | public function fileSearchForm()  | 
            ||
| 1258 | |||
| 1259 | /**  | 
            ||
| 1260 | * Allow search form to be accessible to schema  | 
            ||
| 1261 | *  | 
            ||
| 1262 | * @return Form  | 
            ||
| 1263 | */  | 
            ||
| 1264 | public function getFileSearchform()  | 
            ||
| 1268 | }  | 
            ||
| 1269 | 
This check marks private properties in classes that are never used. Those properties can be removed.