1: <?php
  2: /**
  3:  * Paginator Component
  4:  *
  5:  * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
  6:  * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
  7:  *
  8:  * Licensed under The MIT License
  9:  * For full copyright and license information, please see the LICENSE.txt
 10:  * Redistributions of files must retain the above copyright notice.
 11:  *
 12:  * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 13:  * @link          http://cakephp.org CakePHP(tm) Project
 14:  * @package       Cake.Controller.Component
 15:  * @since         CakePHP(tm) v 2.0
 16:  * @license       http://www.opensource.org/licenses/mit-license.php MIT License
 17:  */
 18: 
 19: App::uses('Component', 'Controller');
 20: App::uses('Hash', 'Utility');
 21: 
 22: /**
 23:  * This component is used to handle automatic model data pagination. The primary way to use this
 24:  * component is to call the paginate() method. There is a convenience wrapper on Controller as well.
 25:  *
 26:  * ### Configuring pagination
 27:  *
 28:  * You configure pagination using the PaginatorComponent::$settings. This allows you to configure
 29:  * the default pagination behavior in general or for a specific model. General settings are used when there
 30:  * are no specific model configuration, or the model you are paginating does not have specific settings.
 31:  *
 32:  * ```
 33:  *  $this->Paginator->settings = array(
 34:  *      'limit' => 20,
 35:  *      'maxLimit' => 100
 36:  *  );
 37:  * ```
 38:  *
 39:  * The above settings will be used to paginate any model. You can configure model specific settings by
 40:  * keying the settings with the model name.
 41:  *
 42:  * ```
 43:  *  $this->Paginator->settings = array(
 44:  *      'Post' => array(
 45:  *          'limit' => 20,
 46:  *          'maxLimit' => 100
 47:  *      ),
 48:  *      'Comment' => array( ... )
 49:  *  );
 50:  * ```
 51:  *
 52:  * This would allow you to have different pagination settings for `Comment` and `Post` models.
 53:  *
 54:  * #### Paginating with custom finders
 55:  *
 56:  * You can paginate with any find type defined on your model using the `findType` option.
 57:  *
 58:  * ```
 59:  * $this->Paginator->settings = array(
 60:  *      'Post' => array(
 61:  *          'findType' => 'popular'
 62:  *      )
 63:  * );
 64:  * ```
 65:  *
 66:  * Would paginate using the `find('popular')` method.
 67:  *
 68:  * @package       Cake.Controller.Component
 69:  * @link http://book.cakephp.org/2.0/en/core-libraries/components/pagination.html
 70:  */
 71: class PaginatorComponent extends Component {
 72: 
 73: /**
 74:  * Pagination settings. These settings control pagination at a general level.
 75:  * You can also define sub arrays for pagination settings for specific models.
 76:  *
 77:  * - `maxLimit` The maximum limit users can choose to view. Defaults to 100
 78:  * - `limit` The initial number of items per page. Defaults to 20.
 79:  * - `page` The starting page, defaults to 1.
 80:  * - `paramType` What type of parameters you want pagination to use?
 81:  *      - `named` Use named parameters / routed parameters.
 82:  *      - `querystring` Use query string parameters.
 83:  *
 84:  * @var array
 85:  */
 86:     public $settings = array(
 87:         'page' => 1,
 88:         'limit' => 20,
 89:         'maxLimit' => 100,
 90:         'paramType' => 'named'
 91:     );
 92: 
 93: /**
 94:  * A list of parameters users are allowed to set using request parameters. Modifying
 95:  * this list will allow users to have more influence over pagination,
 96:  * be careful with what you permit.
 97:  *
 98:  * @var array
 99:  */
100:     public $whitelist = array(
101:         'limit', 'sort', 'page', 'direction'
102:     );
103: 
104: /**
105:  * Constructor
106:  *
107:  * @param ComponentCollection $collection A ComponentCollection this component can use to lazy load its components
108:  * @param array $settings Array of configuration settings.
109:  */
110:     public function __construct(ComponentCollection $collection, $settings = array()) {
111:         $settings = array_merge($this->settings, (array)$settings);
112:         $this->Controller = $collection->getController();
113:         parent::__construct($collection, $settings);
114:     }
115: 
116: /**
117:  * Handles automatic pagination of model records.
118:  *
119:  * @param Model|string $object Model to paginate (e.g: model instance, or 'Model', or 'Model.InnerModel')
120:  * @param string|array $scope Additional find conditions to use while paginating
121:  * @param array $whitelist List of allowed fields for ordering. This allows you to prevent ordering
122:  *   on non-indexed, or undesirable columns. See PaginatorComponent::validateSort() for additional details
123:  *   on how the whitelisting and sort field validation works.
124:  * @return array Model query results
125:  * @throws MissingModelException
126:  * @throws NotFoundException
127:  */
128:     public function paginate($object = null, $scope = array(), $whitelist = array()) {
129:         if (is_array($object)) {
130:             $whitelist = $scope;
131:             $scope = $object;
132:             $object = null;
133:         }
134: 
135:         $object = $this->_getObject($object);
136: 
137:         if (!is_object($object)) {
138:             throw new MissingModelException($object);
139:         }
140: 
141:         $options = $this->mergeOptions($object->alias);
142:         $options = $this->validateSort($object, $options, $whitelist);
143:         $options = $this->checkLimit($options);
144: 
145:         $conditions = $fields = $order = $limit = $page = $recursive = null;
146: 
147:         if (!isset($options['conditions'])) {
148:             $options['conditions'] = array();
149:         }
150: 
151:         $type = 'all';
152: 
153:         if (isset($options[0])) {
154:             $type = $options[0];
155:             unset($options[0]);
156:         }
157: 
158:         extract($options);
159: 
160:         if (is_array($scope) && !empty($scope)) {
161:             $conditions = array_merge($conditions, $scope);
162:         } elseif (is_string($scope)) {
163:             $conditions = array($conditions, $scope);
164:         }
165:         if ($recursive === null) {
166:             $recursive = $object->recursive;
167:         }
168: 
169:         $extra = array_diff_key($options, compact(
170:             'conditions', 'fields', 'order', 'limit', 'page', 'recursive'
171:         ));
172: 
173:         if (!empty($extra['findType'])) {
174:             $type = $extra['findType'];
175:             unset($extra['findType']);
176:         }
177: 
178:         if ($type !== 'all') {
179:             $extra['type'] = $type;
180:         }
181: 
182:         if ((int)$page < 1) {
183:             $page = 1;
184:         }
185:         $page = $options['page'] = (int)$page;
186: 
187:         if ($object->hasMethod('paginate')) {
188:             $results = $object->paginate(
189:                 $conditions, $fields, $order, $limit, $page, $recursive, $extra
190:             );
191:         } else {
192:             $parameters = compact('conditions', 'fields', 'order', 'limit', 'page');
193:             if ($recursive != $object->recursive) {
194:                 $parameters['recursive'] = $recursive;
195:             }
196:             $results = $object->find($type, array_merge($parameters, $extra));
197:         }
198:         $defaults = $this->getDefaults($object->alias);
199:         unset($defaults[0]);
200: 
201:         if (!$results) {
202:             $count = 0;
203:         } elseif ($object->hasMethod('paginateCount')) {
204:             $count = $object->paginateCount($conditions, $recursive, $extra);
205:         } elseif ($page === 1 && count($results) < $limit) {
206:             $count = count($results);
207:         } else {
208:             $parameters = compact('conditions');
209:             if ($recursive != $object->recursive) {
210:                 $parameters['recursive'] = $recursive;
211:             }
212:             $count = $object->find('count', array_merge($parameters, $extra));
213:         }
214:         $pageCount = (int)ceil($count / $limit);
215:         $requestedPage = $page;
216:         $page = max(min($page, $pageCount), 1);
217: 
218:         $paging = array(
219:             'page' => $page,
220:             'current' => count($results),
221:             'count' => $count,
222:             'prevPage' => ($page > 1),
223:             'nextPage' => ($count > ($page * $limit)),
224:             'pageCount' => $pageCount,
225:             'order' => $order,
226:             'limit' => $limit,
227:             'options' => Hash::diff($options, $defaults),
228:             'paramType' => $options['paramType']
229:         );
230: 
231:         if (!isset($this->Controller->request['paging'])) {
232:             $this->Controller->request['paging'] = array();
233:         }
234:         $this->Controller->request['paging'] = array_merge(
235:             (array)$this->Controller->request['paging'],
236:             array($object->alias => $paging)
237:         );
238: 
239:         if ($requestedPage > $page) {
240:             throw new NotFoundException();
241:         }
242: 
243:         if (!in_array('Paginator', $this->Controller->helpers) &&
244:             !array_key_exists('Paginator', $this->Controller->helpers)
245:         ) {
246:             $this->Controller->helpers[] = 'Paginator';
247:         }
248:         return $results;
249:     }
250: 
251: /**
252:  * Get the object pagination will occur on.
253:  *
254:  * @param string|Model $object The object you are looking for.
255:  * @return mixed The model object to paginate on.
256:  */
257:     protected function _getObject($object) {
258:         if (is_string($object)) {
259:             $assoc = null;
260:             if (strpos($object, '.') !== false) {
261:                 list($object, $assoc) = pluginSplit($object);
262:             }
263:             if ($assoc && isset($this->Controller->{$object}->{$assoc})) {
264:                 return $this->Controller->{$object}->{$assoc};
265:             }
266:             if ($assoc && isset($this->Controller->{$this->Controller->modelClass}->{$assoc})) {
267:                 return $this->Controller->{$this->Controller->modelClass}->{$assoc};
268:             }
269:             if (isset($this->Controller->{$object})) {
270:                 return $this->Controller->{$object};
271:             }
272:             if (isset($this->Controller->{$this->Controller->modelClass}->{$object})) {
273:                 return $this->Controller->{$this->Controller->modelClass}->{$object};
274:             }
275:         }
276:         if (empty($object) || $object === null) {
277:             if (isset($this->Controller->{$this->Controller->modelClass})) {
278:                 return $this->Controller->{$this->Controller->modelClass};
279:             }
280: 
281:             $className = null;
282:             $name = $this->Controller->uses[0];
283:             if (strpos($this->Controller->uses[0], '.') !== false) {
284:                 list($name, $className) = explode('.', $this->Controller->uses[0]);
285:             }
286:             if ($className) {
287:                 return $this->Controller->{$className};
288:             }
289: 
290:             return $this->Controller->{$name};
291:         }
292:         return $object;
293:     }
294: 
295: /**
296:  * Merges the various options that Pagination uses.
297:  * Pulls settings together from the following places:
298:  *
299:  * - General pagination settings
300:  * - Model specific settings.
301:  * - Request parameters
302:  *
303:  * The result of this method is the aggregate of all the option sets combined together. You can change
304:  * PaginatorComponent::$whitelist to modify which options/values can be set using request parameters.
305:  *
306:  * @param string $alias Model alias being paginated, if the general settings has a key with this value
307:  *   that key's settings will be used for pagination instead of the general ones.
308:  * @return array Array of merged options.
309:  */
310:     public function mergeOptions($alias) {
311:         $defaults = $this->getDefaults($alias);
312:         switch ($defaults['paramType']) {
313:             case 'named':
314:                 $request = $this->Controller->request->params['named'];
315:                 break;
316:             case 'querystring':
317:                 $request = $this->Controller->request->query;
318:                 break;
319:         }
320:         $request = array_intersect_key($request, array_flip($this->whitelist));
321:         return array_merge($defaults, $request);
322:     }
323: 
324: /**
325:  * Get the default settings for a $model. If there are no settings for a specific model, the general settings
326:  * will be used.
327:  *
328:  * @param string $alias Model name to get default settings for.
329:  * @return array An array of pagination defaults for a model, or the general settings.
330:  */
331:     public function getDefaults($alias) {
332:         $defaults = $this->settings;
333:         if (isset($this->settings[$alias])) {
334:             $defaults = $this->settings[$alias];
335:         }
336:         $defaults += array(
337:             'page' => 1,
338:             'limit' => 20,
339:             'maxLimit' => 100,
340:             'paramType' => 'named'
341:         );
342:         return $defaults;
343:     }
344: 
345: /**
346:  * Validate that the desired sorting can be performed on the $object. Only fields or
347:  * virtualFields can be sorted on. The direction param will also be sanitized. Lastly
348:  * sort + direction keys will be converted into the model friendly order key.
349:  *
350:  * You can use the whitelist parameter to control which columns/fields are available for sorting.
351:  * This helps prevent users from ordering large result sets on un-indexed values.
352:  *
353:  * Any columns listed in the sort whitelist will be implicitly trusted. You can use this to sort
354:  * on synthetic columns, or columns added in custom find operations that may not exist in the schema.
355:  *
356:  * @param Model $object The model being paginated.
357:  * @param array $options The pagination options being used for this request.
358:  * @param array $whitelist The list of columns that can be used for sorting. If empty all keys are allowed.
359:  * @return array An array of options with sort + direction removed and replaced with order if possible.
360:  */
361:     public function validateSort(Model $object, array $options, array $whitelist = array()) {
362:         if (empty($options['order']) && is_array($object->order)) {
363:             $options['order'] = $object->order;
364:         }
365: 
366:         if (isset($options['sort'])) {
367:             $direction = null;
368:             if (isset($options['direction'])) {
369:                 $direction = strtolower($options['direction']);
370:             }
371:             if (!in_array($direction, array('asc', 'desc'))) {
372:                 $direction = 'asc';
373:             }
374:             $options['order'] = array($options['sort'] => $direction);
375:         }
376: 
377:         if (!empty($whitelist) && isset($options['order']) && is_array($options['order'])) {
378:             $field = key($options['order']);
379:             $inWhitelist = in_array($field, $whitelist, true);
380:             if (!$inWhitelist) {
381:                 $options['order'] = null;
382:             }
383:             return $options;
384:         }
385: 
386:         if (!empty($options['order']) && is_array($options['order'])) {
387:             $order = array();
388:             foreach ($options['order'] as $key => $value) {
389:                 if (is_int($key)) {
390:                     $key = $value;
391:                     $value = 'asc';
392:                 }
393:                 $field = $key;
394:                 $alias = $object->alias;
395:                 if (strpos($key, '.') !== false) {
396:                     list($alias, $field) = explode('.', $key);
397:                 }
398:                 $correctAlias = ($object->alias === $alias);
399: 
400:                 if ($correctAlias && $object->hasField($field)) {
401:                     $order[$object->alias . '.' . $field] = $value;
402:                 } elseif ($correctAlias && $object->hasField($key, true)) {
403:                     $order[$field] = $value;
404:                 } elseif (isset($object->{$alias}) && $object->{$alias}->hasField($field, true)) {
405:                     $order[$alias . '.' . $field] = $value;
406:                 }
407:             }
408:             $options['order'] = $order;
409:         }
410: 
411:         return $options;
412:     }
413: 
414: /**
415:  * Check the limit parameter and ensure its within the maxLimit bounds.
416:  *
417:  * @param array $options An array of options with a limit key to be checked.
418:  * @return array An array of options for pagination
419:  */
420:     public function checkLimit(array $options) {
421:         $options['limit'] = (int)$options['limit'];
422:         if (empty($options['limit']) || $options['limit'] < 1) {
423:             $options['limit'] = 1;
424:         }
425:         $options['limit'] = min($options['limit'], $options['maxLimit']);
426:         return $options;
427:     }
428: 
429: }
430: