Pagination

  • class Cake\Controller\Component\PaginatorComponent

One of the main obstacles of creating flexible and user-friendly webapplications is designing an intuitive user interface. Many applications tend togrow in size and complexity quickly, and designers and programmers alike findthey are unable to cope with displaying hundreds or thousands of records.Refactoring takes time, and performance and user satisfaction can suffer.

Displaying a reasonable number of records per page has always been a criticalpart of every application and used to cause many headaches for developers.CakePHP eases the burden on the developer by providing a quick, easy way topaginate data.

Pagination in CakePHP is offered by a component in the controller. You then useView\Helper\PaginatorHelper in your view templates togenerate pagination controls.

Basic Usage

To paginate a query we first need to load the PaginatorComponent:

  1. class ArticlesController extends AppController
  2. {
  3. public function initialize(): void
  4. {
  5. parent::initialize();
  6. $this->loadComponent('Paginator');
  7. }
  8. }

Once loaded we can paginate an ORM table class or Query object:

  1. public function index()
  2. {
  3. // Paginate the ORM table.
  4. $this->set('articles', $this->paginate($this->Articles));
  5.  
  6. // Paginate a partially completed query
  7. $query = $this->Articles->find('published');
  8. $this->('articles', $this->paginate($query));
  9. }

Advanced Usage

PaginatorComponent supports more complex use cases by configuring the $paginatecontroller property or as the $settings argument to paginate(). Theseconditions service as the basis for you pagination queries. They are augmentedby the sort, direction, limit, and page parameters passed infrom the URL:

  1. class ArticlesController extends AppController
  2. {
  3. public $paginate = [
  4. 'limit' => 25,
  5. 'order' => [
  6. 'Articles.title' => 'asc'
  7. ]
  8. ];
  9. }

Tip

Default order options must be defined as an array.

While you can include any of the options supported byORM\Table::find() such as fields in your paginationsettings. It is cleaner and simpler to bundle your pagination options intoa Custom Finder Methods. You can use your finder in pagination by using thefinder option:

  1. class ArticlesController extends AppController
  2. {
  3. public $paginate = [
  4. 'finder' => 'published',
  5. ];
  6. }

If your finder method requires additional options you can pass thoseas values for the finder:

  1. class ArticlesController extends AppController
  2. {
  3. // find articles by tag
  4. public function tags()
  5. {
  6. $tags = $this->request->getParam('pass');
  7.  
  8. $customFinderOptions = [
  9. 'tags' => $tags
  10. ];
  11. // We're using the $settings argument to paginate() here.
  12. // But the same structure could be used in $this->paginate
  13. //
  14. // Our custom finder is called findTagged inside ArticlesTable.php
  15. // which is why we're using `tagged` as the key.
  16. // Our finder should look like:
  17. // public function findTagged(Query $query, array $options) {
  18. $settings = [
  19. 'finder' => [
  20. 'tagged' => $customFinderOptions
  21. ]
  22. ];
  23. $articles = $this->paginate($this->Articles, $settings);
  24. $this->set(compact('articles', 'tags'));
  25. }
  26. }

In addition to defining general pagination values, you can define more than oneset of pagination defaults in the controller. The name of each model can be usedas a key in the $paginate property:

  1. class ArticlesController extends AppController
  2. {
  3. public $paginate = [
  4. 'Articles' => [],
  5. 'Authors' => [],
  6. ];
  7. }

The values of the Articles and Authors keys could contain all theproperties that a basic $paginate array would.

Once you have used paginate() to create results. The controller’s requestwill be updated with paging parameters. You can access the pagination metadataat $this->request->getParam('paging').

Simple Pagination

By default pagination uses a count() query to calculate the size of theresult set so that page number links can be rendered. On very large datasetsthis count query can be very expensive. In situations where you only want toshow ‘Next’ and ‘Previous’ links you can use the ‘simple’ paginator which doesnot do a count query:

  1. public function initialize()
  2. {
  3. parent::initialize();
  4.  
  5. // Load the paginator component with the simple paginator strategy.
  6. $this->loadComponent('Paginator', [
  7. 'paginator' => new \Cake\Datasource\SimplePaginator(),
  8. ]);
  9. }

When using the SimplePaginator you will not be able to generate pagenumbers, counter data, links to the last page, or total record count controls.

Using the PaginatorComponent Directly

If you need to paginate data from another component you may want to use thePaginatorComponent directly. It features a similar API to the controllermethod:

  1. $articles = $this->Paginator->paginate($articleTable->find(), $config);
  2.  
  3. // Or
  4. $articles = $this->Paginator->paginate($articleTable, $config);

The first parameter should be the query object from a find on table object youwish to paginate results from. Optionally, you can pass the table object and letthe query be constructed for you. The second parameter should be the array ofsettings to use for pagination. This array should have the same structure as the$paginate property on a controller. When paginating a Query object, thefinder option will be ignored. It is assumed that you are passing inthe query you want paginated.

Paginating Multiple Queries

You can paginate multiple models in a single controller action, using thescope option both in the controller’s $paginate property and in thecall to the paginate() method:

  1. // Paginate property
  2. public $paginate = [
  3. 'Articles' => ['scope' => 'article'],
  4. 'Tags' => ['scope' => 'tag']
  5. ];
  6.  
  7. // In a controller action
  8. $articles = $this->paginate($this->Articles, ['scope' => 'article']);
  9. $tags = $this->paginate($this->Tags, ['scope' => 'tag']);
  10. $this->set(compact('articles', 'tags'));

The scope option will result in PaginatorComponent looking inscoped query string parameters. For example, the following URL could be used topaginate both tags and articles at the same time:

  1. /dashboard?article[page]=1&tag[page]=3

See the Paginating Multiple Results section for how to generate scoped HTMLelements and URLs for pagination.

Paginating the Same Model multiple Times

To paginate the same model multiple times within a single controller action youneed to define an alias for the model. See Using the TableLocator foradditional details on how to use the table registry:

  1. // In a controller action
  2. $this->paginate = [
  3. 'ArticlesTable' => [
  4. 'scope' => 'published_articles',
  5. 'limit' => 10,
  6. 'order' => [
  7. 'id' => 'desc',
  8. ],
  9. ],
  10. 'UnpublishedArticlesTable' => [
  11. 'scope' => 'unpublished_articles',
  12. 'limit' => 10,
  13. 'order' => [
  14. 'id' => 'desc',
  15. ],
  16. ],
  17. ];
  18.  
  19. // Register an additional table object to allow differentiating in pagination component
  20. TableRegistry::getTableLocator()->setConfig('UnpublishedArticles', [
  21. 'className' => 'App\Model\Table\ArticlesTable',
  22. 'table' => 'articles',
  23. 'entityClass' => 'App\Model\Entity\Article',
  24. ]);
  25.  
  26. $publishedArticles = $this->paginate(
  27. $this->Articles->find('all', [
  28. 'scope' => 'published_articles'
  29. ])->where(['published' => true])
  30. );
  31.  
  32. $unpublishedArticles = $this->paginate(
  33. TableRegistry::getTableLocator()->get('UnpublishedArticles')->find('all', [
  34. 'scope' => 'unpublished_articles'
  35. ])->where(['published' => false])
  36. );

Control which Fields Used for Ordering

By default sorting can be done on any non-virtual column a table has. This issometimes undesirable as it allows users to sort on un-indexed columns that canbe expensive to order by. You can set the whitelist of fields that can be sortedusing the sortWhitelist option. This option is required when you want tosort on any associated data, or computed fields that may be part of yourpagination query:

  1. public $paginate = [
  2. 'sortWhitelist' => [
  3. 'id', 'title', 'Users.username', 'created'
  4. ]
  5. ];

Any requests that attempt to sort on fields not in the whitelist will beignored.

Limit the Maximum Number of Rows per Page

The number of results that are fetched per page is exposed to the user as thelimit parameter. It is generally undesirable to allow users to fetch allrows in a paginated set. The maxLimit option asserts that no one can setthis limit too high from the outside. By default CakePHP limits the maximumnumber of rows that can be fetched to 100. If this default is not appropriatefor your application, you can adjust it as part of the pagination options, forexample reducing it to 10:

  1. public $paginate = [
  2. // Other keys here.
  3. 'maxLimit' => 10
  4. ];

If the request’s limit param is greater than this value, it will be reduced tothe maxLimit value.

Joining Additional Associations

Additional associations can be loaded to the paginated table by using thecontain parameter:

  1. public function index()
  2. {
  3. $this->paginate = [
  4. 'contain' => ['Authors', 'Comments']
  5. ];
  6.  
  7. $this->set('articles', $this->paginate($this->Articles));
  8. }

Out of Range Page Requests

The PaginatorComponent will throw a NotFoundException when trying toaccess a non-existent page, i.e. page number requested is greater than totalpage count.

So you could either let the normal error page be rendered or use a try catchblock and take appropriate action when a NotFoundException is caught:

  1. use Cake\Http\Exception\NotFoundException;
  2.  
  3. public function index()
  4. {
  5. try {
  6. $this->paginate();
  7. } catch (NotFoundException $e) {
  8. // Do something here like redirecting to first or last page.
  9. // $this->request->getAttribute('paging') will give you required info.
  10. }
  11. }

Pagination in the View

Check the View\Helper\PaginatorHelper documentation forhow to create links for pagination navigation.