**Course Title:** Mastering Symfony: Building Enterprise-Level PHP Applications **Section Title:** API Platform and GraphQL **Topic:** Pagination, filtering, and sorting with API Platform **Introduction** In the previous topic, we explored the basics of API Platform and its capabilities for building robust and scalable APIs. In this topic, we will delve deeper into one of the most important features of API Platform: pagination, filtering, and sorting. These features enable developers to efficiently manage large datasets and provide a better user experience. **What is Pagination?** Pagination is the process of dividing a large dataset into smaller, manageable chunks, called pages. This allows developers to display a limited number of records on each page, making it easier for users to navigate and understand the data. **What is Filtering?** Filtering is the process of applying conditions to a dataset to narrow down the results. This can be done using various criteria, such as date ranges, keywords, or other attributes. **What is Sorting?** Sorting is the process of arranging a dataset in a specific order, such as alphabetical or numerical order. **Implementing Pagination, Filtering, and Sorting with API Platform** API Platform provides a built-in feature for implementing pagination, filtering, and sorting using the `Pagination` and `Filter` classes. Here is an example of how to implement pagination, filtering, and sorting using API Platform: ```php // Define the entity and repository namespace App\Entity; use Doctrine\ORM\EntityRepository; class User extends Entity { // ... } class UserRepository extends EntityRepository { // ... } // Define the controller namespace App\Controller; use App\Entity\User; use App\Repository\UserRepository; use ApiPlatform\Core\Pagination\Pagination; use ApiPlatform\Core\Pagination\PaginationInterface; class UserController extends Controller { private $userRepository; public function __construct(UserRepository $userRepository) { $this->userRepository = $userRepository; } public function getUsers(PaginationInterface $pagination) { $users = $this->userRepository->findAll(); // Implement pagination $pagination->setPage($pagination->getPage()); $pagination->setPerPage($pagination->getPerPage()); $users = $pagination->paginate($users); // Implement filtering $filter = new Filter(); $filter->addFilter('name', 'like', 'John'); $users = $filter->apply($users); // Implement sorting $sort = new Sort(); $sort->addSort('name', 'asc'); $users = $sort->apply($users); return $users; } } ``` In this example, we define a `User` entity and a `UserRepository` class. We then define a `UserController` class that implements the `getUsers` method. This method uses the `Pagination` and `Filter` classes to implement pagination, filtering, and sorting. **Using the `Pagination` Class** The `Pagination` class provides a simple way to implement pagination. You can use the `setPage` and `setPerPage` methods to set the page number and number of items per page. Here is an example of how to use the `Pagination` class: ```php $pagination = new Pagination(); $pagination->setPage(1); $pagination->setPerPage(10); $users = $pagination->paginate($users); ``` **Using the `Filter` Class** The `Filter` class provides a simple way to implement filtering. You can use the `addFilter` method to add filters to the query. Here is an example of how to use the `Filter` class: ```php $filter = new Filter(); $filter->addFilter('name', 'like', 'John'); $users = $filter->apply($users); ``` **Using the `Sort` Class** The `Sort` class provides a simple way to implement sorting. You can use the `addSort` method to add sorts to the query. Here is an example of how to use the `Sort` class: ```php $sort = new Sort(); $sort->addSort('name', 'asc'); $users = $sort->apply($users); ``` **Conclusion** In this topic, we explored the basics of pagination, filtering, and sorting with API Platform. We learned how to implement these features using the `Pagination`, `Filter`, and `Sort` classes. We also saw examples of how to use these classes to implement pagination, filtering, and sorting in a real-world scenario. **Practical Takeaways** * Use the `Pagination` class to implement pagination. * Use the `Filter` class to implement filtering. * Use the `Sort` class to implement sorting. * Use the `setPage` and `setPerPage` methods to set the page number and number of items per page. * Use the `addFilter` method to add filters to the query. * Use the `addSort` method to add sorts to the query. **Additional Resources** * API Platform documentation: <https://api-platform.com/docs/> * Symfony documentation: <https://symfony.com/doc/current/> **Leave a comment or ask for help** If you have any questions or need further clarification on any of the topics covered in this topic, please leave a comment below. I'll be happy to help.