/lampager-cakephp

Rapid pagination for CakePHP

Primary LanguagePHPMIT LicenseMIT

lampager-cakephp

CI Workflow Coverage Status Scrutinizer Code Quality

Lampager for CakePHP

Rapid pagination without using OFFSET

Requirements

Note

Installing

composer require lampager/lampager-cakephp:^2.0

For SQLite users, see SQLite to configure.

Basic Usage

Simply install as a Composer package and use in one or more of the following methods:

  • Use in Controller (via \Lampager\Cake\Datasource\Paginator)
  • Use in Table (via \Lampager\Cake\Model\Behavior\LampagerBehavior)

Use in Controller

At first, configure $paginate to use \Lampager\Cake\Datasource\Paginator in your Controller class.

namespace App\Controller;

use Cake\Controller\Controller;
use Lampager\Cake\Datasource\Paginator;

class AppController extends Controller
{
    public $paginate = [
        'className' => Paginator::class,
    ];
}

Use in a way described in the Cookbook: Pagination. Note the options that are specific to Lampager such as forward, seekable, or cursor.

$query = $this->Posts
    ->where(['Posts.type' => 'public'])
    ->orderDesc('created')
    ->orderDesc('id')
    ->limit(10);

$posts = $this->paginate($query, [
    'forward' => true,
    'seekable' => true,
    'cursor' => [
        'id' => 4,
        'created' => '2020-01-01 10:00:00',
    ],
]);

$this->set('posts', $posts);

Use in Table

Initialize LampagerBehavior in your Table class (AppTable is preferable) and simply use lampager() there.

namespace App\Model\Table;

use Cake\ORM\Table;
use Lampager\Cake\Model\Behavior\LampagerBehavior;

class AppTable extends Table
{
    public function initialize(array $config): void
    {
        parent::initialize($config);

        $this->addBehavior(LampagerBehavior::class);
    }
}

The query builder (\Lampager\Cake\ORM\Query) extends the plain old \Cake\ORM\Query and is mixed in with \Lampager\Paginator. Note that some of the methods in \Lampager\Paginator, viz., orderBy(), orderByDesc(), and clearOrderBy() are not exposed because their method signatures are not compatible with the CakePHP query builder.

$cursor = [
    'id' => 4,
    'created' => '2020-01-01 10:00:00',
    'modified' => '2020-01-01 12:00:00',
];

/** @var \Lampager\Cake\PaginationResult $latest */
$latest = $this->lampager()
    ->forward()
    ->seekable()
    ->cursor($cursor)
    ->limit(10)
    ->orderDesc('Posts.modified')
    ->orderDesc('Posts.created')
    ->orderDesc('Posts.id');

foreach ($latest as $post) {
    /** @var \Cake\ORM\Entity $post */
    debug($post->id);
    debug($post->created);
    debug($post->modified);
}

The methods from the CakePHP query builder, e.g., where(), are available. \Cake\Database\Expression\QueryExpression is accepted as well.

/** @var \Lampager\Cake\PaginationResult $drafts */
$drafts = $this->lampager()
    ->where(['type' => 'draft'])
    ->forward()
    ->seekable()
    ->cursor($cursor)
    ->limit(10)
    ->orderDesc($this->query()->newExpr('modified'))
    ->orderDesc($this->query()->newExpr('created'))
    ->orderDesc($this->query()->newExpr('id'));

/** @var \Cake\ORM\Entity $sample */
$sample = $drafts->sample();

/** @var int $count */
$count = $drafts->count();

Classes

See also: lampager/lampager.

Name Type Parent Class
Implemented Interface
Description
Lampager\Cake\ORM\Query Class Cake\ORM\Query Fluent factory implementation for CakePHP
Lampager\Cake\Model\Behavior\LampagerBehavior Class Cake\ORM\Behavior CakePHP behavior which returns Lampager\Cake\ORM\Query
Lampager\Cake\Datasource\Paginator Class Cake\Datasource\Paginator CakePHP paginatior which delegates to Lampager\Cake\ORM\Query
Lampager\Cake\Paginator Class Lampager\Paginator Paginator implementation for CakePHP
Lampager\Cake\ArrayProcessor Class Lampager\ArrayProcessor Processor implementation for CakePHP
Lampager\Cake\PaginationResult Class Cake\Datasource\ResultSetInterface PaginationResult implementation for CakePHP
Lampager\Cake\Database\SqliteCompiler Class Cake\Database\SqliteCompiler Query compiler implementation for SQLite
Lampager\Cake\Database\Driver\Sqlite Class Cake\Database\Driver\Sqlite Driver implementation which delegates to Lampager\Cake\Database\SqliteCompiler

Note that \Lampager\Cake\PaginationResult does not extend \Lampager\PaginationResult as it conflicts with \Cake\Datasource\ResultSetInterface.

API

See also: lampager/lampager.

LampagerBehavior::lampager()

Build a Lampager query from Table in exactly the same way as CakePHP.

LampagerBehavior::lampager(): \Lampager\Cake\ORM\Query

Paginator::__construct()
Paginator::create()

Create a new paginator instance. These methods are not intended to be directly used in your code.

static Paginator::create(\Cake\ORM\Query $builder): static
Paginator::__construct(\Cake\ORM\Query $builder)

Paginator::transform()

Transform a Lampager query into a CakePHP query.

Paginator::transform(\Lampager\Query $query): \Cake\ORM\Query

Paginator::build()

Perform configure + transform.

Paginator::build(\Lampager\Contracts\Cursor|array $cursor = []): \Cake\ORM\Query

Paginator::paginate()

Perform configure + transform + process.

Paginator::paginate(\Lampager\Contracts\Cursor|array $cursor = []): \Lampager\Cake\PaginationResult

Arguments

  • (mixed) $cursor
    An associative array that contains $column => $value or an object that implements \Lampager\Contracts\Cursor. It must be all-or-nothing.
    • For the initial page, omit this parameter or pass an empty array.
    • For the subsequent pages, pass all the parameters. The partial one is not allowed.

Return Value

e.g.,

(Default format when using \Cake\ORM\Query)

object(Lampager\Cake\PaginationResult)#1 (6) {
  ["(help)"]=>
  string(44) "This is a Lampager Pagination Result object."
  ["records"]=>
  array(3) {
    [0]=>
    object(Cake\ORM\Entity)#2 (11) { ... }
    [1]=>
    object(Cake\ORM\Entity)#3 (11) { ... }
    [2]=>
    object(Cake\ORM\Entity)#4 (11) { ... }
  ["hasPrevious"]=>
  bool(false)
  ["previousCursor"]=>
  NULL
  ["hasNext"]=>
  bool(true)
  ["nextCursor"]=>
  array(2) {
    ["created"]=>
    object(Cake\I18n\Time)#5 (3) {
      ["date"]=>
      string(26) "2017-01-01 10:00:00.000000"
      ["timezone_type"]=>
      int(3)
      ["timezone"]=>
      string(3) "UTC"
    }
    ["id"]=>
    int(1)
  }
}

PaginationResult::__call()

\Lampager\Cake\PaginationResult implements \Cake\Datasource\ResultSetInterface. For how to make the best use of the PaginationResult, please refer to the Cookbook: Working with Result Sets.

Examples

This section describes the practical usage of lampager-cakephp.

Use in Controller

The example below shows how to accept a cursor parameter from a request and pass it through PaginatorComponent::paginate(). Be sure that your AppController has properly initialized Paginator as above.

namespace App\Controller;

class PostsController extends AppController
{
    /**
     * This method shows how to pass options by a query and array.
     */
    public function query(): void
    {
        // Get cursor parameters
        $previous = json_decode($this->request->getQuery('previous_cursor'), true);
        $next = json_decode($this->request->getQuery('next_cursor'), true);
        $cursor = $previous ?: $next ?: [];

        // Query expression can be passed to PaginatorComponent::paginate() as normal
        $query = $this->Posts
            ->where(['Posts.type' => 'public'])
            ->orderDesc('created')
            ->orderDesc('id')
            ->limit(15);

        /** @var \Lampager\Cake\PaginationResult<\Cake\ORM\Entity> $posts */
        $posts = $this->paginate($query, [
            // If the previous_cursor is not set, paginate forward; otherwise backward
            'forward' => !$previous,
            'cursor' => $cursor,
            'seekable' => true,
        ]);

        $this->set('posts', $posts);
    }

    /**
     * This method shows how to pass options from an array.
     */
    public function options(): void
    {
        // Get cursor parameters
        $previous = json_decode($this->request->getQuery('previous_cursor'), true);
        $next = json_decode($this->request->getQuery('next_cursor'), true);
        $cursor = $previous ?: $next ?: [];

        /** @var \Lampager\Cake\PaginationResult<\Cake\ORM\Entity> $posts */
        $posts = $this->paginate('Posts', [
            // Lampager options
            // If the previous_cursor is not set, paginate forward; otherwise backward
            'forward' => !$previous,
            'cursor' => $cursor,
            'seekable' => true,

            // PaginatorComponent config
            'conditions' => [
                'type' => 'public',
            ],
            'order' => [
                'created' => 'DESC',
                'id' => 'DESC',
            ],
            'limit' => 15,
        ]);

        $this->set('posts', $posts);
    }
}

And the pagination links can be output as follows:

// If there is a next page, print pagination link
if ($posts->hasPrevious) {
    echo $this->Html->link('<< Previous', [
        'controller' => 'posts',
        'action' => 'index',
        '?' => [
            'previous_cursor' => json_encode($posts->previousCursor),
        ],
    ]);
}

// If there is a next page, print pagination link
if ($posts->hasNext) {
    echo $this->Html->link('Next >>', [
        'controller' => 'posts',
        'action' => 'index',
        '?' => [
            'next_cursor' => json_encode($posts->nextCursor),
        ],
    ]);
}

Supported database engines

MySQL, MariaDB, and PostgreSQL

Supported!

Microsoft SQL Server

Not supported.

SQLite

Supported but requires an additional configuration.

In SQLite UNION ALL statements cannot combine SELECT statements that have ORDER BY clause. In order to get this to work, those SELECT statements have to be wrapped by a subquery like SELECT * FROM (...). CakePHP not natively handling this situation, Lampager for CakePHP introduces \Lampager\Cake\Database\Driver\Sqlite that needs to be installed on your application. Configure like the following in your config/app.php:

return [
    'Datasources' => [
        'default' => [
            'className' => Connection::class,
            'driver' => \Lampager\Cake\Database\Driver\Sqlite::class,
            'username' => '********',
            'password' => '********',
            'database' => '********',
        ],
    ],
];