PHP code example of yii2-extensions / nested-sets-behavior

    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

yii2-extensions / nested-sets-behavior example snippets

declare(strict_types=1);

use yii\console\controllers\MigrateController;

// console/config/main.php
return [
    'controllerMap' => [
        'migrate' => [
            'class' => MigrateController::class,
            'migrationPath' => [
                '@console/migrations',
                '@vendor/yii2-extensions/nested-sets-behavior/migrations',
            ],
        ],
    ],
];

declare(strict_types=1);

use yii\db\ActiveRecord;
use yii2\extensions\nestedsets\NestedSetsBehavior;

/**
 * @phpstan-property int $depth
 * @phpstan-property int $id
 * @phpstan-property int $lft
 * @phpstan-property int $rgt
 */
class Category extends ActiveRecord
{
    public static function tableName(): string
    {
        return '{{%category}}';
    }

    public function behaviors(): array
    {
        return [
            'nestedSets' => [
                'class' => NestedSetsBehavior::class,
                // 'treeAttribute' => 'tree', // Enable for multiple trees
                // 'leftAttribute' => 'lft',   // Default: 'lft'
                // 'rightAttribute' => 'rgt',  // Default: 'rgt'
                // 'depthAttribute' => 'depth', // Default: 'depth'
            ],
        ];
    }

    public function transactions(): array
    {
        return [
            self::SCENARIO_DEFAULT => self::OP_ALL,
        ];
    }
}

declare(strict_types=1);

// Create root node
$root = new Category(['name' => 'Electronics']);
$root->makeRoot();

// Add children
$phones = new Category(['name' => 'Mobile Phones']);
$phones->appendTo($root);

$computers = new Category(['name' => 'Computers']);
$computers->appendTo($root);

// Add grandchildren
$smartphone = new Category(['name' => 'Smartphones']);
$smartphone->appendTo($phones);

$laptop = new Category(['name' => 'Laptops']);
$laptop->appendTo($computers);

declare(strict_types=1);

// Get all descendants of a node
$children = $root->children()->all();

// Get only direct children
$directChildren = $root->children(1)->all();

// Get all ancestors of a node
$parents = $smartphone->parents()->all();

// Get all leaf nodes (nodes without children)
$leaves = $root->leaves()->all();

// Navigate siblings
$nextSibling = $phones->next()->one();
$prevSibling = $computers->prev()->one();

declare(strict_types=1);

// Move as last child
$smartphone->appendTo($computers);

// Move as first child  
$smartphone->prependTo($phones);

// Move as next sibling
$smartphone->insertAfter($laptop);

// Move as previous sibling
$smartphone->insertBefore($laptop);

// Make node a new root (multiple trees only)
$smartphone->makeRoot();

declare(strict_types=1);

// Delete node only (children become children of parent)
$phones->delete();

// Delete node with all descendants
$phones->deleteWithChildren();

declare(strict_types=1);

use yii\db\ActiveQuery;
use yii2\extensions\nestedsets\NestedSetsQueryBehavior;

/**
 * @template T of Category
 *
 * @extends ActiveQuery<T>
 */
class CategoryQuery extends ActiveQuery
{
    public function behaviors(): array
    {
        return [
            'nestedSetsQuery' => NestedSetsQueryBehavior::class,
        ];
    }
}

// In your Category model
/**
 * @phpstan-return CategoryQuery<static>
 */
public static function find(): CategoryQuery
{
    return new CategoryQuery(static::class);
}

declare(strict_types=1);

// Find all root nodes
$roots = Category::find()->roots()->all();

// Find all leaf nodes  
$leaves = Category::find()->leaves()->all();