Tree

Nested Set implementation for PHP.

Features

• NestedSet(MPTT - Modified Pre-order Tree Traversal)
• Support scopes (multiple independent tree in one db table)
• Rebuild broken tree
• Tested with MySQL/MariaDB and PostgreSQL but should work with any database vendor which support transaction
• Supported PDO, Zend Framework 1, Laminas Db, Doctrine 2 DBAL and Doctrine 3 DBAL. It is easy to implement support for any framework
• Support nested transaction
• PHP 7 and PHP 8 support

Dependencies

• This library has no external dependencies. Can work with pure PHP.

Installation

Run following command in terminal

composer require stefano/stefano-tree

Create Tree Adapter

key	type	required	default value	note
tableName	string	yes
idColumnName	string	yes
leftColumnName	string	no	lft
rightColumnName	string	no	rgt
levelColumnName	string	no	level
parentIdColumnName	string	no	parent_id
sequenceName	string	see note		Required for PostgreSQL
scopeColumnName	string	see note		If empty scope support is disabled
dbSelectBuilder	callable	no		see Join table example below

use \StefanoTree\NestedSet;

$options = array(
    'tableName'    => 'tree_traversal',
    'idColumnName' => 'tree_traversal_id',
    // other options
);

$dbAdapter = pure \PDO, Zend1 Db Adapter, Laminas Db Adapter, Doctrine DBAL Connection or any class which implements StefanoTree\NestedSet\Adapter\AdapterInterface interface 

$tree = new NestedSet($options, $dbAdapter);

• You can join table.

$options = array(
    'tableName'       => 'tree_traversal',
    'idColumnName'    => 'tree_traversal_id',
    'dbSelectBuilder' => function() {
         // You can use any "callable" like function or object
         // Select must be without where or order part
         return 'SELECT tree_traversal.*, m.something, ...'
           .' FROM tree_traversal'
           .' LEFT JOIN metadata AS m ON tree_traversal.id=m.tree_id';
     }, 
    // other options
);

$tree = new NestedSet($options, $dbAdapter);

API

Creating nodes

• Create root node

use StefanoTree\Exception\ValidationException;

try {
    $data = array(
        // values
        // id_column_name => uuid 
    );
    
    // create root node.
    $rootNodeId = $tree->createRootNode($data);
    
    // create root node. Second param "$scope" is required only if scope support is enabled.
    $rootNodeId = $tree->createRootNode($data, $scope);    
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}    

• Create new node. You can create new node at 4 different locations.

use StefanoTree\Exception\ValidationException;

try {
    $targetNodeId = 10;
    
    $data = array(
        // values
        // id_column_name => uuid 
    );

    $nodeId = $tree->addNode($targetNodeId, $data, $tree::PLACEMENT_CHILD_TOP);
    $nodeId = $tree->addNode($targetNodeId, $data, $tree::PLACEMENT_CHILD_BOTTOM);
    $nodeId = $tree->addNode($targetNodeId, $data, $tree::PLACEMENT_TOP);
    $nodeId = $tree->addNode($targetNodeId, $data, $tree::PLACEMENT_BOTTOM);
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}    

Update Node

use StefanoTree\Exception\ValidationException;

try {
    $targetNodeId = 10;
    
    $data = array(
        // values
    );
    
    $tree->updateNode($targetNodeId, $data);
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}    

Move node

• You can move node at 4 different locations.

use StefanoTree\Exception\ValidationException;

try {
    $sourceNodeId = 15;
    $targetNodeId = 10;
    
    $tree->moveNode($sourceNodeId, $targetNodeId, $tree::PLACEMENT_CHILD_TOP);
    $tree->moveNode($sourceNodeId, $targetNodeId, $tree::PLACEMENT_CHILD_BOTTOM);
    $tree->moveNode($sourceNodeId, $targetNodeId, $tree::PLACEMENT_TOP);
    $tree->moveNode($sourceNodeId, $targetNodeId, $tree::PLACEMENT_BOTTOM);
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}        

Delete node or branch

use StefanoTree\Exception\ValidationException;

try {
    $nodeId = 15;
    
    $tree->deleteBranch($nodeId);
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}    

Getting nodes

• Get descendants

$nodeId = 15;

// all descendants
$tree->getDescendantsQueryBuilder()
     ->get($nodeId);
     
// all descendants result as nested array
$tree->getDescendantsQueryBuilder()
     ->get($nodeId, true);
     
// only children     
$tree->getDescendantsQueryBuilder()
     ->excludeFirstNLevel(1)
     ->levelLimit(1)
     ->get($nodeId);

// exclude first level($nodeId) from result
$tree->getDescendants()
     ->excludeFirstNLevel(1)
     ->get($nodeId);

// exclude first two levels from result
$tree->getDescendantsQueryBuilder()
     ->excludeFirstNLevel(2)
     ->get($nodeId);

// return first 4 level
$tree->getDescendantsQueryBuilder()
     ->levelLimit(4)
     ->get($nodeId);

// exclude branch from  result
$tree->getDescendantsQueryBuilder()
     ->excludeBranch(22)
     ->get($nodeId);

• Get Ancestors

$nodeId = 15;

// get all
$tree->getAncestorsQueryBuilder()
     ->get($nodeId);
     
// get all as nested array
$tree->getAncestorsQueryBuilder()
     ->get($nodeId, true);

// exclude last node($nodeId) from result
$tree->getAncestorsQueryBuilder()
     ->excludeLastNLevel(1)
     ->get($nodeId);

// exclude first two levels from result
$tree->getAncestorsQueryBuilder()
     ->excludeFirstNLevel(2)
     ->get($nodeId);

Validation and Rebuild broken tree

• Check if tree is valid

use StefanoTree\Exception\ValidationException;

try {
    $satus = $tree->isValid($rootNodeId);
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}

• Rebuild broken tree

use StefanoTree\Exception\ValidationException;

try {
    $tree->rebuild($rootNodeId);
} catch (ValidationException $e) {
    $errorMessage = $e->getMessage();
}

Contributing

Any contributions are welcome. If you find any issue don't hesitate to open a new issue or send a pull request.