nestedsetsjs

Nested sets structure with separated items and nodes.

Source here Armasheko Artem / nestedsetsjs.

:evergreen_tree:

Instalation

npm install nestedsetsjs

Usage

var ns        = require('nestedsetsjs')
var NestedSet = ns();

NestedSet.setItem(1, {title: "Root"})
NestedSet.setItem(2, {title: "Type"})
NestedSet.setItem(3, {title: "Type2"})
NestedSet.setItem(4, {title: "Group"})
NestedSet.setItem(5, {title: "Group2"})
NestedSet.setItem(6, {title: "SubGroup"})

var root_node_id = NestedSet.addRoot(1)
var type_node_id = NestedSet.addNode(root_node_id, 2)
var type_node2_id = NestedSet.addNode(root_node_id, 3)
var group_node_id = NestedSet.addNode(type_node_id, 4)
var group_node2_id = NestedSet.addNode(type_node2_id, 5)
var subgroup_node_id = NestedSet.addNode(group_node_id, 6)
var subgroup_node_id2 = NestedSet.addNode(group_node2_id, 6)

console.log(NestedSet.debug())

Methods

setItem(id, data)

Sets data for an item

• id - ID item
• data - Stored data
  Returns Stored data in Data propert

NestedSet.setItem(1, { title: "Root"})

removeItem(id)

Removes an item with its dependent nodes

• id - ID item
  Returns TRUE if item exists or FALSE if not exists

NestedSet.removeItem(1)

addRoot(item_id)

Initializes the Nested Sets structure. Adds a root node and sets an item for it

• item_id - item ID
  Returns node ID = 1

NestedSet.addRoot(1)

addNode(target_node_id, item_id)

Adds a new node to the specified parent node and sets an item for it

• target_node_id - parent node ID
• item_id - item ID
  Returns node ID

NestedSet.addNode(1, 1)

getNode(node_id, asCopy)

Gets a node by ID

• node_id - node ID
• asCopy - true (will return a copy of the object) / false or undefined (will return the object itself)
  Returns node object

NestedSet.getNode(1)

removeNode(node_id)

Removes a node by its ID

• node_id - node ID
  Returns new Structure

NestedSet.removeNode(1)

getNodes ()

Returns all nodes (Structure property)

removeNodes()

Removes all nodes (items are not destroyed)

getParent(node_id)

Returns the first parent for the node

• node_id - node ID

NestedSet.getParent(5)

getParents(node_id)

Returns all parents of the node

• node_id - node ID

NestedSet.getParents(5)

getChilds(node_id, depth)

Returns nested nodes in a node

• node_id - node ID
• depth - nesting depth

NestedSet.getChilds(1, 1)

getBranch(node_id)

Returns the entire branch that contains the node

• node_id - node ID

NestedSet.getBranch(5)

getTree()

Returns the entire structure (nodes and items)

clearAll()

Removes all items and all nodes

isRoot(node_id)

Checks if a node is root

• node_id - node ID

isBranch(node_id)

Checks if a node is a parent

• node_id - node ID

isLeaf(node_id)

Checks if a node is the end of a branch

• node_id - node ID

getMaxRightKey

Returns MAX right key in the tree

getMaxLeftKey

Returns MAX left key in the tree

getCountNodes

Returns count nodes of tree

checkTree()

Checks a tree according to three rules

1. The left node key is always less than the right key
2. The remainder of the division of the difference between the right and left keys must be 0
3. The remainder of dividing the difference between the left key and the nesting depth + 2 must be 0

debug()

Displays information about nodes and items

Properties

• Data (Items)
• Structure (Nodes)

Structure

[
  {
    _id: 1, // ID node
    lkey: 1, // left key
    rkey: 14, // right key
    depth: 0, // depth
    childs: 2, // count childs
    parent_id: 0, // ID parent node
    item_id: 1, // ID item from property Data
    data: { title: 'Root' } // item with ID item_id from property Data
  },
  ...
]

Returns this scheme for methods

• getParent
• getParents
• getChilds
• getBranch
• getTree

Tests

npm install
npm test

ESLint

npm install
npx eslint ./src/nestedsets.js
npx eslint ./test/test.js