Simple Tree Utils

Simple Tree Utils is the library to convert and manipulate with tree-like structures. Library provides converter from an array of objects to trees like structure and vice versa, and also methods to manipulate that tree and/or search in that tree.

It is created because I needed to convert the array of objects into a tree to visualize in Angular tree component. Surely there are plenty of similar libraries, but I think all of them work with their own models/classes, I needed to use my own data without no extra instantiating, or adding extra methods/properties into the working model.

Instalation

Install library using npm npm install simple-tree-utils --save and import main class into your code base import {TreeUtils} from 'simple-tree-utils'; .

Usage

First instantiate class with config, or without config.

const treeUtils = new TreeUtils(); // without config, default values are used (id as idProp, parentId as parentIdProp, children as childrenProp)
const treeUtils2 = new TreeUtils({
  idProp: 'id', // the key of a unique identifier for an object (source object)
  parentIdProp: 'parentId', // the key of a unique parent identifier (source object)
  childrenProp: 'children', // the key, where child nodes are stored (destination object tree)
});

After instantiation, you can use tree utils. You can convert the array of the following objects into a tree using list2Tree method as following

const items = [
  {id: 1, parentId: null, name: 'Node 1'},
  {id: 2, parentId: null, name: 'Node 2'},
  {id: 3, parentId: 1, name: 'Node 3'},
  {id: 4, parentId: 1, name: 'Node 4'},
  {id: 5, parentId: 2, name: 'Node 5'},
  {id: 6, parentId: 3, name: 'Node 6'},
];
const output = treeUtils.list2Tree(items);

then the output of lift2Tree will be

const tree = [
  {
    id: 1, parentId: null, name: 'Node 1', children: [
      {
        id: 3, parentId: 1, name: 'Node 3', children: [
          {id: 6, parentId: 3, name: 'Node 6', children: []},
        ]
      },
      {id: 4, parentId: 1, name: 'Node 4', children: []},
    ]
  },
  {
    id: 2, parentId: null, name: 'Node 2', children: [
      {id: 5, parentId: 2, name: 'Node 5', children: []},
    ]
  },
];

When you got a structure like the above, you can use all the following methods:

Name	Desription	Signature
addNode	Method to add new node to tree (mutable operation!)	addNode(tree: any[], parentId: any, childData: any): void
deleteNode	Method to delete node in tree by given id (mutable operation!)	deleteNode(tree: any[], id: any): any
editNode	Method to update node by id with given data in tree (mutable operation!)	editNode(tree: any[], id: any, data: any): void
findAllChildrenNodes	Method to find all children nodes of given node in tree structure	findAllChildrenNodes(tree: any[], id: any): any[]
findAllParentNodes	Method to find all parents of given node in tree structure	findAllParentNodes(tree: any[], id: any): any[]
findAllTreeNodes	Method to find all nodes in tree structure by given callback function	findAllTreeNodes(tree: any[], fn: ((item: any) => boolean)): any
findNodeParent	Method to find parent of given node in tree structure	findNodeParent(tree: any[], id: any, parent?: any): any
findTreeNode	Method to find node in tree structure by given callback function	findTreeNode(tree: any[], fn: ((item: any) => boolean)): any
findTreeNodeById	Method to find node in tree structure by given id	findTreeNodeById(tree: any[], id: any): any

For example, we can find node by giving callback

const node = treeUtils.findTreeNode(tree, item => item.id === 2);

If you need a list again, you can convert the tree back to a list using treeUtils.tree2List method

treeUtils.tree2List(tree);

Documentation

For more details and complete documentation check: https://simple-tree-utils.netlify.app/

Usage in browser

You can also use this library in the browser without compiling using jsDelivr. Import script into HTML file, and you can access classes through the global treeUtils object.

<script src="https://cdn.jsdelivr.net/npm/simple-tree-utils@1/dist/browser-bundle.min.js"></script>
<script>
    const utils = new treeUtils.TreeUtils();
    const tree = utils.list2Tree(items);
</script>

License

MIT