row-to-tree

Converts an array of objects into a tree structure

Why?

When you make a SQL request, you often get an array of rows, each of them being linked to another one in a parent/child relation. And you may want to use this array to display a tree, for example in a Vuetify component.

This module helps you convert the original array into an array of parents and child, building the expected tree:

Example

The test file provides an example of what could be done. Suppose you have the following table:

| id | id_parent | name | |:--:|:---------:|:-----------:| | 1 | null | ROOT | | 2 | 1 | LEAF 2 | | 4 | 1 | LEAF SISTER | | 6 | 2 | OTHER LEAF | | 5 | null | NEW ROOT |

You will end up with an array of objects,

How?

Installation

npm install --save row-to-tree

Usage

const { rowToTree } = require('row-to-tree');

const data = [
  { id: 1, id_parent: null, name: "ROOT" },
  { id: 2, id_parent: 1, name: "LEAF 2" },
  { id: 4, id_parent: 1, name: "LEAF SISTER" },
  { id: 6, id_parent: 2, name: "OTHER LEAF" },
  { id: 5, id_parent: null, name: "NEW ROOT" },
];

console.log(rowToTree(data));

You will get this nested array:

[
  {
    id: 1,
    id_parent: null,
    name: "ROOT",
    children: [
      {
        id: 2,
        id_parent: 1,
        name: "LEAF 2",
        children: [
          {
            id: 6,
            id_parent: 2,
            name: "OTHER LEAF",
            children: []
          }
        ]
      },
      {
        id: 4,
        id_parent: 1,
        name: "LEAF SISTER",
        children: []
      }
    ]
  },
  {
    id: 5,
    id_parent: null,
    name: "NEW ROOT",
    children: []
  },
];

API

rowToTree(data, [idKey], [parentKey], [childrenKey])

Convert an array of objects into a tree structure.

• data (Array): the array of objects to convert;
• idKey (String, optional): the name of the key that identifies an object (default: "id");
• parentKey (String, optional): the name of the key that identifies the parent of an object (default: "id_parent");
• childrenKey (String, optional): the name of the key that will contain the children of an object (default: "children").

Returns an array of root objects.

Licence

MIT