walk-object

Walks an object's keys, calling a function when each node is reached. Walk can be performed synchronously or asynchronously.

Synchronous example

const { walkObject } = require('walk-object')

const obj = {
  order: {
    number: 123,
    customer: {
      name: 'John Smith'
    },
    items: [
      {
        sku: 456,
        description: 'shirt'
      },
      {
        sku: 789,
        description: 'pants'
      }
    ]
  },
}

walkObject(obj, ({ value, location, isLeaf }) => {
  if (isLeaf) console.log(value, location)
})

//
123, ['order', 'number']
'John Smith', ['order', 'customer', 'name']
456, ['order', 'customer', 'items', 0, 'sku']
'shirt', ['order', 'customer', 'items', 0, 'description']
789, ['order', 'customer', 'items', 1, 'sku']
'pants', ['order', 'customer', 'items', 1, 'description']

Async example

const { walkObjectAsync } = require('walk-object')

const obj = {
  order: {
    number: 123,
    customer: {
      name: 'John Smith'
    },
    items: [
      {
        sku: 456,
        description: 'shirt'
      },
      {
        sku: 789,
        description: 'pants'
      }
    ]
  },
}

const vals = []

// Simulate some async function...
async function logValues({ value, location, isLeaf }) {
  return new Promise((resolve) => {
    setTimeout(() => {
      if (isLeaf) {
        asyncVals.push({value, location})
        resolve()
      }
    }, 250)
  })
}

walkObjectAsync(obj, logValues)

console.log(vals)

//
[
  {
    value: 123,
    location: ['order', 'number']
  },
  {
    value: 'John Smith',
    location: ['order', 'customer', 'name']
  },
  {
    value: 456,
    location: ['order', 'customer', 'items', 0, 'sku']
  },
  {
    value: 'shirt',
    location: ['order', 'customer', 'items', 0, 'description']
  },
  {
    value: 789,
    location: ['order', 'customer', 'items', 1, 'sku']
  }
    value: 'pants',
    location: ['order', 'customer', 'items', 1, 'description']
  }
]

Installation

npm install --save walk-object

API

walkObject(root, fn) and walkObjectAsync(root, fn)

param: {object} root - The object to walk.

param: {function} fn - Function to call on each node. For walkObjectAsync, fn must be an async function (i.e. a function that returns a promise).

The function will be passed an object with the following properties:

value: {any} - The value of the current node.

key: {string} - The key for the current node. If node is an element of an array key will be in the format of key:index. See walk-object.test.js for an example.

location: {array} - The full location of the current node (see examples above).

isLeaf: {boolean} - Whether or not the node is a leaf.

Test

npm test

License

MIT