js-flatten-object

JavaScript flattenObject function that traverses and flattens any object

How it works

This recursive function accepts two arguments: objectToFlat and flatObject and returns flatObject containing key/value pairs from objectToFlat flattened to a single level object. This function traverses nested objects to the lowest level until there are no more nested objects within object.

Caveats

Parent key/value objects will be lost if there's any following child object with the same key name. Remember? We can't have object with duplicate key names!
Key names from parent objects will be lost forever. There's nowhere to go!
Nested objects containing arrays will be lost

Result example

Let's process this multi-level object and get it flattened:

let objectToFlat = {
  title: "Terminator 2",
  writtenBy: [
    "James Cameron", 
    "William Wisher Jr."
  ],
  year: 1991,
  aired: true,
  cast: {
    mainRoles: {
      "Arnold Schwarzenegger": "The Terminator",
      "Linda Hamilton": "Sarah Connor"
    },
    otherRoles: {
      "Ron Young": "Pool Cue Biker",
      "Mike Muscat": "Moshier",
      evenMoreRoles: {
        "Abdul Salaam El Razzac": "Gibbons"
      }
    }
  },
}

with the result being:

{
  "title": "Terminator 2",
  "year": 1991,
  "aired": true,
  "Arnold Schwarzenegger": "The Terminator",
  "Linda Hamilton": "Sarah Connor",
  "Ron Young": "Pool Cue Biker",
  "Mike Muscat": "Moshier",
  "Abdul Salaam El Razzac": "Gibbons"
}

Usage example

const flattenObject = require('./js-flatten-object)

let flatObject = flattenObject(objectToFlat, {})

Syntax

flattenObject(objectToFlat, flatObject)

Parameters

objectToFlat - object to flat

flatObject - object where flattened key/value pairs will be stored

Return value

flatObject containing flattened objectToFlat object

pawelotto/js-flatten-object