how to remove null, {}, [] from json object in node js? - node.js

Question

The json format is like that:
[
[
{},
{
"Country": "Japan",
"cityName": "tokyo",
"onto": [
{
"level1": "one",
"articles": [
null,
{
"id": "114506604",
"name": "bunya3",
"abc": [
{
"filename": "attachmentsfilename3",
"size": 3
}
],
"image": {}
}
]
}
]
}
],
[
{}
]
]
We can see few null, {} and [{}]. How can we remove it ? By the way I am using node js. I have tried by nnjson
nnjson.removeNull(obj_summary);
But not works object without key.

Answer 1

If we assume that your data is always going to be an array, we can map over it and remove empty arrays and objects from the first level:
const data = [
[
{},
{
Country: 'Japan',
cityName: 'tokyo',
onto: [
{
level1: 'one',
articles: [
null,
{
id: '114506604',
name: 'bunya3',
abc: [
{
filename: 'attachmentsfilename3',
size: 3
}
],
image: {}
}
]
}
]
}
],
[{}]
]
function clean(input) {
return input
.map(item => {
// remove empty arrays
if (Array.isArray(item) && item.length === 0) {
return null
}
// Remove empty objects
if (item instanceof Object && Object.keys(item).length === 0) {
return null
}
return item
})
.filter(item => item)
}
console.log(clean(data))

Answer 2

I found the solution.
To remove null I used:
let retSummary = JSON.parse(stringifySummary, (k, v) => Array.isArray(v) ?
v.filter(e => e !== null) : v);
To remove {} I used
var newArray = parObj.filter(value => Object.keys(value).length !== 0);