Is it possible to destructure a nested object without knowing the key of the parent?

Question

I was wondering if it is possible to destructure a nested object without knowing the key of the parent object?

The reason to do this is that mongoose validation errors returns an object in the errors key and each entry of this object is another object where the key is the name of the field that has an error.

const data = {
  name: {
    path: 'name',
    name: 'The error message'
  },
  email: {
    path: 'email',
    name: 'Another error message'
  }
}

So the result can be something like

{
  name: 'The error message',
  email: 'Another error message'
}

Is it possible that the unique way to do this is using for in loop and perform the destructuring assignment inside of it?

let message = {}
for (var k in data) {
  var { path, name } = data[k]
  message[path] = name
}

You can't destructure through a loop, though you *can* retrieve the value without destructuring. What exactly varies in the code you posted, and what's the desired output? — CertainPerformance, Feb 19 '19 at 08:33
@CertainPerformance, then this is the unique way to do it, right? So, probably it is better to avoid destructuring and do `message[data[k][path] = data[k][name]`? — abaracedo, Feb 19 '19 at 10:05
That looks kinda confusing, I prefer your current method with destructuring (just change to bracket notation) — CertainPerformance, Feb 19 '19 at 10:07

Nina Scholz · Answer 1 · 2019-02-19T10:07:11.223

1

You could take the values and map new objects. Then assign all objects to a single object.

const
    data = { name: { path: 'name', name: 'The error message' }, email: { path: 'email', name: 'Another error message' } }
    result = Object.assign({}, ...Object
        .values(data)
        .map(({ path, name }) => ({ [path]: name }))
    );

console.log(result);

edited Feb 19 '19 at 10:07

answered Feb 19 '19 at 08:34

Nina Scholz

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no enough description for coding process – ﾃﾞﾋﾞｯﾄ Feb 19 '19 at 08:53
I have updated the description with the output I would like to achieve. – abaracedo Feb 19 '19 at 09:58

score 0 · Answer 2 · answered Feb 19 '19 at 08:35

0

Use Object.values like so:

const data = { name: { path: 'name', name: 'The error message' } };

const { path, name } = Object.values(data)[0];

console.log(path);
console.log(name);

answered Feb 19 '19 at 08:35

Jack Bashford

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score 0 · Answer 3 · answered Feb 19 '19 at 08:38

0

const data = {
  name: {
    path: 'name',
    name: 'The error message'
  }
}

const {path, name} = Object.values(data)[0];

console.log(path, name);

answered Feb 19 '19 at 08:38

random

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score 0 · Answer 4 · answered Feb 19 '19 at 08:50

Yes you can do inside for in by taking the key and accessing the value and destructure it

const data = {
  name: {
    path: 'name',
    name: 'The error message'
  }
}

for(let key in data){
  let { path, name } = data[key]
  console.log('name --->',name)
  console.log('path --->',path)
}

Is it possible to destructure a nested object without knowing the key of the parent?

4 Answers4