How to send big set of JSON data from nodejs?

Question

I'm trying to make a response that sends a big data of JSON. So JSON.stringify() seems not to work because let's say I have an object:

const student = {
  somevar: 15,
  anothervar: 21,
  setofdata: Map(15) {
    1 => {
      somevar: 31, 
      anothervar: 45
    }
    2... 15
  }
}

So what happens when I convert it to string will be like this: {'somevar': '15', 'anothervar': '21', 'setofdata': {}}

Now when I parse it back, it seems like he doesn't know all about inside the set of data. What module should I download to achieve this? I tried LJSON but it didn't work out.

score 1 · Answer 1 · answered Jan 30 '21 at 15:27

In this particular case, student contains a Map object, which is stringified to "{}".

A quick work-around would be to convert it to a flat object first:

const student = {
  somevar: 15,
  anothervar: 21,
  setofdata: new Map([[0, 'hello'], [1, 'world']])
}

const normalized = {...student, setofdata: Object.fromEntries(student.setofdata)};

console.log(JSON.stringify(normalized))

If you wish to use a more generic and profound solution, take a looke here:

How do you JSON.stringify an ES6 Map?

It suggests a way to customize the serialization, specifically for maps (can be also implemented on special js values like NaN, Infinity and others)

How to send big set of JSON data from nodejs?

1 Answers1