Adding nested arrays in JSON file using node.js

Newbie123 :

I am fairly new to Javascript and nodejs. I would like a JSON file (results.json) that takes the format of something similar to this:

Starts off as:

{
  "name":"John",
  "task":[]
}

then eventually becomes something like this with nested arrays:

{
  "name":"John",
  "task":[ ["task1","task2"], ["task3", "task4"] ]
}

I want to push to the "task" array a new list of tasks (always of size 2) everytime something is done (in my case when a form is submitted with a button-press).

So for example, after another "action", the JSON file will look something like this:

{
  "name":"John",
  "task":[ ["task1","task2"], ["task3", "task4"] , ["task5", "task6"] ]
}

NOTE: "task(1,2,...,6) was just used as an example, these will be other strings corresponding to the form submission.

This is what I have so far in my server-side file:

var fs = require('fs')

app.post("/addtask", function(req, res) {
fs.readFile('results.json', function (err, data) {
    var json = JSON.parse(data)
    var newTask1 = req.body.newtask1
    var newTask2 = req.body.newtask2

    //WHAT DO I PUT HERE

    fs.writeFile("results.json", JSON.stringify(json))
})
});

Please do correct me if my syntax is wrong or if my idea of how a JSON file works is wrong.

Sunil Lama :

Just push the data as an array

var resObj= {
  "name":"John",
  "task":[]
}

var newTask1 = "task1";
var newTask2 = "task2";

resObj.task.push([newTask1,newTask2]);

console.log(resObj);