Node JS get CSV - node.js

Question

I have a project with Node JS in which I am collecting the information of a JSON by http using the node-fetch module.
This is the way I have found to use the node-fetch module with async, if it is possible to improve this function, suggestions are added, I am new to this module.
This is my code where I read the information:
const fetch = require('node-fetch');
(async () => {
try {
const res = await fetch('https://jsonplaceholder.typicode.com/users');
const headerDate = res.headers && res.headers.get('date') ? res.headers.get('date') : 'no response date';
const users = await res.json();
for(user of users) {
console.log(`Got user with id: ${user.id}, name: ${user.name}`);
}
} catch (err) {
console.log(err.message); //can be console.error
}
})();
My problem: how can I extract all the information to a CSV with a limit of lines ?, that is, the CSV has a limit of 10 lines (the limit can vary), if the JSON information occupies 30 lines, 3 CSVs would be created to store all the information. I have added the json-2-csv module, but I don't know how to use it or if this module is necessary or something else is better.

Answer 1

const { Parser } = require("json2csv");
const fetch = require("node-fetch");
const fs = require("fs");
const csvLimit = 3;
const getJson = async () => {
const response = await fetch("https://jsonplaceholder.typicode.com/users");
const responseJson = await response.json();
return responseJson;
};
const jsonToCsv = async () => {
const json = await getJson();
const json2csvParser = new Parser();
let i = 0,
j = 0;
while (j < json.length) {
let csv = [];
let temp = [];
for (j = i * csvLimit; j < (i + 1) * csvLimit; j++) {
temp.push(json[j]);
}
csv.push(json2csvParser.parse(temp));
fs.writeFileSync(`file${(i * csvLimit) / 3}.csv`, csv);
i++;
}
};
jsonToCsv();
If you want only specific fields in the csv file, then you can pass the fields as parameter in this way.
const json2csvParser = new Parser({fields})

Answer 2

I used the flat package to extract the field names from the keys of the first record of the JSON and then used the json-2-csv package to convert from JSON to CSV.
const converter = require("json-2-csv");
const fetch = require("node-fetch");
const fs = require("fs");
const flatten = require('flat');
const maxRecords = 3;
const getJson = async () => {
const response = await fetch("https://jsonplaceholder.typicode.com/users");
const responseJson = await response.json();
return responseJson;
};
const convertToCSV = async () => {
const json = await getJson();
let keys = Object.keys(flatten(json[0]));
let options = {
keys: keys
};
converter.json2csv(json, json2csvCallback, options);
};
let json2csvCallback = function (err, csv) {
if (err) throw err;
const headers = csv.split('\n').slice(0,1);
const records = csv.split('\n').slice(0,);
for(let i=1;i<records.length;i=i+maxRecords) {
let dataOut = headers.concat(records.slice(i, i+3)).join('\n');
let id = Math.floor(i/maxRecords)+1;
fs.writeFileSync('data' + id + '.csv', dataOut)
}
};
convertToCSV();
Here's one of the files opened in Excel.