JSFiddle - React, Tailwind, and code Playground
JavaScript
var str = 'id nm lat lon countryCode\n819827 Razvilka 55.591667 37.740833 RU\n524901 Moscow 55.752220 37.615555 RU\n1271881 Firozpur 27.799999 76.949997 IN';
var cells = str.split('\n').map(function (el) { return el.split(/\s+/); });
var headings = cells.shift();
var out = cells.map(function (el) {
var obj = {};
for (var i = 0, l = el.length; i < l; i++) {
obj[headings[i]] = isNaN(Number(el[i])) ? el[i] : +el[i];
}
return obj;
});
console.log(JSON.stringify(out, null, 2));