Objectifying a CSV with streams!

app.js

var objectify = require('./objectify'),
  fs = require('fs');
  
var source = fs.createReadStream(__dirname+'/file.csv');

var objects = source.pipe(objectify);

objects.on('data', function(object) {
  // do something with the object
});

objects.on('end', function() {
  // done reading objects from the CSV
});

objectify.js

var stream = require('stream');

var objectify = new stream.Transform({
  objectMode: true
});

objectify._buffer = '';

objectify._transform = function (data, encoding, cb) {
  this._buffer += data;
  var lines = this._buffer.split('\n');
  while (lines.length > 1) {
    this.push(objection(lines.shift()));
  }
  this._buffer = lines.join('\n');
  cb();
};

module.exports = objectify;

// This is a custom parsing function to build the object
function objection(line) {
  var row = line.split(',');
  return {
    individualId: row[0],
    logDate: new Date(row[1]),
    actionDate: (row[2]) ? new Date(row[2]) : null,
    key: row[3],
    value: (row[4]) ? row[4] : null
  };
}

function isDate(date) {
  return date instanceof Date && !isNaN(date.valueOf());
}