correios.js

var http = require('http');

var parseTrack = function (data) {
  var trackLines = data.replace(/[\r\n]/g, '').replace(/<\/tr>/gi, '</tr>\n').match(/<tr.*?>(.*)<\/tr>/gi);
  trackLines.shift();
  var parsed = [], parts = [];
  var length = trackLines.length;
  var details, date, track;

  for (;length--;) {
    parts = trackLines[length].split(/<.*?>/).filter(function (v) { return v !== '' });
    
    if (parts.length === 1) {
      details = parts[0].trim();
    } else {
      date = parts[0].replace(/(\d{2})\/(\d{2})\/(\d{4})(\s+?.*?)/, '$3-$2-$1$4');
      track = {
        date: new Date(date),
        local: parts[1].toLowerCase().trim(),
        status: parts[2].trim()
      };
      if (details) track.details = details;
      parsed.push(track);
      details = null;
    }

  }

  return parsed.reverse();
};

var track = module.exports = function (objectId, callback) {
  var buffer;

  var options = {
    hostname: 'websro.correios.com.br',
    path: '/sro_bin/txect01$.QueryList?P_LINGUA=001&P_TIPO=001&P_COD_UNI=' + objectId
  };

  var req = http.request(options, function (res) {
    res.setEncoding('binary');
    
    res.on('data', function (chunk) {
      buffer = chunk.toString('utf8');
    });

    res.on('end', function () {
      var data = parseTrack(buffer);
      callback(null, data);
    });
  });

  req.on('error', function (e) {
    callback(e);
  });

  req.end();
};

// try it, call node correios.js TE123456789BR
// track(process.argv[2], function (err, data) {
//   console.log(data);
// })