app.js

var TwitterPackage = require('twitter');

// twitter's secret keys are hidden with .gitignore
var apikeys = require('./apikeys.js');

// getTwitterSecret() returns apikeys array
var Twitter = new TwitterPackage(apikeys.getTwitterSecret());
console.log("SUCCESS: Jennifer initiated and ready to make query with Twitter API.")

console.log("INFO: Tracking tweets with @sntshk, and greeting them with custom message.")

// self explanatory code below
Twitter.stream('statuses/filter', {track: '@sntshk'}, function(stream) {
  stream.on('data', function(tweet) {
    // tweet object created above have many methods,
    // see: https://dev.twitter.com/overview/api/tweets
    // even we can go up to user: https://dev.twitter.com/overview/api/users
    
    var txt = tweet.text;
    var username = tweet.user.screen_name;
    var real_name = tweet.user.name;
    var tweet_id = tweet.id_str;
    
    console.log('===========STREAM STARTS===========');
    // everytime someone mentions @sntshk, log to console
    console.log('-----------------------------------\n@' + username + " says: " + txt);
    console.log("TID: " + tweet_id + ". TSTAMP: " + tweet.created_at + '\n-----------------------------------');
    
    // And also reply to them.
    // TODO: Can't write @sntshk in tweet. It goes in loop.
    var reply = "Hi @" + username +", you've mentioned Santosh. I'm his personal assistant Jennifer. I am not very useful at the moment.";
    
    // parameters that twitter accepts, along with text
    var params = {
        status : reply,
        in_reply_to_status_id_str : tweet_id,
        in_reply_to_screen_name : username,
        lat: 28.6289143,
        long: 77.2065322,
    };
    
    // post the composed tweet..
    Twitter.post('statuses/update', params, function(err, data, response) {
        if (err) {
            console.log("Error is: " + err);
        } else {
            console.log('Tweeted: ' + params.status);
        }
    })
  });

  stream.on('error', function(error) {
    console.log(error);
  });
});