How to build a reddit to twitter bot

First of all what will be this bot doing actually?

Ans. This bot will tweet any new post from a particular subreddit to your Twitter bot account. In my case it will be tweeting any new posts from /r/anime.

Can I have a look at the finished product?

Ans. Here you go

So what do I actually need to create the bot?

Ans.

• Some basic programming knowledge and how to run a terminal.
• You will need to install a few pieces of software.
• Get the gist of the code to modify it and make your own bot.

So let’s begin.

Installing node js

• First of all go to this link and download Node.js, clicking the installer for your OS.
• Now run the setup and install it. Make sure you check the option to include it in PATH.
• Next open up your terminal and type this:

$ node

• If your ‘$’ prompt changes into a ‘>’ prompt then you did everything correctly up to this point.

Creating node package

Now it’s time to start coding.

First of all go to the folder where you want to make your bot (create your node package). Then run:

$ npm init

Now it will ask you for a few pieces of information. Here’s an example:

name: twitter bot
version: (0.0.0) 1.0.0
description: My package description goes here.
entry point: bot.js
test command:
git repository: 
keywords: bot twitter reddit
author: Debakar Roy
license: (ISC)

This will create a json file named package.json. You can edit it as you like in future.

[NOTE: What is json? Ans. JSON, or JavaScript Object Notation, is a minimal, readable format for structuring data. It is used primarily to transmit data between a server and web application, as an alternative to XML.]

Installing dependency packages

Now it’s time to install a few Node packages. You can head over to npmjs.com to look up the packages you need.

[NOTE: What is npm? Ans. npm makes it easy for JavaScript developers to share and reuse code, and it makes it easy to update the code that you’re sharing. To be honest these are premade packages which let you use different APIs.]

Packages we need:

• twit [To talk with twitter.]
• reddit-snooper [To talk to reddit.]
• goo.gl [To create short link.]

To install a package use this code:

$ npm install twit --save
$ npm install reddit-snooper --save
$ npm install goo.gl --save

It might give you some warnings. That’s only because you didn’t fill in the package.json fields. You don’t need to worry about that :).

I would highly recommend you go through the documentation for each node package to get a basic knowledge of how to use the packages.

Creating bot file

Now create a file named bot.js and copy all this code into it. For simplicity I have added a few comments so you can understand what the snippets are doing.

//Bot start message
console.log('Starting bot.');

//nmp modules
var Twit = require('twit');
var Snooper = require('reddit-snooper')
var googl = require('goo.gl');

//Authenticate twitter
var T = new Twit({
  consumer_key:         'Consumer key',
  consumer_secret:      'Consumer Secret',
  access_token:         'Access Token',
  access_token_secret:  'Access Token Secret',
  timeout_ms:           60*1000,  // optional HTTP request timeout to apply to all requests. 
});

//Authenticate reddit
snooper = new Snooper({
			
			// credential information is not needed for snooper.watcher 
            username: 'reddit_username',
            password: 'reddit password',
            app_id: 'reddit api app id',
            api_secret: 'reddit api secret',
            user_agent: 'OPTIONAL user agent for your bot',
 
            automatic_retries: true, // automatically handles condition when reddit says 'you are doing this too much' 
            api_requests_per_minuite: 60 // api requests will be spread out in order to play nicely with Reddit 
        });

googl.setKey('Your Google API key');
googl.getKey();

var tweet_text;

//reddit new post search
snooper.watcher.getPostWatcher('subreddit name') 
    .on('post', function(post) {
		var shortlink = 'www.reddit.com/' + post.data.permalink;
		var shortposturl = post.data.url;
		console.log(shortlink)
		
		//Create short url
		googl.shorten(shortlink)
			.then(function (shortUrl) {
				console.log(shortUrl);
				shortlink = shortUrl;
			})
			.catch(function (err) {
				console.error(err.message);
			});
					
		googl.shorten(shortposturl)
			.then(function (shortUrl) {
				console.log(shortUrl);
				shortposturl = shortUrl;
			})
			.catch(function (err) {
				console.error(err.message);
			});
		
		//Tweet Generator
		var tweet_title = 'Title: ' + (post.data.title);
		if((post.data.title).length>=70){
			tweet_title = 'Title: ' + (post.data.title).substring(0, 70) + '...';
		}
		var tweet_url ='\nUrl: ' + shortposturl;
		var tweet_discuss =  '\nDiscussion: '+ shortlink;
		
		//Tweet
		tweet_text = tweet_title + tweet_discuss + tweet_url ;
		
		//Print tweet to console
		console.log(tweet_text)
		
		tweet_mytext(tweet_text);
    })
    .on('error', console.error)

//Function to post the tweet
function tweet_mytext(tweet_text){
	var tweet = {
			status: tweet_text
	}

	console.log('\n' + tweet.status)
	T.post('statuses/update', tweet, tweeted);

	function tweeted(err, data, response) {
			if (err) {
				console.log("Didn't tweet :(.");
			} else {
				console.log("It worked! Tweeted!!");
			}
	}
}

How to get credential needed for setting up bot

So there are several questions you will ask:

How to obtain consumer_key, consumer_secret, and other twitter credentials.

Ans.

• For this go to apps.twitter.com. Make sure you are signed in to your Twitter bot account. Twitter will not let you create an app until you have verified your account.
• You can use your real phone number or Twilio or any cloud-communication-based SMS service to finish verifying your account.
• Now click on Create New App. Fill in the name, description, and website. Tick Yes, I have read and agree to the Twitter Developer Agreement.
• Go to Keys and Access Tokens and you will find your consumer_key and consumer_secret there. To generate access_token and access_token_secret click on create my access token under Token Actions.

How to obtain api_secret, app_id, and other reddit credentials.   Ans. Steps you need to follow are in the node package description:

• Create (or log into) a reddit account
• Navigate to the authorized applications console
• Select ‘create another app…’ at the bottom
• Fill in the name, description and click on ‘script’, put in anything for the redirect uri, its not needed and you can change it later if you want to
• Copy down the ‘secret’ that is your apisecret, the 14 character string by the name of your app is your appid
• Use these values and your credentials to configure the snooper

Now how to obtain the Google API key.

Ans.

• Visit https://console.developers.google.com/cloud-resource-manager and create a new project
• Search and turn on URL Shortener API
• Go to Credentials on the left-hand side, click on create credentials and then API key. That is your API key.

Pasting all these credentials into bot.js will let you use the bot.

Now head to the terminal and type:

$ node bot.js

Conclusion

Congratulation, you just made a bot which lets you fetch any new post from a particular subreddit and tweet it using your Twitter bot account.

NOTE: Please follow Twitter, Google, and Reddit rules to avoid getting banned. This post is only meant for educational purposes. I will not take any blame if you get into trouble in any way.

Next tutorial will be how to host this bot on Heroku, so that you can let it run even after you turn off your computer. Until then stay well and thank you for reading.