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Hosting discord.js bots on repl.it!! [ Works for both discord.js and Eris ]
TheDrone7 (504)

Hosting discord.js bots on repl.it!

This tutorial shows how you can host your discord bots on repl.it if they are built in node.js irrespective of whatever library you used. This tutorial is applicable for all discord.js and Eris bots.

Just to ease things we'll be using the end product of this tutorial.


What we'll be doing?

  1. Creating a web server using the express module.

  2. Using uptimerobot to ping our bot every 30 minutes.

    We do this because our repl goes offline after 1 hour of inactivity. So we keep pinging the repl every 30 minutes, to avoid it being idle for one hour.


Step 1: Setting up the server

Once you have your bot ready for hosting, use the packages tab of repl.it to install the express package.

Next, create a new file, let's name it server.js because it is a server and why not.
Open up this file and import the express package

const express = require('express');

After that, create a new server! Which is as easy as

const server = express();

And we now have a new server as well! Next step would be to create a route, as without a route your server might as well not exist. So here we go: -

server.all('/', (req, res)=>{
    res.send('Your bot is alive!')
})

This will create a new route at '/' which is basically the home page. .all() method creates a new route for handling all types of HTTP requests like GET/POST/PUT etc. The two parameters it takes are 1) the route and 2) The callback, which in turn takes 2 - 3 parameters ( We use the 2 parameter alternative ) i.e. the HTTP request and the HTTP response.

res.send('Your bot is alive') tells that the server has to return a string saying your bot is alive.

Now that we have our server ready, we'll create a function that starts the server,

function keepAlive(){
    server.listen(3000, ()=>{console.log("Server is Ready!")});
}

The server.listen() is a function that starts the server and takes in multiple arguments.

  1. PORT : the port which listens for the request. (Default for node.js is 3000 so we stick with it)
  2. CALLBACK : the function which takes place when the server is ready for handling requests.

And that's it! Now we will export the keepAlive() function since that's all we really need.

module.exports = keepAlive;

And we're done!

Run your bot, you should see something similar to this: -

  1. If you see this message then you've successfully created a server and the bot as well, if you don't see this, you must have messed something up, go back and make sure everything is right :P.
  2. This is the link which we will ping every 30 minutes to keep the repl alive.

Step 2: Combining the bot and server

Now that our server and bot are both ready, we need to combine the both to bring out the desired outcome. For that, open up your index.js file or whichever file has discordClient.login(TOKEN) method, and import the server.js file. ( I have kept the both in the same directory to keep things simple)

const keepAlive = require('./server');

And just before logging in to your bot use the keepAlive() function.

keepAlive();
// Login the bot
client.login("TOKEN GOES HERE")

and we're done combining the two as well!


Step 3: Setting up UPTIMEROBOT

  1. Visit this link and register a new account ( or login to your old one if you already have one ) just like any other website. ( It is free and safe of course )

  2. Click on the New Monitor button.

  3. It will open up a form, fill it as specified below: -
    Monitor Type : Set it to HTTP(s).
    Friendly Name : Set it to whatever you like. Although, I recommend you name it after your bot.
    URL or IP : Copy your server link and paste it here.
    Monitoring Interval : Anything between 5 minutes to 45 minutes is fine, 30 minutes is recommended
    "Alert Contacts To Notify" : Make sure to select yourself here. It will enable you to get notified whenever your bot goes offline via email.

    and finally click Create Monitor .


Now you're bot will stay online for as long as it can.

( Repl it being just another host, won't be able to host it 24/7 so it will have a downtime of a few minutes within every 24 hours.)

And you're done!

Please upvote if you found this useful!

Also, comment down below if there's something you would like to share or ask.

And finally, thanks for reading it!


Commentshotnewtop
1
[deleted]

if you would like to stop the bot instance you may add client.destroy() line to your code under your message section for example stop so that if you message the bot with stop it would logout (you have to wait till it shows). make sure you put condition like when id = your id otherwise everybody will be able to logout the bot

1
jamppunet (0)

Great tutorial and it seems to be working too :D But what about changing the bot. Do I have control somewhere in repl.it to stop the server, so I could get my new version live?

1
TheDrone7 (504)

@jamppunet there's not a way to stop the server currently, you can always restart the server. A quick way to kill the process would be to deliberately write a line of wrong code and then restart which will end up not running because of the error. You can also stop uptimerobot and wait for 1 hour.

1
jamppunet (0)

@TheDrone7 thanks mate! It seems like I can't run the code while the server is up, since the port is already in use :D

Error: listen EADDRINUSE: address already in use :::3000

But I'll just pause the robot and wait for a while - it's totally ok. This method Rocks - creating a bot in Repl.it makes finally some sense!

1
TheDrone7 (504)

@jamppunet try modifying the server.listen line to this

server.listen(); with nothing between the parantheses.

1
jamppunet (0)

@TheDrone7 You're the man! This way I can develop the bot, even when it's running. It doubles everything up in Discord thou, but that's expected, since there are several instances running at the moment - one on repl.it browser, another one on the server and there is a mysterious third one - probably the server version on repl.it UI.

I'll just close the browser and leave some time for it and it will reset the extras. But thanks for the tips!

I think rest of you using this do the following when developing your bot:
1) pause uptimerobot monitor
2) comment out the server.listen line in the server.js by adding // in front of the line, like this
//server.listen(3000, ()=>{console.log("Server is Ready!")});

and you can still run your code. In Discord you will be getting several replies until the old server version that uptime robot was keeping up dies, but other than that, this is perfect!

When you are ready to go online and keep it up, just remove the // from the server.listen and run it + activate the uptimerobot

1
TheDrone7 (504)

@jamppunet although what you're facing is a repl.it bug. @amasad might wanna look into it. So you should only use the same port to avoid creating multiple instances. But till it's fixed you can do what you're currently doing.

1
jamppunet (0)

@TheDrone7 I haven't changed the ports, it's been 3000 all the time. But there is probably some kind of bug, since it replicates the bot instance...

1
TheDrone7 (504)

@jamppunet using server.listen() without specifying the port creates a new server on whichever port is available. So if you use that then it'll create multiple instances. It's an issue with bring unable to properly kill processes.

1
jamppunet (0)

@TheDrone7 Oh damn ;) Well luckily I just commented the line totally out, so it doesn't listen to anything :D

1
TheDrone7 (504)

@jamppunet ok so basically you're not creating a server for keeping your but up and just running the bot temporarily. It would still create multiple instances because when you click restart it is not killing the earlier process and starting a new one. Although repls automatically die after one hour of inactivity. It should kill the process instantly.

1
jamppunet (0)

Ok @TheDrone7 ,
TBH I'm not running it temporarily, but I was doing a test for the keepAlive feature. I need to add some logic to the bot so I need to edit it and that's why I sent the question in the first place.

Thanks to you, that's sorted out now - so when I have my code ready I can set it on as permanent bot!

I started thinking... If I comment out the keep alive call from the main index, then it doesn't create the server at all - even thou the server is included into the project?

1
noah427 (3)

where is the tutorial for building the actual bot?

1
TheDrone7 (504)

@noah427 the link is there in the introduction the text of this tutorial is the link.