Discord Bot using AWS Lambda - aws-lambda

Question

I am trying to build a discord bot and was wonderig if i can use AWS lambda for it. So far i haven't seen someone did it already so was confuse if its possible or not. Specially when lambda's aren't active all the time.

Answer 1

ancient question, but this is now possible, since discord starting providing outgoing webhooks a few weeks ago
(shameless self plug) i wrote a bit of a guide here

Answer 2

This is now possible but following an integration approach rather than the traditional bot approach. This differs as detailed below.
The slash commands official documentation gives us this info:
Slash Commands and Interactions bring something entirely new to the table: the ability to interact with an application without needing a bot user in the guild.
You are now able to receive interaction events via your preferred URL endpoint such as an AWS Lamba function, Firebase Cloud function, Azure Cloud function, etc.
This official receiving an interaction section tells us:
In your application in the Developer Portal, there is a field on the main page called "Interactions Endpoint URL". If you want to receive Interactions via outgoing webhook, you can set your URL in this field.
It is important to remember, though, that the data sent to the endpoint URL for interactions is not the same as running a bot client, in fact they make comment on that here:
In many cases, you may still need a bot user. If you need to receive gateway events, or need to interact with other parts of our API...

Answer 3

In my opinion, although We can post messages by AWS Lambda using Webhook, But we can not receive and process messages using AWS Lambda.
This is because discord does not provide message posting events.

Answer 4

here's a minimal implementation in nodejs that will give you an acceptable Interactions Endpoint URL:
serverless.yml
service: discord
variablesResolutionMode: 20210326
frameworkVersion: '2'
provider:
name: aws
runtime: nodejs14.x
stage: whatever
region: us-east-1
lambdaHashingVersion: 20201221
iam:
role:
name: discord
# https://docs.aws.amazon.com/systems-manager/latest/userguide/sysman-paramstore-access.html
statements:
-
Effect: Allow
Action:
- 'ssm:DescribeParameters'
Resource: '*'
-
Effect: Allow
Action:
- 'ssm:GetParameter'
Resource:
- 'arn:aws:ssm:us-east-1::parameter/discord_token'
- 'arn:aws:ssm:us-east-1::parameter/discord_application_id'
- 'arn:aws:ssm:us-east-1::parameter/discord_public_key'
functions:
interactions:
handler: handler.interactions
environment:
DISCORD_TOKEN: ${ssm:/discord_token}
DISCORD_APPLICATION_ID: ${ssm:/discord_application_id}
DISCORD_PUBLIC_KEY: ${ssm:/discord_public_key}
events:
-
http:
path: interactions
method: post
cors: true
handler.js
'use strict';
const nacl = require('tweetnacl');
module.exports.interactions = async (event) => {
const verified = nacl.sign.detached.verify(
Buffer.from(event.headers['x-signature-timestamp'] + event.body),
Buffer.from(event.headers['x-signature-ed25519'], 'hex'),
Buffer.from(process.env.DISCORD_PUBLIC_KEY, 'hex')
);
const body = JSON.parse(event.body);
const response = {
body: JSON.stringify(
verified
? { type: body.type }
: { error: 'invalid request signature' },
null,
2
),
statusCode: verified
? 200
: 401
};
console.log(JSON.stringify({ event, response }, null, 2));
return response;
};