Simple AWS ECS status update notifications to Slack webhook

index.js

/*
  Want to know when ECS events happen in Slack? Try this.
  (1) Create a new Slack app with an incoming webhook, save the webhook URL
  (2) Create an SNS topic called something like ECSEvents
  (3) Create a CloudWatch Rule that publishes all ECS events to the topic
  (4) Create a Node.js Lambda that is triggered by the SNS topic
  (5) Add a WEBHOOK_URL environment variable to the Lambda with the webhook URL
  (6) Paste this code into index.js
  (7) Paste the contents of https://unpkg.com/node-fetch/lib/index.js into fetch.js
  (8) Deploy and enjoy
*/

const fetch = require('./fetch')

const RED = '#cd3131'
const YELLOW = '#e5e512'
const GREEN = '#05bc79'
const BLUE = '#2472c8'

exports.handler = async(event) => {
    for (const record of event.Records) {
        const msg = JSON.parse(record.Sns.Message)
        console.log(JSON.stringify(msg)) // For debugging

        const title = msg['detail-type']
        const d = msg.detail
        let color, text, body

        switch (title) {

            case "ECS Deployment State Change":
                color = /COMPLETED/.test(d.eventName) ? GREEN : YELLOW
                text = d.eventName + '\n' +
                    (msg.resources ? msg.resources.join('\n') : '')
                break

            case "ECS Task State Change":
                color = /DELETED|STOPPED/.test(d.lastStatus) ? RED :
                    /RUNNING/.test(d.lastStatus) ? GREEN :
                    YELLOW
                text = [
                    `Cluster: ${d.clusterArn.replace(/^.*\//, '')} / Service: ${d.group.replace(/^.*:/, '')}`,
                    `Task: ${d.taskArn.replace(/^.*\//, '')} (${d.taskDefinitionArn.replace(/^.*\//, '')})`,
                    `Status: ${d.lastStatus} (Desired: ${d.desiredStatus})`,
                    d.stoppedReason && `Stop reason: ${d.stoppedReason}`,
                ].filter(x => x).join('\n')
                break
        }

        if (!text) return
        body = { attachments: [{ title, text, color }] }
        console.log(JSON.stringify(body)) // Debugging

        await fetch(process.env.WEBHOOK_URL, {
            method: 'post',
            body: JSON.stringify(body),
            headers: { 'Content-Type': 'application/json' },
        })
    }
};

Hi,
@statico
I'm trying to setup but I can't find file from step 7

Ah, you probably need version 2: https://unpkg.com/node-fetch@2.7.0/lib/index.js