aws-ses-to-slack

This forwards emails sent to <channel>@<your-domain> to that channel in Slack.

I recommend using a subdomain for this, e.g. slack.example.com.

Requirements

• AWS account and credentials
• Permission to add bots to the Slack workspace
• Node 16
• npm 7

First time setup

Instructions for installing in a new Slack workspace or AWS account.

Slack Bot

• Go to https://api.slack.com/apps and create a new app.
• Fill in Basic Information -> Display Information.
  Suggestions:
  • App name: EmailBot
  • Short description: Send emails to slack - <channel>@<your-domain>
  • App icon: https://pixabay.com/vectors/animal-anthropomorphized-bird-1320792/
  • Background color: #2c2d30
• Go to Bot Users and add a bot.
  Suggestions:
  • Display name: EmailBot
  • Default username: emailbot
• Go to OAuth & Permissions and add chat:write to the Bot Token Scopes.
• Open Slack and add the app.

AWS

• Open the AWS console.
• Create a new Node 16 lambda and deploy the code to it (see How to Deploy).
• SES
  • On the Identity Management -> Domains tab, add your domain and wait a few minutes for verification.
  • On the Email Receiving -> Rule Sets tab, select Create a New Rule Set then Create Rule.
    • Recipient: Your domain.
    • Action 1: S3 with a new bucket.
    • Action 2: Lambda with the lambda created earlier and for the Invocation Type select Event.
• Configure the bucket in S3
  • On the Permissions tab, block all public access.
  • On the Management tab, add a lifecycle rule to Expire current version of object after a week.
• Configure the lambda
  • Give it "s3:GetObject" permission for your S3 bucket (e.g. "arn:aws:s3:::your-bucket/*").
  • Add a S3_BUCKET environment variable with the name of your S3 bucket.
  • Add a SLACK_TOKEN environment variable with the Bot User OAuth Access Token from the Slack bot's OAuth & Permissions.
  • Add a NODE_OPTIONS environment variable with the value --enable-source-maps.

Slack channel setup

Public channels can accept emails without any extra setup. Private channels can accept emails once the EmailBot app has been added in Channel Details -> Apps.

How to deploy

• npm install
• npm run package
• Login to the AWS console and open your lambda.
• Scroll down to Function code and select Upload a .zip file.
• Upload dist/aws-ses-to-slack.zip.
• Click Save.