Send CloudWatch Alarms to Slack with AWS Lambda

Read the full blog post on cloudonaut.io.

Or use marbot, a free chatbot ensuring you never miss an alert from Amazon Web Services including CloudWatch.

Slack setup

1. Start by setting up an incoming webhook integration in your Slack workspace: https://my.slack.com/services/new/incoming-webhook/
2. Select a channel or create a new one
3. Click on Add Incoming WebHooks integration
4. You are redirected to a new page where you can see your Webhook URL. Copy the value; you will need it soon.

AWS setup

1. Clone or download this respository
2. create a S3 bucket for SAM (replace $UniqueSuffix with e.g. your username): aws --region us-east-1 s3 mb s3://cw-to-slack-$UniqueSuffix
3. Install Node.js dependencies: npm install
4. package the Lambda function code (replace $UniqueSuffix with e.g. your username): aws --region us-east-1 cloudformation package --s3-bucket cw-to-slack-$UniqueSuffix --template-file template.yml --output-template-file template.sam.yml
5. Deploy the CloudFormation stack (replace $WebhookURL with your URL from Slack): aws --region us-east-1 cloudformation deploy --parameter-overrides "WebhookURL=$WebhookURL" --template-file template.sam.yml --stack-name cw-to-slack --capabilities CAPABILITY_IAM