Send AWS CloudWatch notifications to a Slack channel using Lambda
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proAlexandr and creichert Improved configuration of the tool (#30)
* Customization improvements

    1) Fill variables in .env instead deploy.env and Makefile
    2) Autodetecting CloudWatch events.
    3) Remove slackbot customization

* Use npm scripts instead of makefile
* Fix image urls in readme
* Changed env variables examples and fixed names in scripts
* Remove old node versions from TravisCI
Latest commit aac6157 Oct 13, 2018


An AWS Lambda function for better Slack notifications. Check out the blog post.

BuildStatus NPM version


This function was originally derived from the AWS blueprint named cloudwatch-alarm-to-slack. The function in this repo improves on the default blueprint in several ways:

Better default formatting for CloudWatch notifications:

AWS Cloud Notification for Slack

Support for notifications from Elastic Beanstalk:

Elastic Beanstalk Slack Notifications

Support for notifications from Code Deploy:

AWS CodeDeploy Notifications

Basic support for notifications from ElastiCache:

AWS ElastiCache Notifications

Support for encrypted and unencrypted Slack webhook url:


1. Clone this repository

2. Configure environment variables

cp .env.example .env

Fill in the variables in the .env.

3. Setup Slack hook

Follow these steps to configure the webhook in Slack:

  1. Navigate to and search for and select "Incoming WebHooks".

  2. Choose the default channel where messages will be sent and click "Add Incoming WebHooks Integration".

  3. Copy the webhook URL from the setup instructions and use it in the next section.

  4. Click 'Save Settings' at the bottom of the Slack integration page.

Encrypted the Slack webhook URL

If you don't want or need to encrypt your hook URL, you can use the UNENCRYPTED_HOOK_URL. If this variable is specified, the KMS_ENCRYPTED_HOOK_URL is ignored.

If you do want to encrypt your hook URL, follow these steps to encrypt your Slack hook URL for use in this function:

  1. Create a KMS key -

  2. Encrypt the event collector token using the AWS CLI. $ aws kms encrypt --key-id alias/ --plaintext "<SLACK_HOOK_URL>"

    Note: You must exclude the protocol from the URL (e.g. "").

  3. Copy the base-64 encoded, encrypted key (CiphertextBlob) to the ENCRYPTED_HOOK_URL variable.

  4. Give your function's role permission for the kms:Decrypt action. Example:

    "Version": "2012-10-17",
    "Statement": [
            "Sid": "Stmt1443036478000",
            "Effect": "Allow",
            "Action": [
            "Resource": [
                "<your KMS key ARN>"

4. Deploy to AWS Lambda

The final step is to deploy the integration to AWS Lambda:

npm install
npm run deploy


With the variables filled in, you can test the function:

npm install
npm test


MIT License