cfn-cloudwatch-events-target

Purpose

AWS CloudFormation does not support AWS CloudWatch Events Targets. This is a Lambda-backed custom resource to add support for AWS CloudWatch Events Targets to CloudFormation.

This package on NPM
This package on GitHub

Implementation

This Lambda makes use of the Lambda-Backed CloudFormation Custom Resource flow module, cfn-lambda (GitHub / NPM).

Usage

See ./example.template.json for a sample CloudFormation template. The example uses Condition statements, Parameters, and dynamic ServiceToken generation fully.

The example template also depends on another Custom Resource, cfn-cloudwatch-events-rule. Make sure to install it via npm run cfn-lambda-deploy as described below before trying to use this example template.

"ResourceLogicalIdInResourcesObject": {
  "Type": "Type": "Custom::CloudWatchEventsTarget",
  "Properties": {
    "ServiceToken": "arn:aws:lambda:<cfn-region-id>:<your-account-id>:function:<this-deployed-lambda-name>",

    "Input": "{\"foo\": \"bar\"}", /* Static JSON to pass to TargetArn
                                  Will override InputPath */
    "InputPath": "$.json.path", /* JSONPath expression to extract from event
                                Omitting both this and Input
                                defaults to "$" (whole object) */
    "RuleArn": "SOME_ARN", /* required, update requires replacement */
    "TargetArn": "SOME_ARN" /* required */
  }
}

Installation of the Resource Service Lambda

Using the Provided Instant Install Script

The way that takes 10 seconds...

# Have aws CLI installed + permissions for IAM and Lamdba
$ npm run cfn-lambda-deploy

You will have this resource installed in every supported Region globally!

Using the AWS Console

... And the way more difficult way.

IMPORTANT: With this method, you must install this custom service Lambda in each AWS Region in which you want CloudFormation to be able to access the CloudWatchEventsTarget custom resource!

1. Go to the AWS Lambda Console Create Function view:

• us-east-1 / N. Virginia
• us-west-2 / Oregon
• eu-west-1 / Ireland
• ap-northeast-1 / Tokyo

2. Zip this repository into /tmp/CloudWatchEventsTarget.zip

   $ cd $REPO_ROOT && zip -r /tmp/CloudWatchEventsTarget.zip;

3. Enter a name in the Name blank. I suggest: CfnLambdaResouce-CloudWatchEventsTarget

4. Enter a Description (optional).

5. Toggle Code Entry Type to "Upload a .ZIP file"

6. Click "Upload", navigate to and select /tmp/CloudWatchEventsTarget.zip

7. Set the Timeout under Advanced Settings to 10 sec

8. Click the Role dropdown then click "Basic Execution Role". This will pop out a new window.

9. Select IAM Role, then select option "Create a new IAM Role"

10. Name the role lambda_cfn_elasticsearch_domain (or something descriptive)

11. Click "View Policy Document", click "Edit" on the right, then hit "OK"

12. Copy and paste the ./execution-policy.json document.

13. Hit "Allow". The window will close. Go back to the first window if you are not already there.

14. Click "Create Function". Finally, done! Now go to Usage or see the example template. Next time, stick to the instant deploy script.

Miscellaneous

Collaboration & Requests

Submit pull requests or Tweet @ayetempleton if you want to get involved with roadmap as well, or if you want to do this for a living :)

License

MIT

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Work is (extremely) active, published here:
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