showaltb / cfn-empty-ecr-repository

AWS CloudFormation Custom Resource Lambda to empty an ECR Repository

cfn-empty-ecr-repository

AWS CloudFormation Custom Resource Lambda to empty an ECR Repository

This project defines a NodeJS Lambda function to back a CloudFormation custom resource that will delete images from an ECR repository. This allows you to automatically delete a repository when you delete a stack, as only empty repositories can be deleted.

Installing

Prerequisites:

• AWS CLI
• Yarn 1.22 or higher (or npm)
• NodeJS 12.x or higher (for adding dummy images to repository)
• Docker (for adding dummy images to repository)

Clone the repository:

git clone [e-mail]:showaltb/cfn-empty-ecr-repository.git
cd cfn-empty-ecr-repository

Now copy .env.example to .env and set the following variables:

• AWS_PROFILE - AWS CLI profile name
• AWS_REGION - AWS region to create the stack in
• STACK_NAME - CloudFormation stack to create

Then create the stack:

yarn deploy

The included stack (template.yml) will create the following resources:

• Repository - An ECR repository for testing purposes
• EmptyEcrRepositoryRole - Lambda execution role giving the function permission to list and remove images from the repository.
• EmptyEcrRepository - Lambda function for the custom resource to empty the repository on delete.
• RepositoryEmptier - A custom resource that uses the Lambda function to empty the repository on delete.

Adding Dummy Images to the Repository

You can add dummy images to the repository to test that the repository is emptied properly when the stack is deleted:

yarn fill-repository

This will use Docker to build three small hello-world images and push them to the repository. Each image will have a random tag. To push more images, repeat the command.

Deleting the Stack

To delete the stack, which will invoke the custom resource to delete any images in the ECR repository before deleting it:

yarn delete-stack