ECR repository/S3 Bucket of assets needs clean up

Please +1 Garbage Collection RFC

Original title: (was Lifecycle support for DockerImageAssets)

It would be helpful to apply lifecycle rules for the ECR to which DockerImageAsset’s are pushed to.

Use Case

Right now CDK automatically defines the repository and keeps all previous images stored in there. Because of rapid prototyping this causes a lot of images to build up. In order to save cost on storing these images and to declutter the interface from old unused images it would be neat to be able to define a lifecycle for these images.

Proposed Solution

Ideally it would be possible to define lifecycle rules for the DockerImageAsset itself, but exposing the Repository construct through DockerImageAsset#repository instead of the generic IRepository interface would also work:

import {DockerImageAsset} from "@aws-cdk/aws-ecr-assets";

const image = new DockerImageAsset(this, "Image", {
  directory: "path/to/dockerfile"
});

image.repository.addLifecycleRule({maxImageCount: 30})

• 👋 I may be able to implement this feature request
• ⚠️ This feature might incur a breaking change

---

This is a 🚀 Feature Request

[eladb]

The current way image assets work in the CDK implies that a single ECR repository is used for all asset images. You can use cdk-ecr-deployment in order to deploy image assets to a specific ECR repository in your control.

As for garbage collecting images from the assets ECR repository, this is something we plan to add at some point as part of a broader garbage collection capability (applies to buckets as well).

Please +1 this RFC if you want to see this prioritized: https://github.com/aws/aws-cdk-rfcs/issues/64

[DerkSchooltink]

@rix0rrr @eladb, how does this fit into the “single repository : n images” strategy? Can we add a method that lets you add lifecycle rules at the image level (by targetting specific tags based on the assets unique ID perhaps?) in addition to exposing at the repository level?

What about exposing a field on DockerImageAsset that allows for defining a repository yourself? That allows us to create an ECR separately (with the lifecycle rules) and would not mess with the single repository setup.

Example:

const repository = new Repository(this, 'Repository');
repository.addLifecycleRule({maxImageCount: 5});

const image = new DockerImageAsset(this, "Image", {
    directory: "path/to/dockerfile",
    repository: repository
});