Package software.amazon.awscdk.services.ecr.assets

package software.amazon.awscdk.services.ecr.assets

AWS CDK Docker Image Assets

This module allows bundling Docker images as assets.

Images from Dockerfile

Images are built from a local Docker context directory (with a Dockerfile), uploaded to Amazon Elastic Container Registry (ECR) by the CDK toolkit and/or your app's CI/CD pipeline, and can be naturally referenced in your CDK app. 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .build();

The directory my-image must include a Dockerfile.

This will instruct the toolkit to build a Docker image from my-image, push it to an Amazon ECR repository and wire the name of the repository as CloudFormation parameters to your stack.

By default, all files in the given directory will be copied into the docker build context. If there is a large directory that you know you definitely don't need in the build context you can improve the performance by adding the names of files and directories to ignore to a file called .dockerignore, or pass them via the exclude property. If both are available, the patterns found in exclude are appended to the patterns found in .dockerignore.

The ignoreMode property controls how the set of ignore patterns is interpreted. The recommended setting for Docker image assets is IgnoreMode.DOCKER. If the context flag @aws-cdk/aws-ecr-assets:dockerIgnoreSupport is set to true in your cdk.json (this is by default for new projects, but must be set manually for old projects) then IgnoreMode.DOCKER is the default and you don't need to configure it on the asset itself.

Use asset.imageUri to reference the image. It includes both the ECR image URL and tag.

Use asset.imageTag to reference only the image tag.

You can optionally pass build args to the docker build command by specifying the buildArgs property. It is recommended to skip hashing of buildArgs for values that can change between different machines to maintain a consistent asset hash.

Additionally, you can supply buildSecrets. Your system must have Buildkit enabled, see https://docs.docker.com/build/buildkit/.

SSH agent sockets or keys may be passed to docker build via buildSsh. 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .buildArgs(Map.of(
                 "HTTP_PROXY", "http://10.20.30.2:1234"))
         .invalidation(DockerImageAssetInvalidationOptions.builder()
                 .buildArgs(false)
                 .build())
         .build();

You can optionally pass a target to the docker build command by specifying the target property: 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .target("a-target")
         .build();

You can optionally pass networking mode to the docker build command by specifying the networkMode property: 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 import software.amazon.awscdk.services.ecr.assets.NetworkMode;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .networkMode(NetworkMode.HOST)
         .build();

You can optionally pass an alternate platform to the docker build command by specifying the platform property: 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 import software.amazon.awscdk.services.ecr.assets.Platform;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .platform(Platform.LINUX_ARM64)
         .build();

You can optionally pass an array of outputs to the docker build command by specifying the outputs property: 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 import software.amazon.awscdk.services.ecr.assets.Platform;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .outputs(List.of("type=local,dest=out"))
         .build();

You can optionally pass cache from and cache to options to cache images: 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 import software.amazon.awscdk.services.ecr.assets.Platform;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .cacheFrom(List.of(DockerCacheOption.builder().type("registry").params(Map.of("ref", "ghcr.io/myorg/myimage:cache")).build()))
         .cacheTo(DockerCacheOption.builder().type("registry").params(Map.of("ref", "ghcr.io/myorg/myimage:cache", "mode", "max", "compression", "zstd")).build())
         .build();

You can optionally disable the cache: 

 import software.amazon.awscdk.services.ecr.assets.DockerImageAsset;
 import software.amazon.awscdk.services.ecr.assets.Platform;
 
 
 DockerImageAsset asset = DockerImageAsset.Builder.create(this, "MyBuildImage")
         .directory(join(__dirname, "my-image"))
         .cacheDisabled(true)
         .build();

Images from Tarball

Images are loaded from a local tarball, uploaded to ECR by the CDK toolkit and/or your app's CI-CD pipeline, and can be naturally referenced in your CDK app. 

 import software.amazon.awscdk.services.ecr.assets.TarballImageAsset;
 
 
 TarballImageAsset asset = TarballImageAsset.Builder.create(this, "MyBuildImage")
         .tarballFile("local-image.tar")
         .build();

This will instruct the toolkit to add the tarball as a file asset. During deployment it will load the container image from local-image.tar, push it to an Amazon ECR repository and wire the name of the repository as CloudFormation parameters to your stack.

Publishing images to ECR repositories

DockerImageAsset is designed for seamless build & consumption of image assets by CDK code deployed to multiple environments through the CDK CLI or through CI/CD workflows. To that end, the ECR repository behind this construct is controlled by the AWS CDK. The mechanics of where these images are published and how are intentionally kept as an implementation detail, and the construct does not support customizations such as specifying the ECR repository name or tags.

We are testing a new experimental synthesizer, the App Staging Synthesizer that creates separate support stacks for each CDK application. Unlike the default stack synthesizer, the App Staging Synthesizer creates unique ECR repositories for each DockerImageAsset, allowing lifecycle policies to only retain the last n images. This is a great way to keep your ECR repositories clean and reduce cost. You can learn more about this feature in this blog post.

Alternatively, If you are looking for a way to publish image assets to an ECR repository in your control, you should consider using cdklabs/cdk-ecr-deployment, which is able to replicate an image asset from the CDK-controlled ECR repository to a repository of your choice.

Here an example from the cdklabs/cdk-ecr-deployment project: 

 // This example available in TypeScript only
 
 import { DockerImageAsset } from 'aws-cdk-lib/aws-ecr-assets';
 import * as ecrdeploy from 'cdk-ecr-deployment';
 
 const image = new DockerImageAsset(this, 'CDKDockerImage', {
   directory: path.join(__dirname, 'docker'),
 });
 
 new ecrdeploy.ECRDeployment(this, 'DeployDockerImage', {
   src: new ecrdeploy.DockerImageName(image.imageUri),
   dest: new ecrdeploy.DockerImageName(`${cdk.Aws.ACCOUNT_ID}.dkr.ecr.us-west-2.amazonaws.com/test:nginx`),
 });

⚠️ Please note that this is a 3rd-party construct library and is not officially supported by AWS. You are welcome to +1 this GitHub issue if you would like to see native support for this use-case in the AWS CDK.

Pull Permissions

Depending on the consumer of your image asset, you will need to make sure the principal has permissions to pull the image.

In most cases, you should use the asset.repository.grantPull(principal) method. This will modify the IAM policy of the principal to allow it to pull images from this repository.

If the pulling principal is not in the same account or is an AWS service that doesn't assume a role in your account (e.g. AWS CodeBuild), you must either copy the image to a new repository, or grant pull permissions on the resource policy of the repository. Since the repository is managed by the CDK bootstrap stack, the following permissions must be granted there, or granted manually on the repository: "ecr:GetDownloadUrlForLayer", "ecr:BatchGetImage" and "ecr:BatchCheckLayerAvailability".