How do I create Docker image assets in CDK from a docker-compose file?

Question

I'm using CDK to deploy an application that uses containers defined in a docker-compose file. I can see that there are ways to create image assets from Dockerfiles, such as the DockerImageAsset class or the ContainerImage.fromAsset method. But I can't find any resources for working with services defined in a docker-compose.yml file. I could build the images locally and push to ECR, but it would be nice to have this process automated. What is the best way to handle this?

Answer 1

I have not used or seen docker-compose used with CDK, but CDK would be for defining the infrastructure on AWS and docker-compose for running the stack locally I imagine, not using compose with CDK.

You reference a Dockerfile in your CDK setup and CDK builds it for you and pushes it to ECR. The ECR repo is set up by CDK when running ``. So that handles that part for you behind the scenes. Quite convenient!

When you define CDK code that references a Dockerfile, you then pass the referenced image of the created ECR image to a task definition, for example, that then uses the image in AWS when deployed. Same can be done using lambdas also.

I hope this example below clears it up a bit. You could then for example use a pipeline like github actions or circleci to create a job that runs CDK deploy for you.

// This pushes it to ECR after building the file
const dockerImage = new DockerImageAsset(this, 'some-image', {
  directory: path.join(__dirname, '../../')
})

this.loadBalancer = new ApplicationLoadBalancedFargateService(this, `${namePrefix}-lb`, {
  cluster,
  serviceName: `${namePrefix}-lb`,
  taskImageOptions: {
    containerName: `${namePrefix}-task`,
    image: ecs.ContainerImage.fromDockerImageAsset(dockerImage), <-- this is where you pass the docker image reference
    environment: containerEnvs,
    containerPort: parseInt(containerEnvs.PORT),
    enableLogging: true,
    taskRole: role,
  },
})