@richicoder/cdk-ecs-s3volume

An ECS Task Extension that mounts a volume to ECS container(s) and either copies a local file or files from a bucket into that volume.

Useful as a replacement for ConfigMap in EKS since there is (currently) no native ECS equivalent.

Usage

Install:

npm i @richicoder/cdk-ecs-s3volume

Adding a file

taskDefinition.addExtension(S3Volume.fromAsset('stacks/config-prod.yml', '/etc/config/config-prod.yaml'/*, options */));

This will result in stacks/config-prod.yml being available read-only in the container at /etc/config/config-prod.yaml.

Important: fromAsset only supports a single file. To copy multiple files, use your own bucket with s3-deployment and the steps below.

Adding a bucket's contents

const bucket: Bucket
taskDefinition.addExtension(S3Volume.fromBucket(bucket/*, options */));
/* or */
taskDefinition.addExtension(new S3Volume('ConfigVolume', {
  bucket: 'my-config-bucket',
}));

Assuming a bucket with name my-config-bucket and objects config.yml and config-prod.yml, this will result in a readOnly volume at /etc/s3/my-config-bucket/ containing the files config.yml and config-prod.yml.

Results in a readOnly volume at /etc/config/ with file config-prod.yml.

Overriding container path

The path in the container defaults to /etc/s3/${bucketName}/* but can be overidden by passing containerPath to options.

taskDefinition.addExtension(new S3Volume('ConfigVolume', {
  bucket: 'my-data-bucket',
  containerPath: `/data/my-data/`
}));

Copying multiple local files

Sometimes you might want to copy multiple files from local source into a container. To do this, you can combine bucket volumes with CDK's Bucket Deployment construct.

const configBucket = new s3.Bucket(this, 'ConfigBucket');

new s3deploy.BucketDeployment(this, 'Configs', {
  sources: [s3deploy.Source.asset('./configs')],
  destinationBucket: configBucket,
});

taskDefinition.addExtension(S3Volume.fromBucket(configBucket));

or when using a shared bucket, you might want to use a specific key path:

const configBucket: Bucket;

new s3deploy.BucketDeployment(this, 'Configs', {
  sources: [s3deploy.Source.asset('./configs')],
  destinationBucket: configBucket,
  destinationKeyPrefix: 'my/service',
});

taskDefinition.addExtension(S3Volume.fromBucket(configBucket, {
  // See https://docs.aws.amazon.com/cli/latest/reference/s3/index.html#use-of-exclude-and-include-filters for more details
  extraOptions: [`--exclude="*"`, `--include="my/service/*"`]
}));

API

API