oam/knowledge base/cloud computing/aws/ecr.md

Elastic Container Registry

1. TL;DR
2. Pull through cache feature
3. Troubleshooting
   1. Docker pull errors with no basic auth credentials
4. Further readings
   1. Sources

TL;DR

# List and get information about the repositories in ECRs.
aws ecr describe-repositories
aws ecr describe-repositories --repository-names 'docker-tools/image-builder'
aws ecr describe-repositories --registry-id '123456789012' --query 'repositories[].repositoryName'

# Create repositories.
aws ecr create-repository --repository-name 'docker-tools/image-builder'

# Delete repositories.
aws ecr delete-repository --repository-name 'banana/slug'

# List images in ECRs.
aws ecr list-images --repository-name 'repository'
aws ecr list-images --registry-id '123456789012' --repository-name 'my-image'

# Check images exist in the ECR.
[[ \
  $(
    aws ecr list-images --repository-name 'repository' \
      --query "length(imageIds[?@.imageTag=='latest'])" --output 'text' \
  ) -le 0 \
]] && echo "image 'repository:latest' exists" || echo "image 'repository:latest' does not exist"


# Use ECRs as Docker registries.
aws ecr get-login-password \
| docker login --username 'AWS' --password-stdin 'aws_account_id.dkr.ecr.region.amazonaws.com'

# Pull images from ECRs.
docker pull 'aws_account_id.dkr.ecr.region.amazonaws.com/repository_name/image_name:tag'


# List and show pull through cache rules.
aws ecr describe-pull-through-cache-rules
aws ecr describe-pull-through-cache-rules \
  --registry-id '123456789012' --ecr-repository-prefixes 'ecr-public' 'quay'

# Create pull through cache rules.
aws ecr create-pull-through-cache-rule \
  --registry-id '123456789012' --ecr-repository-prefix 'prefix' \
  --upstream-registry 'docker-hub' --upstream-registry-url 'registry-1.docker.io' \
  --credential-arn "$( \
    aws secretsmanager describe-secret --secret-id 'ecr-pullthroughcache/docker-hub' \
      --query 'ARN' --output 'text' \
  )"

# Validate pull through cache rules.
aws ecr validate-pull-through-cache-rule \
  --registry-id '123456789012' --ecr-repository-prefix 'prefix'

# Pull images from cache repositories.
docker pull 'aws_account_id.dkr.ecr.region.amazonaws.com/prefix/repository_name/image_name:tag'
docker pull '123456789012.dkr.ecr.us-east-2.amazonaws.com/ecr-public/repository_name/image_name:tag'
docker pull '123456789012.dkr.ecr.eu-west-1.amazonaws.com/quay/argoproj/argocd:v2.10.0'
# DockerHub cache repositories require the full path.
# E.g., 'library/alpine' instead of just 'alpine'.
docker pull '123456789012.dkr.ecr.eu-south-1.amazonaws.com/docker-hub/library/nginx:perl'
docker pull '123456789012.dkr.ecr.us-west-2.amazonaws.com/docker-hub/grafana/grafana'

# Check what ECR Basic Scanning technology is used by the account.
aws ecr get-account-setting --name 'BASIC_SCAN_TYPE_VERSION' --query 'value' --output 'text'
# Change it.
aws ecr put-account-setting --name 'BASIC_SCAN_TYPE_VERSION' --value 'AWS_NATIVE'
aws ecr put-account-setting --name 'BASIC_SCAN_TYPE_VERSION' --value 'CLAIR'

aws ecr describe-repositories --repository-names 'docker-tools/image-builder' \
|| aws ecr create-repository --repository-name 'docker-tools/image-builder'

Constraints:

What	Type	Constraints	Reference
Image tag	String	1 <= length <= 300	ImageIdentifier
Repository name	String	2 <= length <= 256 Must match (?:[a-z0-9]+(?:[._-][a-z0-9]+)*/)*[a-z0-9]+(?:[._-][a-z0-9]+)*	Image

Pull through cache feature

Note: when requesting an image for the first time using the pull through cache, the ECR creates a new repository for that image.
This might™ introduce a small latency and be cause of pull failures. Pulling that (not-yet)cached image from an interactive shell session worked flawlessly.

The user or role pulling the image must be granted the ecr:BatchImportUpstreamImage permission for the feature to work as expected.

Refer Troubleshooting pull through cache issues in Amazon ECR.

Troubleshooting

Docker pull errors with no basic auth credentials

Refer https://github.com/awslabs/amazon-ecr-credential-helper/issues/207.

Context: trying to pull an image on an EC2 instance that is using the amazon-ecr-credential-helper to login.

1. Check the user's ~/.ecr/log/ecr-login.log file to get detailed information.
2. Check the user's ~/.docker/config.json file has a correct PAT.
3. Check the instance's role has permissions to pull images.

Further readings

• Amazon Web Services
• AWS' CLI
• Use ECR as cache for BuildKit

Sources

• Using pull through cache rules
• Creating a lifecycle policy preview
• CLI subcommand reference