Find the AMI details for a deployed managed nodegroup on AWS

find-nodegroup-ami.sh

#!/usr/bin/env bash
: "${nodegroup:?Need nodegroup}"
: "${region:?Need region}"
: "${cluster:?Need cluster}"

# Get the autoscaling group name from the EKS node pool
autoscaling_group_name=$(aws --region "${region}" eks describe-nodegroup --cluster-name "${cluster}" --nodegroup-name "${nodegroup}" --output json | jq '.nodegroup.resources.autoScalingGroups | last | .name' -r)
# Determine the ASG launch template for this ASG
launch_template_name=$(aws --region "${region}" autoscaling describe-auto-scaling-groups --auto-scaling-group-names "${autoscaling_group_name}" | jq '.AutoScalingGroups | last | .MixedInstancesPolicy.LaunchTemplate.LaunchTemplateSpecification.LaunchTemplateName' -r )
# Now query the image ID for that template
ami_id=$(aws --region "${region}" ec2 describe-launch-template-versions --launch-template-name "${launch_template_name}" --output json | jq '.LaunchTemplateVersions | last' | jq '.LaunchTemplateData.ImageId' -r)
# Pull out the AMI version
ami_name=$(aws --region "${region}" ec2 describe-images --image-ids "${ami_id}" | jq '.Images | last | .Name' -r)
# Get the AMI tag
ami_version=$(printf "${ami_name}" | grep -E "[^-]+$" -o)
# Get the URL encoded link that finds that text
ami_fragment=$(printf "${ami_name}" | jq -sRr @uri)
# Display the URL to the release
echo "https://github.com/awslabs/amazon-eks-ami/releases/tag/${ami_version}#:~:text=${ami_fragment}"