"script" to clean up Ecs services created for closed PR's

ecs_pr_cleanup.sh

#!/usr/bin/env bash
# retrieve list of closed github PRs, compare to running Ecs services, stop and delete services and deregister task-definitions

# settings
github_token='YOURGITHUBTOKEN' # github token with access to organization pull-requests
github_repo='SOMEORG/SOMEREPO' # org/repo from which to retrieve pullrequest status
cluster_arn='SOME_ECS_CLUSTER' # full arn or shortname of Ecs cluster

# retrieve list of closed pull-requests
closed_pulls="^($(curl -s -G -d access_token="$github_token" https://api.github.com/repos/"$github_repo"/pulls?state=closed | jq .[].number | sort -n | paste -sd'|' -))$"

# match PR number in service-arns with id number of closed pull-requests (service name is of form "some-app-pr123")
# TODO: when more projects/repos will use this system, PR numbers might overlap, need fix
closed_services=$(for i in $(aws ecs list-services --cluster "$cluster_arn" --output text | awk '{print $2}'); do prnum=$(echo "$i" | egrep -o 'pr\d{1,3}' | sed 's/pr//'); if [[ "$prnum" =~ $closed_pulls ]]; then echo "$i"; fi; done)

# retrieve list of task-arns in use by services to be removed
closed_tasks=$(for service in $closed_services; do aws ecs describe-services --cluster "$cluster_arn" --services "$service" --query 'services[].taskDefinition' --output text; done)

# make service ready for delete
for i in $closed_services; do echo $i; aws ecs update-service --cluster "$cluster_arn" --service $i --desired-count 0; done
# delete service
for i in $closed_services; do echo $i; aws ecs delete-service --cluster "$cluster_arn" --service $i; done
# delete associated tasks (just the revision latest in use)
# TODO: delete all revisions
for i in $closed_tasks; do echo $i; aws ecs deregister-task-definition --task-definition $i; done