Updating managed policy in AWS

aws-update-policy-v2.sh

#!/bin/bash
set -e
#set -x

AWS_PROFILE="dev-deploy"
POLICY_ARN="arn:aws:iam::2314123:policy/PolicyName"
POLICY_DOC="file://policies/PolicyNameOnDisk.json"

which aws >/dev/null 2>&1 || ("ERROR: aws command is not installed!"; exit 1)
which jq >/dev/null 2>&1  || ("ERROR: jq command is not installed!"; exit 1)

echo "AWS_PROFILE: ${AWS_PROFILE}" > /dev/stderr
echo "POLICY_ARN : ${POLICY_ARN}" > /dev/stderr
echo "POLICY_DOC : ${POLICY_DOC}" > /dev/stderr

# At most 5 policy versions can be stored at a time. 
# Oldest needs to be deleted to be able to be able to upload a new version
function get_fifth_policy_version(){
  aws --profile "${AWS_PROFILE}" \
    iam list-policy-versions \
    --policy-arn "${POLICY_ARN}" \
  | jq -r ".Versions[4].VersionId" \
  | sed '/^null$/d'
}

old="$(get_fifth_policy_version)"
if [ -n "${old}" ];
then
    echo "Deleting oldest policy version ${old}" > /dev/stderr
    aws --profile "${AWS_PROFILE}" \
    iam delete-policy-version \
    --policy-arn "${POLICY_ARN}" \
    --version-id "$old"
fi

echo "Uploading policy..." > /dev/stderr

aws --profile "${AWS_PROFILE}" \
  iam create-policy-version \
  --policy-arn "${POLICY_ARN}" \
  --policy-document "${POLICY_DOC}" \
  --set-as-default