assume-role.sh

#!/bin/sh

AWS_PROFILE=${AWS_PROFILE:="default"}
AWS_ROLE_SESSION_NAME=$(date +%Y%m%d%H%M%S-session)
DURATION="7200"

print_help() {
  cat <<-EOF >> /dev/stdout
        Get and Set AWS_SESSION_TOKEN Environment

        Depends:
                 jq (https://stedolan.github.io/jq/)

        Usage: $0 [-p AWS_PROFILE] [-d DURATION]

        Options:
                 -p [AWS_PROFILE]               AWS Profile
                 -d [DURATION]                  The duration, in seconds, of the role session
                 -h                             print this message and exit

        Example: source $0 -p test-account && env | grep AWS
EOF
}

while getopts "p:d:h" opt; do
  case ${opt} in
      p ) AWS_PROFILE=${OPTARG} ;;
      d ) DURATION=${OPTARG} ;;
      h ) print_help; exit ;;
      * ) print_help; exit 1 ;;
  esac
done

shift  $((OPTIND - 1))

ROLE_ARN=$(aws --profile ${AWS_PROFILE} configure get role_arn)
TEMP_ROLE=$(aws --profile ${AWS_PROFILE} sts assume-role --role-arn ${ROLE_ARN} --role-session-name ${AWS_ROLE_SESSION_NAME} --duration-seconds ${DURATION})
export AWS_ACCESS_KEY_ID=$(echo ${TEMP_ROLE} | jq -r '.Credentials.AccessKeyId')
export AWS_SECRET_ACCESS_KEY=$(echo ${TEMP_ROLE} | jq -r '.Credentials.SecretAccessKey')
export AWS_SESSION_TOKEN=$(echo ${TEMP_ROLE} | jq -r '.Credentials.SessionToken')