Locate AWS EC2 instances that have been stopped for more than a defined number of days

aws-ec2-stale-instances

#!/bin/bash

# Locate stale AWS EC2 Instances

# This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.


function show_help() {
  echo "$0: -s <running|stopped> -p <aws-cli-profile> -a <max-age> -r <aws-region> -v"
}

OPTIND=1 # Reset in case getopts has been used previously in the shell.

# Initialize our own variables:
OWNER=""
VERBOSE=0
PROFILE="default"
REGION="us-east-1"
MAX_AGE=30
MAX_DATE=$(date --date "today -${MAX_AGE} day" +%Y-%m-%d)

while getopts "h?vo:r:p:s:a:" opt; do
    case "$opt" in
    h|\?)
        show_help
        exit 0
        ;;
    v)  VERBOSE=1
        ;;
    o)  OWNER="--owner-ids ${OPTARG}"
        ;;
    s)  STATE=$OPTARG
        ;;
    r)  REGION=$OPTARG
        ;;
    p)  PROFILE=$OPTARG
        ;;
    a)  MAX_AGE=$OPTARG
        MAX_DATE=$(date --date "today -${MAX_AGE} day" +%Y-%m-%d)
        ;;
    esac
done

shift $((OPTIND-1))

[ "${1:-}" = "--" ] && shift

INSTANCES="/tmp/instances.txt"

aws --profile ${PROFILE} --region ${REGION} ec2 describe-instances \
    --filters Name=instance-state-name,Values=${STATE} --output text \
    --query 'Reservations[*].Instances[*].InstanceId' > ${INSTANCES}

if [[ ${VERBOSE} == 1 ]]
then
  INSTANCECOUNT=$(grep -o 'i\-' ${INSTANCES} | wc -l)
  echo "Scanning ${INSTANCECOUNT} instances"
fi

for instance in $(cat ${INSTANCES})
do
  if [[ ${VERBOSE} == 1 ]]
  then
    echo "Checking: $instance"
  fi

  STR=$(aws --profile ${PROFILE} --region ${REGION} ec2 describe-instances --instance-ids ${instance} --output text --query 'Reservations[*].Instances[*].StateTransitionReason')

  # Not all stopped instances contain the time they were stopped
  if [[ "${STR}" =~ .*"GMT".* ]]
  then
    TEMP="$(echo ${STR} | sed 's/User initiated //' | tr -d '\(' | tr -d '\)')"
    STOPPED_DATE=$(date --date "${TEMP}" +%Y-%m-%d)
    if [[ ${STOPPED_DATE} < ${MAX_DATE} ]]
    then
       echo "Instance: ${instance} has been stopped for more than ${MAX_AGE} days"
    fi
  fi

done

rm -f ${INSTANCES}

exit 0