Script to clean up Ubuntu EC2 instance before packaging as an AMI

ami-clean.sh

#!/bin/bash

# This script cleans up your EC2 instance before baking a new AMI.
# Run the following command in a root shell:
#
# bash <(curl -s https://gist.github.com/justindowning/5921369/raw/ami-clean.sh)

function print_green {
  echo -e "\e[32m${1}\e[0m"
}

print_green 'Clean Apt'
apt-get -y autoremove
aptitude clean
aptitude autoclean

print_green 'Remove SSH keys'
[ -f /home/ubuntu/.ssh/authorized_keys ] && rm /home/ubuntu/.ssh/authorized_keys
 
print_green 'Cleanup log files'
find /var/log -type f | while read f; do echo -ne '' > $f; done

print_green 'Cleanup bash history'
unset HISTFILE
[ -f /root/.bash_history ] && rm /root/.bash_history
[ -f /home/ubuntu/.bash_history ] && rm /home/ubuntu/.bash_history

print_green 'AMI cleanup complete!'

Also maybe delete generated rsa keys (Debian)

shred -u /etc/ssh/*_key /etc/ssh/*_key.pub

Any suggestion how can we execute this script automatically on Ec2 instance once the provisioning is done? Also, is it okay to clean the cloud-init cache from within the user-data script?