Create own AMI from instance

Tested on AWS Ubuntu Xenial create-own-ami.sh:

#!/bin/bash

set -e

instance_id=$(ec2metadata --instance-id)
instance_name=$(aws ec2 describe-tags --filters Name=resource-id,Values=$instance_id Name=key,Values=Name --query Tags[].Value --output text)

if [ -z $instance_name ]; then
        ami_name="ec2-$instance_id-auto-created"
else
        ami_name="$instance_name-auto-created"
fi

ami_description="AMI auto created by script from instance $instance_id"

function delete_snapshots_of_ami() {
        array=($(aws ec2 describe-images --filters "Name=image-id,Values=$1" --query Images[0].BlockDeviceMappings[].Ebs.SnapshotId --output text))

        for i in "${array[@]}"
        do
                aws ec2 delete-snapshot --snapshot-id $i
                echo 'Deleted snapshot $i'
        done

}


function delete_ami() {
        ami_id=$1

        snapshots=($(aws ec2 describe-images --filters "Name=image-id,Values=$ami_id" --query Images[0].BlockDeviceMappings[].Ebs.SnapshotId --output text))

        aws ec2 deregister-image --image-id $ami_id
        echo "Deregistered AMI $ami_id"

        sleep 5.0

        for snap_id in "${snapshots[@]}"
        do
                aws ec2 delete-snapshot --snapshot-id $snap_id
                echo "Deleted snapshot $snap_id"
        done
}


ami_last_id=$(aws ec2 describe-images --filters "Name=name,Values=$ami_name" --query Images[0].ImageId --output text)

if [ "$ami_last_id" = "None" ]; then
        echo "Not exist previous AMI. Nothing to delete."
else
        echo "Start deleting previous AMI $ami_name with id $ami_last_id"
        delete_ami $ami_last_id

        echo "Previous AMI and associated snapshots were deleted."
fi

echo "Start creating AMI $ami_name from $instance_id"
ami_new_id=$(aws ec2 create-image --instance-id $instance_id --name "$ami_name" --description "$ami_description" --output text)

echo "Created new AMI $ami_new_id"