Ubuntu Auto-Update Script

autoupdate.sh

#!/bin/bash

# to install directly from the Gist
# curl https://gist.githubusercontent.com/realslacker/6dce254e16003fbec5451689c9ba1e49/raw/ | bash -s -- -i

# test getopt
getopt --test > /dev/null
if [[ $? -ne 4 ]]; then
    echo "Error: `getopt --test` failed in this environment, please update to a newer 'getopt' package"
    exit 1
fi

# test realpath
command -v realpath >/dev/null 2>&1 || {
    echo >&2 "I require realpath but it's not installed."
    exit 1
}

OPTIONS=iurhn
LONGOPTIONS=install,update,remove,help,norestart

auto_restart=true

function _help() {

    echo "this is the help"
    # screen -d -m -t updates ./do_updates.sh

    exit 0

}

function _install() {

    # download and install
    wget --output-document="autoupdate.sh" https://gist.githubusercontent.com/realslacker/6dce254e16003fbec5451689c9ba1e49/raw/
    chmod +x "autoupdate.sh"
    
    # make log dir
    if [ ! -d /var/log/autoupdate ]; then
        mkdir -p /var/log/autoupdate
    fi

    # create the logrotate file
    if [ ! -f /etc/logrotate.d/autoupdate ]; then
        cat > /etc/logrotate.d/autoupdate <<LOGROTATE
/var/log/autoupdate/lastrun.log {
    rotate 14
    daily
    missingok
}
LOGROTATE
    fi
    
    if [ "$0" == "bash" ]; then
        script=`realpath autoupdate.sh`
    else
        script=`realpath $0`
    fi
    
    # add script to crontab
    crontab -l | grep -v "$script" | crontab -
    crontab -l | { cat; echo "0 3 * * 0 $script"; } | crontab -

    echo "Installation Finished"

}

function _update() {

    script=`realpath $0`

    wget --output-document="$script.tmp" https://gist.githubusercontent.com/realslacker/6dce254e16003fbec5451689c9ba1e49/raw/
    chmod +x "$script.tmp"
    mv "$script.tmp" "$script"

    echo "Upgrade Finished"

}

function _remove() {

    script=`realpath $0`

    if [ -f /etc/logrotate.d/autoupdate ]; then
        rm /etc/logrotate.d/autoupdate
    fi

    if [ -d /var/log/autoupdate ]; then
        rm -rf /var/log/autoupdate
    fi

    crontab -l | grep -v "$script" | crontab -

    echo "Remove Finished"

}

# -temporarily store output to be able to check for errors
# -e.g. use <93>--options<94> parameter by name to activate quoting/enhanced mode
# -pass arguments only via   -- "$@"   to separate them correctly
PARSED=$(getopt --options=$OPTIONS --longoptions=$LONGOPTIONS --name "$0" -- "$@")
if [[ $? -ne 0 ]]; then
    # e.g. $? == 1
    #  then getopt has complained about wrong arguments to stdout
    exit 2
fi
# read getopt<92>s output this way to handle the quoting right:
eval set -- "$PARSED"

# now enjoy the options in order and nicely split until we see --
while true; do
    case "$1" in
        -i|--install)
            _install
            exit 0
            ;;
        -u|--update)
            _update
            exit 0
            ;;
        -r|--remove)
            _remove
            exit 0
            ;;
        -h|--help)
            _help
            exit 0
            ;;
        -n|--norestart)
            auto_restart=false
            shift
            break
            ;;
        --)
            shift
            break
            ;;
        *)
            echo "Programming error"
            exit 3
            ;;
    esac
done

echo "Running..."

# check for log director, if it doesn't exist turn off logging
if [ ! -d /var/log/autoupdate ]; then
    logfile=/dev/null
else
    logfile=/var/log/autoupdate/lastrun.log
fi

echo "Automatic Update Script Run" > $logfile
date >> $logfile

DEBIAN_FRONTEND=noninteractive

apt-get update --yes | tee --append $logfile
apt-get upgrade -o Dpkg::Options::="--force-confnew" --yes | tee --append $logfile
apt-get dist-upgrade -o Dpkg::Options::="--force-confnew" --yes | tee --append $logfile
apt-mark auto ^linux-image- | tee --append $logfile
apt-get autoremove --yes | tee --append $logfile

if [ $logfile != '/dev/null' ]; then

    if [ $( grep -Po '\d+(?= (upgraded|newly installed|to remove))' /var/log/autoupdate/lastrun.log | awk '{ SUM += $1 } END { print SUM }' ) -gt 0 ]; then

        if [ $auto_restart = false ]; then
    
            echo "Skipping required reboot, please restart this server"
            
        else
            
            echo "Rebooting server..."
            reboot
            
        fi

    else

        echo "No reboot required."

    fi

fi