aws-install-ssm-agent

#!/bin/bash

# This is an updated version of the aws-install-ssm-agent
# script that supports SUSE.

function die() {
    echo "$@, exiting." >&2
    exit 1
}

function get_contents() {
    if [ -x "$(which curl)" ]; then
        curl -s -f "$1"
    elif [ -x "$(which wget)" ]; then
        wget "$1" -O -
    else
        die "No download utility (curl, wget)"
    fi
}

function issue_match() {
    grep -E -i -c "$1" /etc/issue 2>&1 &>/dev/null
    [ $? -eq 0 ] && echo "true" || echo "false"
}

function is_debuntu() {
    echo "$(issue_match 'Debian|Ubuntu')"
}

function is_ubuntu() {
    echo "$(issue_match 'Ubuntu')"
}

function is_redhat() {
    if [ -f "/etc/system-release" ] ||
        [ -f "/etc/redhat-release" ]; then
        echo "true"
    else
        echo "false"
    fi
}

function is_suse() {
    if [ -f "/etc/os-release" ] ||
        [ -f "/etc/SuSE-release" ]; then
        echo "true"
    else
        echo "false"
    fi
}

function get_ubuntu_major() {
    lsb_release --release | cut -f 2 | cut -d '.' -f 1
}

function get_arch() {
    if [ "$(uname -m)" == "x86_64" ]; then
        echo "amd64"
    elif [[ "$(uname -m)" =~ i[3-6]86 ]]; then
        echo "386"
    else
        die "Unsupported architecture $(uname -m)"
    fi
}

function get_package_type() {
    if [ "$(is_debuntu)" == "true" ]; then
        echo "deb"
    elif [ "$(is_redhat|is_suse)" == "true" ]; then
        echo "rpm"
    fi
}

function get_dist() {
    if [ "$(is_debuntu)" == "true" ]; then
        echo "debian"
    elif [ "$(is_redhat|is_suse)" == "true" ]; then
        echo "linux"
    else
        die "Unknown distribution"
    fi
}

function get_ssm_agent() {
    extension="$(get_package_type)"
    dist="$(get_dist)"
    arch="$(get_arch)"

    package="amazon-ssm-agent.$extension"
    url_base="https://amazon-ssm-$REGION.s3.amazonaws.com"
    url="${url_base}/latest/${dist}_${arch}/${package}"

    get_contents "$url" > "$package"

    if [ ! -f "$package" ]; then
        die "Could not download the package from $url"
    fi
}

function start_ssm_agent() {
    if [ "$(is_ubuntu)" == "false" ]; then
        return
    fi

    case "$(get_ubuntu_major)" in
        16)
            systemctl start amazon-ssm-agent
            ;;
        14)
            start amazon-ssm-agent
            ;;
        *)
            die "Unknown major revision $(get_ubuntu_major)"
    esac
}

function install_ssm_agent() {
    if [ "$(is_debuntu)" == "true" ]; then
        dpkg -i amazon-ssm-agent.deb
    elif [ "$(is_redhat)" == "true" ]; then
        yum install --nogpgcheck -y amazon-ssm-agent.rpm
    elif [ "$(is_suse)" == "true" ]; then
        rpm --install amazon-ssm-agent.rpm
    else
        die "Unknown distribution"
    fi

    if [ ! -x "$(which amazon-ssm-agent)" ]; then
        die "No SSM agent was installed"
    fi
}

function main() {
    cd /tmp
    get_ssm_agent
    install_ssm_agent
    start_ssm_agent
}

main $@ 2>&1 | tee /tmp/aws-install-ssm-agent.log