install.sh

#!/usr/bin/env bash

: ${GEM:=}
gems=${GEM//,/ }

USERNAME=${USERNAME:-${_REMOTE_USER:-"automatic"}}

set -e

export TMPDIR=$(mktemp -d /tmp/feature.XXXXXX)
trap "rm -rf $TMPDIR" EXIT

# Clean up
rm -rf /var/lib/apt/lists/*

if [ "$(id -u)" -ne 0 ]; then
    echo -e 'Script must be run as root. Use sudo, su, or add "USER root" to your Dockerfile before running this script.'
    exit 1
fi

architecture="$(dpkg --print-architecture)"
if [ "${architecture}" != "amd64" ] && [ "${architecture}" != "arm64" ]; then
    echo "(!) Architecture $architecture unsupported"
    exit 1
fi

# Determine the appropriate non-root user
if [ "${USERNAME}" = "auto" ] || [ "${USERNAME}" = "automatic" ]; then
    USERNAME=""
    POSSIBLE_USERS=("vscode" "node" "codespace" "$(awk -v val=1000 -F ":" '$3==val{print $1}' /etc/passwd)")
    for CURRENT_USER in "${POSSIBLE_USERS[@]}"; do
        if id -u "${CURRENT_USER}" >/dev/null 2>&1; then
            USERNAME=${CURRENT_USER}
            break
        fi
    done
    if [ "${USERNAME}" = "" ]; then
        USERNAME=root
    fi
elif [ "${USERNAME}" = "none" ] || ! id -u ${USERNAME} >/dev/null 2>&1; then
    USERNAME=root
fi

apt_get_update() {
    if [ "$(find /var/lib/apt/lists/* | wc -l)" = "0" ]; then
        echo "Running apt-get update..."
        apt-get update -y
    fi
}

# Checks if packages are installed and installs them if not
check_packages() {
    if ! dpkg -s "$@" >/dev/null 2>&1; then
        apt_get_update
        apt-get -y install --no-install-recommends "$@"
    fi
}

export DEBIAN_FRONTEND=noninteractive

### BEGIN install

if [ -z "${gems}" ]; then
    echo "No RubyGems specified. Skip installation..."
    exit 0
fi

check_packages ruby-full ca-certificates
echo "Installing gems..."

args=("$gems")
[ -n "${VERSION:-}" ] && args+=(--version "${VERSION}")
[ -n "${PRERELEASE:-}" ] && args+=(--prerelease)

gem install "${args[@]}"

echo "Done!"

### END install

# Clean up
rm -rf /var/lib/apt/lists/*

echo "Done!"