install.sh

#!/usr/bin/env bash
set -euo pipefail
export DEBIAN_FRONTEND=noninteractive

# ===== CONFIG =====
# Username to be added to docker group
# MUST already exist on the system
DOCKER_USER="hartings"
# ==================

echo "=== System update ==="
apt-get update -y
apt-get upgrade -y

echo "=== Installing prerequisites ==="
apt-get install -y --no-install-recommends \
  ca-certificates \
  curl \
  gnupg \
  lsb-release

echo "=== Configure Docker APT repository ==="
install -m 0755 -d /etc/apt/keyrings

curl -fsSL https://download.docker.com/linux/debian/gpg \
  | gpg --dearmor -o /etc/apt/keyrings/docker.gpg

chmod a+r /etc/apt/keyrings/docker.gpg

ARCH="$(dpkg --print-architecture)"
CODENAME="$(. /etc/os-release && echo "$VERSION_CODENAME")"

echo \
  "deb [arch=${ARCH} signed-by=/etc/apt/keyrings/docker.gpg] \
  https://download.docker.com/linux/debian \
  ${CODENAME} stable" \
  > /etc/apt/sources.list.d/docker.list

echo "=== Install Docker Engine and Compose ==="
apt-get update -y
apt-get install -y --no-install-recommends \
  docker-ce \
  docker-ce-cli \
  containerd.io \
  docker-buildx-plugin \
  docker-compose-plugin

echo "=== Enable Docker service ==="
systemctl enable docker
systemctl start docker

echo "=== Add user to docker group ==="
if id "${DOCKER_USER}" &>/dev/null; then
  usermod -aG docker "${DOCKER_USER}"
  echo "User '${DOCKER_USER}' added to docker group."
else
  echo "User '${DOCKER_USER}' does not exist — skipping group assignment."
fi

echo "=== Verifying installation ==="
docker --version
docker compose version

echo "=== Completed successfully ==="