Install Docker on Debian 11 Bullseye (one line)

docker-debian-11.sh

#!/bin/bash
#
# Install docker on Debian 11 Bullseye with one line
#

set -u;

# Check if user is root.
[[ ! $(id -u) -eq 0 ]] && echo "Run as root." && exit 1;

# Uninstall old versions
apt remove docker docker-engine docker.io containerd runc 2>/dev/null;

# Set up the repository
# 1. Update the apt package index and install packages to allow apt to use a repository over HTTPS:
apt update;
sudo apt-get install \
    ca-certificates \
    curl \
    gnupg \
    lsb-release;

# 2. Add Docker’s official GPG key:
mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/debian/gpg | gpg --dearmor -o /etc/apt/keyrings/docker.gpg;

# 3. Use the following command to set up the repository:
echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.gpg] https://download.docker.com/linux/debian \
  $(lsb_release -cs) stable" | tee /etc/apt/sources.list.d/docker.list > /dev/null;

# Install Docker Engine
apt update;
apt install docker-ce docker-ce-cli containerd.io docker-compose-plugin;

# done.