A boiler script for Ubuntu 16.04 (x86_64) to install Docker-ce.

docker-ce-install.sh

#!/usr/bin/env bash

#####################
# OS: Ubuntu 16.04  #
# H/W: x86_64       #
#####################

# Uninstall old versions
sudo apt-get remove docker docker-engine docker.io

# Update the apt package index
sudo apt-get update

# Install packages to allow apt to use a repository over HTTPS
sudo apt-get install -y \
    apt-transport-https \
    ca-certificates \
    curl \
    software-properties-common

# Add Docker’s official GPG key
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -

# Set up the stable repository
sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
   $(lsb_release -cs) \
   stable"

# Update the apt package index again
sudo apt-get update

# Install Docker CE
sudo apt-get install -y docker-ce

Install Docker CE with the following command.

curl -sL "https://gist.githubusercontent.com/momocow/2ab83c4ee513f8ec80c56fb6d08742be/raw/docker-ce-install.sh" | sudo bash -

Reference
https://docs.docker.com/install/linux/docker-ce/ubuntu