Setting Up a Working Environment

In the last chapter, we learned what Docker containers are and why they're important. We learned what kinds of problems containers solve in a modern software supply chain.

In this chapter, we are going to prepare our personal or working environment to work efficiently and effectively with Docker. We will discuss in detail how to set up an ideal environment for developers, DevOps, and operators that can be used when working with Docker containers.

This chapter covers the following topics:

• The Linux command shell
• PowerShell for Windows
• Installing and using a package manager
• Installing Git and cloning the code repository
• Choosing and installing a code editor
• Installing Docker for Desktop on macOS or Windows
• Installing Docker Toolbox
• Installing Minikube

Technical requirements

For this chapter, you will need a laptop or a workstation with either macOS or Windows, preferably Windows 10 Professional, installed. You should also have free internet access to download applications and permission to install those applications on your laptop.

It is also possible to follow along with this book if you have a Linux distribution as your operating system, such as Ubuntu 18.04 or newer. I will try to indicate where commands and samples differ significantly from the ones on macOS or Windows.

The Linux command shell

Docker containers were first developed on Linux for Linux. It is hence natural that the primary command-line tool used to work with Docker, also called a shell, is a Unix shell; remember, Linux derives from Unix. Most developers use the Bash shell. On some lightweight Linux distributions, such as Alpine, Bash is not installed and consequently one has to use the simpler Bourne shell, just called sh. Whenever we are working in a Linux environment, such as inside a container or on a Linux VM, we will use either /bin/bash or /bin/sh, depending on their availability.

Although Apple's macOS X is not a Linux OS, Linux and macOS X are both flavors of Unix and hence support the same set of tools. Among those tools are the shells. So, when working on macOS, you will probably be using the Bash shell.

In this book,...

PowerShell for Windows

On a Windows computer, laptop, or server, we have multiple command-line tools available. The most familiar is the command shell. It has been available on any Windows computer for decades. It is a very simple shell. For more advanced scripting, Microsoft has developed PowerShell. PowerShell is very powerful and very popular among engineers working on Windows. On Windows 10, finally, we have the so-called Windows Subsystem for Linux, which allows us to use any Linux tool, such as the Bash or Bourne shells. Apart from this, there are also other tools that install a Bash shell on Windows, for example, the Git Bash shell. In this book, all commands will use Bash syntax. Most of the commands also run in PowerShell.

Our recommendation for you is hence to either use PowerShell or any other Bash tool to work with Docker on Windows.

...

Using a package manager

The easiest way to install software on a macOS or Windows laptop is to use a good package manager. On macOS, most people use Homebrew, and on Windows, Chocolatey is a good choice. If you're using a Debian-based Linux distribution such as Ubuntu, then the package manager of choice for most is apt, which is installed by default. 

Installing Homebrew on macOS

Homebrew is the most popular package manager on macOS, and it is easy to use and very versatile. Installing Homebrew on macOS is simple; just follow the instructions at https://brew.sh/:

1. In a nutshell, open a new Terminal window and execute the following...

Installing Git

We are using Git to clone the sample code accompanying this book from its GitHub repository. If you already have Git installed on your computer, you can skip this section:

1. To install Git on your macOS, use the following command in a Terminal window:

$ choco install git

2. To install Git on Windows, open a PowerShell window and use Chocolatey to install it:

PS> choco install git -y

3. Finally, on your Debian or Ubuntu machine, open a Bash console and execute the following command:

$ sudo apt update && sudo apt install -y git

4. Once Git is installed, verify that it is working. On all platforms, use the following:

$ git --version

This should output something along the lines of the following:

git version 2.16.3

5. Now that Git is working, we can clone the source code accompanying this book from GitHub. Execute the following command:

$ cd ~
$ git clone https...

Choosing a code editor

Using a good code editor is essential to working productively with Docker. Of course, which editor is the best is highly controversial and depends on your personal preference. A lot of people use Vim, or others such as Emacs, Atom, Sublime, or Visual Studio Code (VS Code), to just name a few. VS Code is a completely free and lightweight editor, yet it is very powerful and is available for macOS, Windows, and Linux. According to Stack Overflow, it is currently by far the most popular code editor. If you are not yet sold on another editor, I highly recommend that you give VS Code a try.

But if you already have a favorite code editor, then please continue using it. As long as you can edit text files, you're good to go. If your editor supports syntax highlighting for Dockerfiles and JSON and YAML files, then even better...

Installing Docker for Desktop

If you are using macOS or have Windows 10 Professional installed on your laptop, then we strongly recommend that you install Docker for Desktop. This platform gives you the best experience when working with containers.

Docker for Desktop is not supported on Linux at this time. Please refer to the Installing Docker CE on Linux section for more details.

Note that older versions of Windows or Windows 10 Home edition cannot run Docker for Windows. Docker for Windows uses Hyper-V to run containers transparently in a VM but Hyper-V is not available on older versions of Windows; nor is it available in the Home edition of Windows 10. In this case, we recommend that you use Docker Toolbox instead, which we will describe in the next section.

 Follow these steps:

1. No matter what OS you're using, navigate to the Docker...

Installing Docker Toolbox

Docker Toolbox has been available for developers for a few years. It precedes newer tools such as Docker for Desktop. The Toolbox allows a user to work very elegantly with containers on any macOS or Windows computer. Containers must run on a Linux host. Neither Windows nor macOS can run containers natively. Hence, we need to run a Linux VM on our laptop, where we can then run our containers. Docker Toolbox installs VirtualBox on our laptop, which is used to run the Linux VMs we need.

As a Windows user, you might already be aware that there are so-called Windows containers that run natively on Windows, and you are right. Microsoft has ported Docker Engine to Windows and it is possible to run Windows containers directly on Windows Server 2016 or newer, without the need for a VM. So, now we have two flavors of containers, Linux containers and Windows...

Installing Minikube

If you cannot use Docker for Desktop or, for some reason, you only have access to an older version of the tool that does not yet support Kubernetes, then it is a good idea to install Minikube. Minikube provisions a single-node Kubernetes cluster on your workstation and is accessible through kubectl, which is the command-line tool used to work with Kubernetes.

Installing Minikube on macOS and Windows

To install Minikube for macOS or Windows, navigate to the following link: https://kubernetes.io/docs/tasks/tools/install-minikube/.

Follow the instructions carefully. If you have Docker Toolbox installed, then you already have a hypervisor on your system since the...

Summary

In this chapter, we set up and configured our personal or working environment so that we can productively work with Docker containers. This equally applies for developers, DevOps, and operations engineers. In that context, we make sure that we use a good editor, have Docker for macOS or Docker for Windows installed, and can use docker-machine to create VMs in VirtualBox or Hyper-V, which we can then use to run and test containers.

In the next chapter, we're going to learn all of the important facts about containers. For example, we will explore how we can run, stop, list, and delete containers, but more than that, we will also dive deep into the anatomy of containers. 

Questions

Based on your reading of this chapter, please answer the following questions:

1. What is docker-machine used for? Name three to four scenarios.
2. With Docker for Windows, you can develop and run Linux containers.

A. True
B. False

3. Why are good scripting skills (such as Bash or PowerShell) essential for the productive use of containers?
4. Name three to four Linux distributions on which Docker is certified to run.
5. Name all of the Windows versions on which you can run Windows containers.

Further reading

Consider the following links for further reading:

• Chocolatey - The Package Manager for Windows at https://chocolatey.org/
• Install Docker Toolbox on Windows: https://dockr.ly/2nuZUkU
• Run Docker on Hyper-V with Docker Machine at http://bit.ly/2HGMPiI
• Developing inside a Container at https://code.visualstudio.com/docs/remote/containers