Book Image

Docker for Developers

By : Richard Bullington-McGuire, Andrew K. Dennis, Michael Schwartz
2 (1)
Book Image

Docker for Developers

2 (1)
By: Richard Bullington-McGuire, Andrew K. Dennis, Michael Schwartz

Overview of this book

Docker is the de facto standard for containerizing apps, and with an increasing number of software projects migrating to containers, it is crucial for engineers and DevOps teams to understand how to build, deploy, and secure Docker environments effectively. Docker for Developers will help you understand Docker containers from scratch while taking you through best practices and showing you how to address security concerns. Starting with an introduction to Docker, you’ll learn how to use containers and VirtualBox for development. You’ll explore how containers work and develop projects within them after you’ve explored different ways to deploy and run containers. The book will also show you how to use Docker containers in production in both single-host set-ups and in clusters and deploy them using Jenkins, Kubernetes, and Spinnaker. As you advance, you’ll get to grips with monitoring, securing, and scaling Docker using tools such as Prometheus and Grafana. Later, you’ll be able to deploy Docker containers to a variety of environments, including the cloud-native Amazon Elastic Kubernetes Service (Amazon EKS), before finally delving into Docker security concepts and best practices. By the end of the Docker book, you’ll be able to not only work in a container-driven environment confidently but also use Docker for both new and existing projects.
Table of Contents (21 chapters)
1
Section 1: An Introduction to Docker – Containers and Local Development
6
Section 2: Running Docker in Production
14
Section 3: Docker Security – Securing Your Containers

Implementing a sample microservices application

We can use the Mosca, MongoDB, and Redis containers, along with a couple of custom containers, to implement a simple but complete application:

Figure 3.3 – Diagram of our sample microservices application

Figure 3.3 – Diagram of our sample microservices application

The publisher and subscriber will communicate with each other using MQTT. The subscriber will listen for a handful of MQTT topics that direct it to operate on or retrieve information from the MongoDB and Redis databases. The publisher will send these MQTT topics and print the responses.

The publisher will be based on Node.js version 11 and the subscriber will be based on Node.js version 12. Without Docker or a virtual machine, running two Node.js versions on the same machine concurrently requires the use of Node Version Manager (nvm) and having multiple versions of Node.js installed on your workstation. Docker containers make it simple to use as many versions as you need and to package the version...