Book Image

The Docker Workshop

By : Vincent Sesto, Onur Yılmaz, Sathsara Sarathchandra, Aric Renzo, Engy Fouda
5 (1)
Book Image

The Docker Workshop

5 (1)
By: Vincent Sesto, Onur Yılmaz, Sathsara Sarathchandra, Aric Renzo, Engy Fouda

Overview of this book

No doubt Docker Containers are the future of highly-scalable software systems and have cost and runtime efficient supporting infrastructure. But learning it might look complex as it comes with many technicalities. This is where The Docker Workshop will help you. Through this workshop, you’ll quickly learn how to work with containers and Docker with the help of practical activities.? The workshop starts with Docker containers, enabling you to understand how it works. You’ll run third party Docker images and also create your own images using Dockerfiles and multi-stage Dockerfiles. Next, you’ll create environments for Docker images, and expedite your deployment and testing process with Continuous Integration. Moving ahead, you’ll tap into interesting topics and learn how to implement production-ready environments using Docker Swarm. You’ll also apply best practices to secure Docker images and to ensure that production environments are running at maximum capacity. Towards the end, you’ll gather skills to successfully move Docker from development to testing, and then into production. While doing so, you’ll learn how to troubleshoot issues, clear up resource bottlenecks and optimize the performance of services. By the end of this workshop, you’ll be able to utilize Docker containers in real-world use cases.
Table of Contents (17 chapters)
Preface

Configuration of Services

Cloud-native applications are expected to store their configuration in environment variables. Environment variables are easy to change between different platforms without source code changes. Environment variables are dynamic values that are stored in Linux-based systems and used by applications. In other words, the variables can be used to configure applications by changing their values.

For instance, assume your application uses a LOG_LEVEL environment variable to configure what is logged. If you change the LOG_LEVEL environment variable from INFO to DEBUG and restart your application, you would see more logs and be able to troubleshoot problems more easily. In addition, you can deploy the same application with different sets of environment variables to staging, testing, and production. Likewise, the method of configuring services in Docker Compose is to set environment variables for the containers.

There are three methods of defining environment...