You're reading from The Ultimate Docker Container Book Build, test, ship, and run containers with Docker and Kubernetes

Product type Paperback

Published in Aug 2023

Publisher Packt

ISBN-13 9781804613986

Length 626 pages

Edition 3rd Edition

Tools

Docker

Concepts

DevOps

Author (1):

Dr. Gabriel N. Schenker

View More author details

Table of Contents (26) Chapters

Preface

1. Part 1:Introduction

2. Chapter 1: What Are Containers and Why Should I Use Them? FREE CHAPTER

3. Chapter 2: Setting Up a Working Environment

4. Part 2:Containerization Fundamentals

5. Chapter 3: Mastering Containers

6. Chapter 4: Creating and Managing Container Images

7. Chapter 5: Data Volumes and Configuration

8. Chapter 6: Debugging Code Running in Containers

9. Chapter 7: Testing Applications Running in Containers

10. Chapter 8: Increasing Productivity with Docker Tips and Tricks

11. Part 3:Orchestration Fundamentals

12. Chapter 9: Learning about Distributed Application Architecture

13. Chapter 10: Using Single-Host Networking

14. Chapter 11: Managing Containers with Docker Compose

15. Chapter 12: Shipping Logs and Monitoring Containers

16. Chapter 13: Introducing Container Orchestration

17. Chapter 14: Introducing Docker Swarm

18. Chapter 15: Deploying and Running a Distributed Application on Docker Swarm

19. Part 4:Docker, Kubernetes, and the Cloud

20. Chapter 16: Introducing Kubernetes

21. Chapter 17: Deploying, Updating, and Securing an Application with Kubernetes

22. Chapter 18: Running a Containerized Application in the Cloud

23. Chapter 19: Monitoring and Troubleshooting an Application Running in Production

24. Index

Why subscribe?

25. Other Books You May Enjoy

Demystifying declarative versus imperative orchestration of containers

Docker Compose is a tool provided by Docker that is mainly used when you need to run and orchestrate containers running on a single Docker host. This includes, but is not limited to, development, continuous integration (CI), automated testing, manual QA, or demos. Since very recently, Docker Compose is embedded in the normal Docker CLI.

Docker Compose uses files formatted in YAML as input. By default, Docker Compose expects these files to be called docker-compose.yml, but other names are possible. The content of a docker-compose.yml file is said to be a declarative way of describing and running a containerized application potentially consisting of more than a single container.

So, what is the meaning of declarative?

First of all, declarative is the antonym of imperative. Well, that doesn’t help much. Now that I have introduced another definition, I need to explain both: