Docker Compose is a tool for defining and running multi-container Docker applications. It allows developers to define the services that make up their application and how they interact with each other, all in a single file. In this article, we’ll cover everything you need to know to get started with creating a Docker Compose file, including examples of how to define services and configure networking.
Before we dive into creating a Docker Compose file, let’s make sure you have the necessary prerequisites:
- Have Docker installed
- Have a basic knowledge of Docker: Familiarize yourself with Docker and its concepts
How to Create a Docker Compose File
A Docker Compose file is a YAML file that defines the services, networks, and volumes for your Docker application.
The beginning of a Compose file always starts with the
version key. This key is used to specify the version of the Docker Compose syntax being used in the file. This is important because Docker Compose has gone through several major revisions, and each revision introduces new features or changes to the syntax.
Currently, the latest version of the Docker Compose syntax is version 3.9. When you specify the version tag as “3.9”, Docker Compose will use the latest syntax and recognize all of the latest features and syntax changes.
After defining the version of the Compose file it’s time to define the services that will be run in the containers.