Creating a Docker container action

In this recipe, you will create a simple Docker container action from a Dockerfile and use it in a continuous integration (CI) workflow that will run the action from within the workflow every time you change something.

Getting ready…

Create a new repository called DockerActionRecipe. Make it public so that you don’t consume any action minutes and initialize it with a README file (see Figure 3.1):

Figure 3.1 – Creating a new repository for the Docker container action

Clone the repository locally and open it in VS Code or GitHub Codespaces.

How to do it…

1. Create a new file called Dockerfile in the root of the repository. Add the following content to the file:

   # Container image that runs your code
   FROM alpine:latest
   CMD echo "Hello World"

   This will create an image based on the latest Alpine image and add a layer that writes “Hello World” to the console.

...