The Source-to-Image functionality of Red Hat OpenShift, an enterprise Kubernetes environment, is very useful and expedient. Simply point the runtime image of your choice (for example Node.js) at a GitHub repository that contains your code. With a few clicks, your resulting application is up and running. But for more complex applications, templating makes a deployment that contains multiple components just as easy to start up. Templating starts with base images and builds on them to create coherent applications.

This article examines how templating works, with examples on Red Hat OpenShift on IBM Cloud™. It examines Podman as a means to create the images that templates rely on.

The name Podman might sound a lot like something you use to play MP3s. In reality it is software that you can use to create or manage pods, containers, and container images — all without a container daemon.

The following graphic shows how pods, containers, and images work together:

In Kubernetes, you create pods on a particular node to host your application. Depending on your requirements, that pod consists of one or more containers. You run a container from a single image (which you create from instructions that provide an executable version of your application). Podman comes into play as the builder of your image.

You can read the full article on IBM Developer.