Review Project

Let’s review the resources.

Namespace

We’ll create a namespace for the app resources:

.kubes/resources/shared/namespace.rb

name "demo-#{Kubes.env}"
labels(app: "demo")

Notice, the #{Kubes.env}. Kubes adds the env to the namespace by default. You can change this with the init --namespace option.

Deployment

The web/deployment.rb file is a little more interesting:

.kubes/resources/web/deployment.rb

name "demo-web"
labels(role: "web")
namespace "default"

replicas 1
image built_image # IE: user/demo:kubes-2020-06-13T19-55-16-43afc6e

The DSL form is more concise than the YAML form. Also, notice the use of the built_image helper. The built_image is a kubes helper method that refers to the latest Docker image built. This spares you from updating the image manually.

Base Folder

Also let’s check the files in the base folder.

.kubes/resources/base/all.rb

namespace "demo-#{Kubes.env}"
labels(app: "demo")

The base folder files are processed first as a part of Kubes Layering. This allows you to define common fields and keep your code DRY.

Next, let’s look at service.rb

.kubes/resources/web/service.rb

name "demo-web"
labels(role: "web")

# Optional since default port is 80
# port 80
# targetPort 80

Service is also pretty simple. Though the DSL may seem simple, it allows you to fully control the generated YAML. You can learn more about the DSL form at: Deployment DSL Docs

Next, we’ll deploy the app.