doc/tutorial/kubernetes/quick/services/kube.cue

package kube

service: [ID=_]: {
	apiVersion: "v1"
	kind:       "Service"
	metadata: {
		name: ID
		labels: {
			app:       ID        // by convention
			domain:    "prod"    // always the same in the given files
			component: Component // varies per directory
		}
	}
	spec: {
		// Any port has the following properties.
		ports: [...{
			port:     int
			protocol: *"TCP" | "UDP" // from the Kubernetes definition
			name:     string | *"client"
		}]
		selector: metadata.labels // we want those to be the same
	}
}

deployment: [ID=_]: {
	apiVersion: "apps/v1"
	kind:       "Deployment"
	metadata: name: ID
	spec: {
		// 1 is the default, but we allow any number
		replicas: *1 | int
		template: {
			metadata: labels: {
				app:       ID
				domain:    "prod"
				component: Component
			}
			// we always have one namesake container
			spec: containers: [{name: ID}]
		}
	}
}

Component :: string

daemonSet: [ID=_]: _spec & {
	apiVersion: "apps/v1"
	kind:       "DaemonSet"
	Name ::     ID
}

statefulSet: [ID=_]: _spec & {
	apiVersion: "apps/v1"
	kind:       "StatefulSet"
	Name ::     ID
}

deployment: [ID=_]: _spec & {
	apiVersion: "apps/v1"
	kind:       "Deployment"
	Name ::     ID
	spec: replicas: *1 | int
}

configMap: [ID=_]: {
	metadata: name: ID
	metadata: labels: component: Component
}

_spec: {
	Name :: string

	metadata: name: Name
	metadata: labels: component: Component
	spec: selector: {}
	spec: template: {
		metadata: labels: {
			app:       Name
			component: Component
			domain:    "prod"
		}
		spec: containers: [{name: Name}]
	}
}

// Define the _export option and set the default to true
// for all ports defined in all containers.
_spec: spec: template: spec: containers: [...{
	ports: [...{
		_export: *true | false // include the port in the service
	}]
}]

for x in [deployment, daemonSet, statefulSet] for k, v in x {
	service: "\(k)": {
		spec: selector: v.spec.template.metadata.labels

		spec: ports: [ {
			Port = p.containerPort // Port is an alias
			port:       *Port | int
			targetPort: *Port | int
		} for c in v.spec.template.spec.containers
			for p in c.ports
			if p._export ]
	}
}