While rewriting our k8s YAML files in ICL, we wanted to make it easier for everyone to write self-documented configuration files, files that exposes all the expected fields, what are they for ? and make it crystal clear for everyone what we are doing in our configuration files. Thanks to the work already done by @garethr we could write easily this simple program that generates k8s ICL templates right from kurberntes json schemas
All k8s ICL templates are written as mixins, this is for 2 main reasons :
- Readability : all the expected parameters are available and documented
- Easy to use : you just have to call the mixins and apply the necessary arguments and it's done.
Here is an example of the "Deployment" template
take deploymentstatus,
deploymentspec,
../v1/objectmeta
/**Deployment enables declarative updates for Pods and ReplicaSets.*/
::orch "kubernetes" "Deployment" as Deployment {
/**Kind is a string value representing the REST resource this object represents. Servers may
infer this from the endpoint the client submits requests to. Cannot be updated. In CamelCase.
More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#types-kinds*/
kind = "Deployment",
/**APIVersion defines the versioned schema of this representation of an object. Servers should
convert recognized schemas to the latest internal value, and may reject unrecognized values.
More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#resources*/
apiVersion = "v1beta1",
/**Most recently observed status of the Deployment.*/
DeploymentStatus "status" {}
/**Specification of the desired behavior of the Deployment.*/
DeploymentSpec "spec" {}
/**Standard object metadata.*/
ObjectMeta "metadata" {}
}
And here is how you can call it
take github.com/k8s-icl/latest/v1beta1/deployment,
github.com/k8s-icl/latest/v1/containerport,
github.com/k8s-icl/latest/v1/container
::variable "container-port" apply ContainerPort @@name="nginx", @@containerPort="8080"
::variable "container-ports" [variable.container-port]
::variable "container" apply Container @@image="nginx:1.13.0", @@name="nginx", @@ports=variable.container-ports
::variable "container-list" [variable.container]
::variable "pod-spec" apply PodSpec @@containers=variable.container-list
::variable "labels" table "app" = "nginx"
::variable "pod-metadata" apply ObjectMeta @@labels=variable.labels
::variable "template" apply PodTemplateSpec @@spec=variable.pod-spec, @@metadata=variable.pod-metadata
::variable "spec" apply DeploymentSpec @@replicas=5, @@template=variable.template
::variable "metadata" apply ObjectMeta @@name = "nginx"
_ "_" apply Deployment @@metadata=variable.metadata, @@spec=variable.spec
You can use the already generated templates directly, but if you want to regenerate them, you just have to perform a npm start, the program will fetch all the kubernetes schemas for the different versions and regenerate ICLs templates.