plain.md

Plain Bundle Spec

Overview

This document is meant to define the plain bundle format as a reference for those publishing plain bundles for use with RukPak. For more information on the concept of a bundle, click here.

A plain bundle is simply a collection of static, arbitrary, Kubernetes YAML manifests in a given directory.

The currently implemented plain bundle format is the plain+v0 format. The name of the bundle format, plain+v0 combines the type of bundle (plain) with the current schema version (v0).

Note: the plain+v0 bundle format is at schema version v0, which means it's an experimental format that is subject to change.

Example

For example, below is an example of a file tree in a plain+v0 bundle. It must have a manifests directory contains the Kubernetes resources required to deploy an application.

manifests
├── namespace.yaml
├── cluster_role.yaml
├── role.yaml
├── serviceaccount.yaml
├── cluster_role_binding.yaml
├── role_binding.yaml
└── deployment.yaml

Note: there must be at least one resource in the manifests directory in order for the bundle to be a valid plain+v0 bundle.

Technical Details

• The static manifests must be located in the /manifests directory for the bundle to be a valid plain+v0 bundle that the provisioner can unpack. A plain bundle image without a /manifests directory is invalid and will not be successfully unpacked onto the cluster.
• The manifests directory should be flat: all manifests should be at the top-level with no subdirectories.
• Including any content in the /manifests directory of a plain bundle that is not static manifests will result in a failure when creating content on-cluster from that bundle. Essentially, any file that would not successfully kubectl apply will result in an error, but multi-object YAML files, or JSON files, are fine. There will be validation tooling provided that can determine whether a given artifact is a valid bundle.