Kubectl kustomize

External

• https://kubernetes.io/blog/2018/05/29/introducing-kustomize-template-free-configuration-customization-for-kubernetes/
• https://github.com/kubernetes-sigs/kustomize

Internal

• kubectl

Overview

The "kustomize" logic reads a series of source API resource manifests, instructions from a kustomization.yaml file and generates syntactically valid and complete API resource manifests at stdout. The generated content may contain multiple resource representations, separated by ---. The output can be further processed by other tools or streamed directly into kubectl for deployment to a cluster.

kubectl kustomize <dirname> > output.yaml

The directory specified as argument must contain kustomization.yaml.

A kustomization.yaml example follows:

# add the specified labels to all resources
commonLabels:
  app: hello
# add the specified annotations to all resources
commonAnnotations:
  ...
# add the specified common prefix to all resource names
namePrefix: blue-
resources:
- deployment-manifest.yaml
- configmap-manifest.yaml
- service-manifest.yaml

kustomization.yaml Example

images:
- name: something
  newTag: ...
namespace: ...   
patchesStrategicMerge:
- file1.yaml

TODO

It seems to add prefixes to names, update image tags, adds namespace metadata, "yaml-cleans" according to rules that have yet to be elucidated.