README.md

Kubernetes WarmImage CRD.

Overview

This repository defines a Kubernetes "Custom Resource Definition" (CRD) called WarmImage. The WarmImage CRD takes an image reference (with optional secrets) and prefetches it onto every node in your cluster.

Cluster Setup

It is recommended that folks install this into its own namespace.

To install this custom resource onto your cluster, you may simply run:

# Install the CRD and Controller.
curl https://raw.githubusercontent.com/mattmoor/warm-image/master/release.yaml \
  | kubectl create -f -

Alternately you may git clone this repository and run:

# Install the CRD and Controller.
kubectl create -f release.yaml

Uninstall

Simply use the same command you used to install, but with kubectl delete instead of kubectl create.

Usage

Specification

The specification for an image to "warm up" looks like:

apiVersion: mattmoor.io/v2
kind: WarmImage
metadata:
  name: example-warmimage
spec:
  image: gcr.io/google-appengine/debian8:latest
  # Optionally:
  # imagePullSecrets: 
  # - name: foo

Creation

With the above in foo.yaml, you would install the image with:

kubectl create -f foo.yaml

Listing

You can see what images are "warm" via:

$ kubectl get warmimages
NAME                KIND
example-warmimage   WarmImage.v2.mattmoor.io

Updating

You can upgrade foo.yaml to debian9 and run:

kubectl replace -f foo.yaml

Removing

You can remove a warmed image via:

kubectl delete warmimage example-warmimage