imageTags.md

Demo: change image tags

Define a place to work:

DEMO_HOME=$(mktemp -d)

Make a kustomization containing a pod resource

cat <<EOF >$DEMO_HOME/kustomization.yaml
resources:
- pod.yaml
EOF

Declare the pod resource

cat <<EOF >$DEMO_HOME/pod.yaml
apiVersion: v1
kind: Pod
metadata:
  name: myapp-pod
  labels:
    app: myapp
spec:
  containers:
  - name: myapp-container
    image: busybox:1.29.0
    command: ['sh', '-c', 'echo The app is running! && sleep 3600']
  initContainers:
  - name: init-mydb
    image: busybox:1.29.0
    command: ['sh', '-c', 'until nslookup mydb; do echo waiting for mydb; sleep 2; done;']
EOF

The myapp-pod resource declares an initContainer and a container, both use the image busybox:1.29.0. The tag 1.29.0 can be changed by adding imageTags in kustomization.yaml.

Add imageTags:

cd $DEMO_HOME
kustomize edit set imagetag busybox:1.29.1

The kustomization.yaml will be added following imageTags.

imageTags:
- name: busybox
  newTag: 1.29.1

Now build this kustomization

kustomize build $DEMO_HOME

Confirm that this replaces both busybox tags:

test 2 == \
  $(kustomize build $DEMO_HOME | grep busybox:1.29.1 | wc -l); \
  echo $?