Kubernetes Operator which allows you to update ConfigMaps, based on some external URL/filepath which serves the required data.
⚠ This project is made for learning/experimentation purposes and config can change at any time. Ideally, you can replicate similar functionality via other standard configuration practices.
usage: configmap-operator run [<flags>]
Launches ConfigMap Operator
Flags:
-h, --help Show context-sensitive help (also try --help-long
and --help-man).
--version Show application version.
--log.level=info Log filtering level.
--log.format=clilog Log format to use.
--metrics="metrics" Endpoint for serving metrics.
--kubeconfig=KUBECONFIG Path to a kubeconfig. Only required if
out-of-cluster.
--master=MASTER The address of the Kubernetes API server.
Overrides any value in kubeconfig. Only required
if out-of-cluster.
--namespace="default" The namespace to watch.
--refresh.interval=10s The interval after which the ConfigMap will be
refreshed.
Example manifests are provided here and are generated with jsonnet!
Spin-up a cluster with kind and create a configmap-operator-demo namespace,
kubectl apply -f examples/manifests/namespace.yamlDeploy the configmap-operator,
kubectl apply -f examples/manifests/This creates the ConfigMap below with an empty data field and the annotations configmap-operator-src and configmap-operator-key which will be used by the operator to fill in data.
apiVersion: v1
kind: ConfigMap
metadata:
annotations:
configmap-operator-key: prom.yaml
configmap-operator-src: https://raw.githubusercontent.com/prometheus/prometheus/main/documentation/examples/prometheus.yml
labels:
app.kubernetes.io/component: kubernetes-operator
app.kubernetes.io/instance: configmap-operator
app.kubernetes.io/name: configmap-operator
name: example-prom-config
namespace: configmap-operator-demoThe operator is deployed with the Deployment below and its related RoleBinding and ServiceAccount. It finds ConfigMaps with the above annotations and starts updating it periodically (15s)
apiVersion: apps/v1
kind: Deployment
metadata:
labels:
app.kubernetes.io/component: kubernetes-operator
app.kubernetes.io/instance: configmap-operator
app.kubernetes.io/name: configmap-operator
name: configmap-operator
namespace: configmap-operator-demo
spec:
replicas: 1
selector:
matchLabels:
app.kubernetes.io/component: kubernetes-operator
app.kubernetes.io/instance: configmap-operator
app.kubernetes.io/name: configmap-operator
template:
metadata:
labels:
app.kubernetes.io/component: kubernetes-operator
app.kubernetes.io/instance: configmap-operator
app.kubernetes.io/name: configmap-operator
spec:
containers:
- args:
- run
- --log.level=info
- --log.format=json
- --refresh.interval=15s
- --namespace=$(NAMESPACE)
env:
- name: NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
image: saswatamcode/configmap-operator
imagePullPolicy: IfNotPresent
name: configmap-operator
ports:
- containerPort: 9090
resources: {}
serviceAccount: configmap-operator-saWatch the ConfigMap for changes and see the data field get populated with a prom.yaml sample Prometheus config.
watch kubectl get configmap example-prom-config --namespace configmap-operator-demo -o yaml Initially inspired by cloud-native-skunkworks/cnskunkworks-operator!
