sablier/docs/providers/kubernetes.md

Kubernetes

Sablier assumes that it is deployed within the Kubernetes cluster to use the Kubernetes API internally.

Use the Kubernetes provider

In order to use the kubernetes provider you can configure the provider.name property.

File (YAML)

provider:
  name: kubernetes

CLI

sablier start --provider.name=kubernetes

Environment Variable

PROVIDER_NAME=kubernetes

!> Ensure that Sablier has the necessary roles!

apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: sablier
rules:
  - apiGroups:
      - apps
      - ""
    resources:
      - deployments
      - statefulsets
    verbs:
      - get     # Retrieve info about specific dep
      - list    # Events
      - watch   # Events
  - apiGroups:
      - apps
      - ""
    resources:
      - deployments/scale
      - statefulsets/scale
    verbs:
      - patch   # Scale up and down
      - update  # Scale up and down
      - get     # Retrieve info about specific dep
      - list    # Events
      - watch   # Events

Register Deployments

For Sablier to work, it needs to know which deployments to scale up and down.

You have to register your deployments by opting-in with labels.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: whoami
  labels:
    app.kubernetes.io/name: whoami
    sablierapp.dev/enable: "true"
    sablierapp.dev/group: mygroup
spec:
  selector:
    matchLabels:
      app.kubernetes.io/name: whoami
  template:
    metadata:
      labels:
        app.kubernetes.io/name: whoami
    spec:
      containers:
      - name: whoami
        image: acouvreur/whoami:v1.10.2

How does Sablier knows when a deployment is ready?

Sablier checks for the deployment replicas. As soon as the current replicas matches the wanted replicas, then the deployment is considered ready.

?> Kubernetes uses the Pod healthcheck to check if the Pod is up and running. So the provider has a native healthcheck support.