Slack Notification#

This feature will be supported from v0.8.0 onwards.
Kubesaver can be configured to notify the resources defined in rules when they are scaled down and scaled up
Every rule in rules can be configured to alert to unique slack channel. This gives the flexibilty to notify the owners of the resources.

Configuring slack app and token#

Create slack app and configure the Workspace. Follow the guidelines: https://api.slack.com/apps
In Add features and functionality, Select Permissions and set the Scopes by clicking Add an OAuth Scope
Select Bot User OAuth Token
Select chat:write permission to write chat to workspace and files:write for uploading the files.
Copy the token(xoxb-....) which will be uploaded as a Kubernetes secret in the Cluster.

Kubernetes manifest#

Mount the slack token as a file in the path /var/slack_token reference: Secret as file
Or
Set slack token as a Environment Variable SLACK_API_TOKEN using Kubernetes secret: Secret as evn
Store the secret in Google GSM or AWS Secret Manager and use Kubernetes Secrets CSI Driver to get the secret and mount the secret as a volume to the Deployment manifest

Configurations & Installation#

Create Slack Token Secret

echo -n 'xoxb-xxx' > ./slack.txt
kubectl create secret generic slack-token --from-file=./slack.txt --namespace kube-saver

Update rules.yaml

rules:
  - id: rules-downscale-kuber1
    uptime: Mon-Sun 22:59-23:00 Australia/Sydney
    jmespath: "metadata.name == 'kuber1'"
    resource:
      - Namespace
    slack_channel: C040RXXXXXX
    replicas: 0
  - id: rules-downscale-kuber2
    uptime: Mon-Sun 00:00-23:59 Australia/Sydney # all up
    jmespath: "metadata.name == 'kuber2'"
    resource:
      - Namespace
    replicas: 0
    slack_channel: C040RYYYYYY

Update the deployment manifest in k8s/install.yaml

# slack token as a file
apiVersion: apps/v1
kind: Deployment
metadata:
  namespace: kube-saver
  name: kube-saver-operator
  labels:
    app: kube-saver-operator
spec:
  replicas: 1
  selector:
    matchLabels:
      app: kube-saver-operator
  template:
    metadata:
      labels:
        app: kube-saver-operator
    spec:
      serviceAccountName: kube-saver
      containers:
        - name: kube-saver-operator
          image: maheshrayas/kube-saver:v0.8.0
          args:
            - "--rules=/config/rules.yaml" #rules for downscale
            - "--interval=60" # every 60 secs, the controller will check the resources to downscale or upscale
            - "--debug" # remove to set log as INFO
            - "--comm-type=slack" # notification type is slack, pass this arg if you want notified to slack
            - "--comm-details=<slackworkspace>" # slack workspace name, pass this arg if comm-type is set to slack
          resources:
            limits:
              cpu: "1"
              memory: 500Mi
            requests:
              cpu: "0.5"
              memory: 100Mi
          imagePullPolicy: Always
          securityContext:
            allowPrivilegeEscalation: false
            capabilities:
              drop:
                - ALL
            readOnlyRootFilesystem: false # Create tmp file for slack notification
            runAsGroup: 1001
            runAsNonRoot: true
            runAsUser: 1001
            seccompProfile:
              type: RuntimeDefault
          volumeMounts:
            - name: config-volume
              mountPath: /config
            - name: slack-api-token
              mountPath: "/var/slack_token"
              readOnly: true
            - mountPath: /tmp
              name: tmp-volume
      volumes:
        - name: tmp-volume
          emptyDir: {}
        - name: config-volume
          configMap:
            name: rules
        - name: slack-api-token
          secret:
            secretName: slack-token
            optional: false # default setting; "slack-token" must exist

Install

  kubectl apply -k k8s/