KOM Operator

The Kubernetes Operator for Microservices aka KOM Operator, is designed to manage all the lifecycle of a HTTP based microservice including deploying/updating, load balancing and auto scaling.

The KOM Operator is using these services under the hood to manage deployments:

• Traefik proxy for load balancing
• The kubernate horizontal pod autoscaler for autoscaling.

Quick start

Install

The KOM Operator can be installed through many ways:

• Helm: see instructions here
• Olm (Deprecated): see instructions here

Use the KOM Operator:

In order to deploy your microservice using the KOM Operator simply create a yaml descriptor file, the following example deploys nginx. routing, volumes & autoscaling are optional.

apiVersion: kom.kaiso.github.io/v1alpha1
kind: Microservice
metadata:
    name: kom-nginx
    namespace: default
    labels:
        deploymentName: kaiso-nginx
spec:
  nodeSelector:
    kubernetes.io/os: linux
  container:
    image: nginx:latest
    args:
        - 'nginx-debug'
        -  '-g'
        - 'daemon off;'
    routing:
          http:
            - port: 
                containerPort: 8019
                name: "https"
              rule: "PathPrefix(`/nginxhttps`)"
            - port: 
                containerPort: 80
                name: "http"
              rule: "Host(`nginx.kaiso.local`)"
    volumeMounts:
            - mountPath: /var/log/
              name: logvolume
            - mountPath: /usr/share/nginx/html/
              name: contentvolume
    resources:
      requests:
          memory: 50Mi
          cpu: 100m
      limits:
          memory: 200Mi
          cpu: 500m
  autoscaling:
      min: 2
      max: 5
      scaler:
          - resource: CPU
            type: Utilization
            value: "75"
  volumes:
      - name: logvolume
        hostPath:
            path: /Volumes/DATA/tmp/log/
            type: DirectoryOrCreate
      - name: contentvolume
        hostPath:
            path: /Volumes/DATA/tmp/mdrn/engine/buildprod/
            type: DirectoryOrCreate

Check the created objects:

 kubectl get pods
 kubectl get hpa

Go to your browser to see if the routing was applied on http://localhost/web

Development

Local run

To run the operator locally outside the cluster

# Install CRDs
make install
# run locally
make run

Uninstall CRDs

make uninstall

Release

Update Version

the version must be updated in three files:

• version/version.go
• Makefile
• helm/kom/operator/Chart.yaml

Build docker image

  make docker-build

Install helm chart locally

  cd helm
  helm lint kom-operator
  helm install --set loadbalancer.replicaCount=2 kom-operator ./kom-operator

Build helm chart

  cd helm
  helm lint kom-operator
  helm package kom-operator