ahmadidev / k8s-util

bitnami kubectl image with helm and gettext package included

k8s-util - bitnami kubectl image with helm and gettext package included

If you use helm to deploy some application dependecies like MongoDB or MySQL in a GitOps fashion, and use environment variables in your k8s manifests to easily manage multiple projects, you may need a docker image with kubectl, helm, and gettext tools included.

Two common scenarios in my setups is similar to following codes:

1- Deploy application kubernetes manifests with a lot of environment variables

manifests.yaml:

apiVersion: v1
kind: Namespace
metadata:
  name: $KUBE_NAMESPACE
---
apiVersion: apps/v1
kind: Deployment
metadata: 
  name: $CI_PROJECT_NAME
spec:
  replicas: 1
  selector:
    matchLabels:
      name: $CI_PROJECT_NAME
  template:
    metadata:
      labels:
        name: $CI_PROJECT_NAME
    spec:
      containers:
        - name: $CI_PROJECT_NAME
          image: $CI_REGISTRY/$CI_PROJECT_NAMESPACE/$CI_PROJECT_NAME:$CI_COMMIT_SHORT_SHA
          ports:
            - name: http
              containerPort: 8080
              protocol: TCP
---
apiVersion: v1
kind: Service
metadata:
  name: $CI_PROJECT_NAME
spec:
  selector:
    name: $CI_PROJECT_NAME
  ports:
  - port: 80
    name: http
    targetPort: http
---
apiVersion: networking.k8s.io/v1 
kind: Ingress
metadata:
  name: $CI_PROJECT_NAME
spec:
  rules:
  - host: $INGRESS_HOST
    http:
      paths:
      - backend:
          service: 
            name: $CI_PROJECT_NAME
            port: 
              name: http
        path: $INGRESS_PATH
        pathType: ImplementationSpecific

.gitlab-ci.yml file:

deploy:
  image:
    name: ghcr.io/ahmadidev/k8s-util
    entrypoint: ['']
  variables:
    KUBE_NAMESPACE: "$CI_PROJECT_NAME-$CI_ENVIRONMENT_NAME"
    INGRESS_HOST: app.domain.tld
    INGRESS_PATH: /
  script:
    - echo "Deploying manifests under $KUBE_NAMESPACE namespace"
    - envsubst < ./manifests.yaml | kubectl apply -f - -n $KUBE_NAMESPACE

As you can see, you are free to use all possible envs that are passed by CI engine or defined by you with envsust tool which is included in the k8s-util image. Using env vars, you can easily copy just this two file over other projects and have CICD enabled in no time.

2- Deploy application dependencies helm charts

mongodb-helm-values.yaml:

auth:
  usernames:
  - api
  passwords:
  - api-secret-pass
  databases:
  - app

.gitlab-ci.yml file:

config:
  image: 
    name: ghcr.io/ahmadidev/k8s-util
    entrypoint: ['']
  variables:
    KUBE_NAMESPACE: "$CI_PROJECT_NAME-$CI_ENVIRONMENT_NAME"
    HELM_CONFIG_HOME: /tmp/.helm-config/
    HELM_DATA_HOME: /tmp/.helm-data/
    HELM_CACHE_HOME: /tmp/.helm-cache/
  script:
    # KUBECONFIG file is mounted from gitlab-runner to the container
    - helm version
    - helm repo add bitnami https://charts.bitnami.com/bitnami
    - helm upgrade --install mongodb bitnami/mongodb --namespace=$KUBE_NAMESPACE --create-namespace --version=13.10.1 --values=mongodb-helm-values.yaml

In this setup you only need a docker executor runner and this image to easily deploy and manage your application dependencies.