One Deployment Per branch, plus CI CD, gitlab and helm setup

.gitlab-ci.yml

image: docker.mydomain.com/build/kube-go-make

variables:
  DOCKER_TAG: docker.mydomain.com/myapp/home:$CI_COMMIT_REF_SLUG
  DOCKER_HOST: tcp://localhost:2375
  DOCKER_DRIVER: overlay
  PROD_RSYNC_HOST: myprodserver.com
  DOMAIN: mydomain.com
  CHART_DIR: chart

stages:
  - web
  - dockerize
  - ci
  - deploy

build:web:
  stage: web
  image: docker.mydomain.com/gulp
  script:
  - bower install && npm install
  - gulp build
  cache:
    paths: [ bower_components, node_modules ]
  artifacts:
    paths: [ build ]

build:docker:
  stage: dockerize
  services: [ docker.mydomain.com/build/dind ]
  dependencies: [ 'build:web' ]
  script:
  - docker build . -t $DOCKER_TAG
  - docker push $DOCKER_TAG
  - docker inspect --format "{{ index .RepoDigests 0 }}" $DOCKER_TAG > dockersha.txt
  artifacts:
    paths: [dockersha.txt]

ci:
  stage: ci
  dependencies: [ 'build:web', 'build:docker' ]
  script:
  - 'helm upgrade -i myapp-$CI_ENVIRONMENT_SLUG --namespace myapp --set dockerTag=$(cat dockersha.txt) --set version=$CI_ENVIRONMENT_SLUG --set env=$CI_ENVIRONMENT_SLUG --set path=$CI_ENVIRONMENT_SLUG $CHART_DIR' # Deploy the chart templates from the `app` folder
  except: [ master ]
  environment:
    name: staging/$CI_COMMIT_REF_NAME
    url: https://preview.$DOMAIN/$CI_ENVIRONMENT_SLUG/
    on_stop: review_stop

review_stop:
  stage: ci
  when: manual
  except: [ master ]
  variables:
    GIT_STRATEGY: none
  script:
  - helm delete --purge myapp-$CI_ENVIRONMENT_SLUG
  environment:
    name: staging/$CI_COMMIT_REF_NAME
    action: stop

deploy:pilot:
  dependencies: [ 'build:docker' ]
  stage: deploy
  services: [ docker.mydomain.com/build/dind ]
  script:
  - docker pull $(cat dockersha.txt)
  - docker tag $(cat dockersha.txt) docker.mydomain.com/myapp/home
  - docker push docker.mydomain.com/myapp/home
  - helm upgrade -i myappweb --set dockerTag=$(cat dockersha.txt) --set host=pilot --set version=pilot --namespace=myapp $CHART_DIR
  environment:
    name: production
    url: https://www.$DOMAIN/
  only: [master]

deploy:prod:
  dependencies: [ 'build:web' ]
  image: docker.mydomain.com/build/rsync
  stage: deploy
  only: [ master ]
  script:
  - eval $(ssh-agent -s)
  # SSH_PRIVATE_KEY is a secret variable set up in this gitlab repo
  - ssh-add <(echo "$SSH_PRIVATE_KEY" | sed 's/\r//g')
  - mkdir -p $HOME/.ssh
  - echo -e "Host $PROD_RSYNC_HOST\n\tStrictHostKeyChecking no\n\n" > $HOME/.ssh/config
  - rsync -rv --omit-dir-times --delete build/* myusername@$PROD_RSYNC_HOST:/var/www/www.$DOMAIN/

chart-templates-deployment.yaml

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: myapp-{{ .Values.version | default "latest"  | trunc 40 }}
  namespace: {{ .Release.Namespace }}
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: {{ .Values.version | default "latest"  | trunc 40 }}
    spec:
      containers:
      - name: web
        image: {{ .Values.dockerTag | default "latest" }}
        imagePullPolicy: Always
        resources:
          requests:
            cpu: 100m
            memory: 200Mi
        ports:
        - containerPort: 80
        livenessProbe: &g
          httpGet:
            path: /
            port: 80
        readinessProbe: *g
---
apiVersion: v1
kind: Service
metadata:
  name: {{ .Values.version | default "latest"  | trunc 40}}
  namespace: {{ .Release.Namespace }}
spec:
  ports:
  - port: 80
    targetPort: 80
  selector:
    app: {{ .Values.version | default "latest"  | trunc 40 }}
---
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: myapp-version-{{ .Values.version | default "latest" | trunc 40 }}
  namespace: {{ .Release.Namespace }}
  annotations:
    kubernetes.io/tls-vault: "true"
    ingress.kubernetes.io/rewrite-target: "/"
spec:
  rules:
  - host: {{ .Values.host | default "preview" }}.mydomain.com
    http:
      paths:
      # This gives me the ability to mount PR-specific builds at a specific
      # path rather than having proliferating DNS entries/certs.
      - path: /{{ .Values.path | default "" }}
        backend:
          serviceName: {{ .Values.version | default "latest" | trunc 40}}
          servicePort: 80
  tls:
  - secretName: {{ .Values.host | default "preview" }}.mydomain.com.tls
    hosts:
    - {{ .Values.host | default "preview" }}.mydomain.com

Dockerfile

FROM nginx

ADD build/ /usr/share/nginx/html/

not clear how you make

1. helm init --client-only
2. Kubectl i.e ./kube/config already preloaded to docker image ?