Rails Kubernetes Manifests

configmap.yaml

apiVersion: v1
kind: ConfigMap
metadata:
  name: example
  namespace: default
data:
  APPLICATION_HOST: example.com
  LANG: en_US.UTF-8
  PIDFILE: /tmp/server.pid
  PORT: "3000"
  RACK_ENV: production
  RAILS_ENV: production
  RAILS_LOG_TO_STDOUT: "true"
  RAILS_SERVE_STATIC_FILES: "true"

db-migrate.yaml

apiVersion: batch/v1
kind: Job
metadata:
  generateName: db-migrate-
  labels:
    app.kubernetes.io/name: example
  namespace: default
spec:
  template:
    metadata:
      labels:
        app.kubernetes.io/name: example
    spec:
      containers:
      - command:
        - rails
        - db:migrate
        envFrom:
        - configMapRef:
            name: env
        - secretRef:
            name: env
        image: docker.io/mycompany/myapplication:abcd123
        imagePullPolicy: IfNotPresent
        name: main
      restartPolicy: Never

deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app.kubernetes.io/name: example
    process: web
  name: example-web
  namespace: default
spec:
  selector:
    matchLabels:
      app.kubernetes.io/name: example
      process: web
  template:
    metadata:
      labels:
        app.kubernetes.io/name: example
        process: web
    spec:
      containers:
      - env:
        - name: PORT
          value: "3000"
        envFrom:
        - configMapRef:
            name: example
        - secretRef:
            name: example
        image: docker.io/mycompany/myapplication:abcd123
        imagePullPolicy: IfNotPresent
        name: main
        ports:
        - containerPort: 3000
          name: http
          protocol: TCP
        readinessProbe:
          httpGet:
            httpHeaders:
            - name: Host
              value: example.com
            path: /robots.txt
            port: 3000
          initialDelaySeconds: 10
          periodSeconds: 10
          timeoutSeconds: 2
      initContainers:
      - command:
        - rake
        - db:abort_if_pending_migrations
        envFrom:
        - configMapRef:
            name: example
        - secretRef:
            name: example
        image: docker.io/mycompany/myapplication:abcd123
        imagePullPolicy: IfNotPresent
        name: migrations

ingress.yaml

apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
  labels:
    app.kubernetes.io/name: example
  name: example
  namespace: default
spec:
  rules:
  - host: example.com
    http:
      paths:
      - backend:
          serviceName: example-web
          servicePort: 3000
  tls:
  - hosts:
    - example.com
    secretName: example-tls

service.yaml

apiVersion: v1
kind: Service
metadata:
  labels:
    app.kubernetes.io/name: example
    process: web
  name: example-web
  namespace: default
spec:
  ports:
  - name: http
    port: 3000
    protocol: TCP
    targetPort: http
  selector:
    app.kubernetes.io/name: example
    process: web
  type: ClusterIP