add flexibility for redis service

[kongdewen]

we are currently experience an issue that requires us to expose redis service through nodeport. update the redis service template so it can accept NodePort as service type

test 1:
default service value

  service:
    # service type, default: ClusterIP
    type: "ClusterIP"
    # if service type is ClusterIP, a clusterIP can be specified
    clusterIP:
    # if service type is NodePort, a nodePort can be specified
    nodePort:

service template rendering to the original one

apiVersion: v1
kind: Service
metadata:
  name: airflow-redis
  labels:
    tier: airflow
    component: redis
    release: airflow
    chart: "airflow-1.14.0"
    heritage: Helm
spec:
  type: ClusterIP
  selector:
    tier: airflow
    component: redis
    release: airflow
  ports:
    - name: redis-db
      protocol: TCP
      port: 6379
      targetPort: 6379

test 2:
setup clusterIP:

  service:
    # service type, default: ClusterIP
    type: "ClusterIP"
    # if service type is ClusterIP, a clusterIP can be specified
    clusterIP: 127.0.0.1
    # if service type is NodePort, a nodePort can be specified
    nodePort:

apiVersion: v1
kind: Service
metadata:
  name: airflow-redis
  labels:
    tier: airflow
    component: redis
    release: airflow
    chart: "airflow-1.14.0"
    heritage: Helm
spec:
  type: ClusterIP
  clusterIP: 127.0.0.1
  selector:
    tier: airflow
    component: redis
    release: airflow
  ports:
    - name: redis-db
      protocol: TCP
      port: 6379
      targetPort: 6379

test 3:
setup NodePort

  service:
    # service type, default: ClusterIP
    type: "ClusterIP"
    # if service type is ClusterIP, a clusterIP can be specified
    clusterIP:
    # if service type is NodePort, a nodePort can be specified
    nodePort: 11111

apiVersion: v1
kind: Service
metadata:
  name: airflow-redis
  labels:
    tier: airflow
    component: redis
    release: airflow
    chart: "airflow-1.14.0"
    heritage: Helm
spec:
  type: NodePort
  selector:
    tier: airflow
    component: redis
    release: airflow
  ports:
    - name: redis-db
      protocol: TCP
      port: 6379
      targetPort: 6379
      nodePort: 11111

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