[cni-metrics-helper] Expose container port when enabling prometheus metrics

[toVersus]

What type of PR is this?

improvement

Which issue does this PR fix?:

To scrape Prometheus metrics using the Prometheus Operator's PodMonitor, container ports must be exposed via PodSpec:

the port must be specified with container port property.

apiVersion: monitoring.coreos.com/v1
kind: PodMonitor
metadata:
  name: cni-metrics-helper
  namespace: kube-system
spec:
  podMetricsEndpoints:
    - interval: 60s
      port: metrics # or 61681
      scrapeTimeout: 10s
  selector:
    matchLabels:
      k8s-app: cni-metrics-helper

What does this PR do / Why do we need it?:

If we set env.USE_PROMETHEUS to true, the metrics port is defined in the container's port within PodSpec. The port number of cni-metrics-helper cannot be modified, so we can hardcode the port number in Helm chart.

Testing done on this change:

Setting env.USE_PROMETHEUS to true:

helm template cni-metrics-helper . --set-string env.USE_PROMETHEUS="true"

---
# Source: cni-metrics-helper/templates/serviceaccount.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: cni-metrics-helper
  namespace: default
  labels:
    helm.sh/chart: cni-metrics-helper-1.18.0
    app.kubernetes.io/name: cni-metrics-helper
    app.kubernetes.io/instance: cni-metrics-helper
    app.kubernetes.io/version: "v1.18.0"
    app.kubernetes.io/managed-by: Helm
---
# Source: cni-metrics-helper/templates/clusterrole.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: cni-metrics-helper
rules:
  - apiGroups: [""]
    resources:
      - pods
      - pods/proxy
    verbs: ["get", "watch", "list"]
---
# Source: cni-metrics-helper/templates/clusterrolebinding.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: cni-metrics-helper
  labels:
    helm.sh/chart: cni-metrics-helper-1.18.0
    app.kubernetes.io/name: cni-metrics-helper
    app.kubernetes.io/instance: cni-metrics-helper
    app.kubernetes.io/version: "v1.18.0"
    app.kubernetes.io/managed-by: Helm
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cni-metrics-helper
subjects:
  - kind: ServiceAccount
    name: cni-metrics-helper
    namespace: default
---
# Source: cni-metrics-helper/templates/deployment.yaml
kind: Deployment
apiVersion: apps/v1
metadata:
  name: cni-metrics-helper
  namespace: default
  labels:
    k8s-app: cni-metrics-helper
spec:
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: cni-metrics-helper
  template:
    metadata:
      labels:
        k8s-app: cni-metrics-helper
    spec:
      containers:
      - env:
        - name: AWS_CLUSTER_ID
          value: ""
        - name: AWS_VPC_K8S_CNI_LOGLEVEL
          value: "INFO"
        - name: USE_CLOUDWATCH
          value: "true"
        - name: USE_PROMETHEUS
          value: "true"
        name: cni-metrics-helper
        image: "602401143452.dkr.ecr.us-west-2.amazonaws.com/cni-metrics-helper:v1.18.0"
        ports:
        - containerPort: 61681
          name: metrics
      serviceAccountName: cni-metrics-helper

Setting env.USE_PROMETHEUS to false:

helm template cni-metrics-helper . --set-string env.USE_PROMETHEUS="false"

---
# Source: cni-metrics-helper/templates/serviceaccount.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
  name: cni-metrics-helper
  namespace: default
  labels:
    helm.sh/chart: cni-metrics-helper-1.18.0
    app.kubernetes.io/name: cni-metrics-helper
    app.kubernetes.io/instance: cni-metrics-helper
    app.kubernetes.io/version: "v1.18.0"
    app.kubernetes.io/managed-by: Helm
---
# Source: cni-metrics-helper/templates/clusterrole.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
  name: cni-metrics-helper
rules:
  - apiGroups: [""]
    resources:
      - pods
      - pods/proxy
    verbs: ["get", "watch", "list"]
---
# Source: cni-metrics-helper/templates/clusterrolebinding.yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
  name: cni-metrics-helper
  labels:
    helm.sh/chart: cni-metrics-helper-1.18.0
    app.kubernetes.io/name: cni-metrics-helper
    app.kubernetes.io/instance: cni-metrics-helper
    app.kubernetes.io/version: "v1.18.0"
    app.kubernetes.io/managed-by: Helm
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  name: cni-metrics-helper
subjects:
  - kind: ServiceAccount
    name: cni-metrics-helper
    namespace: default
---
# Source: cni-metrics-helper/templates/deployment.yaml
kind: Deployment
apiVersion: apps/v1
metadata:
  name: cni-metrics-helper
  namespace: default
  labels:
    k8s-app: cni-metrics-helper
spec:
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      k8s-app: cni-metrics-helper
  template:
    metadata:
      labels:
        k8s-app: cni-metrics-helper
    spec:
      containers:
      - env:
        - name: AWS_CLUSTER_ID
          value: ""
        - name: AWS_VPC_K8S_CNI_LOGLEVEL
          value: "INFO"
        - name: USE_CLOUDWATCH
          value: "true"
        - name: USE_PROMETHEUS
          value: "false"
        name: cni-metrics-helper
        image: "602401143452.dkr.ecr.us-west-2.amazonaws.com/cni-metrics-helper:v1.18.0"
      serviceAccountName: cni-metrics-helper

Will this PR introduce any new dependencies?:

No

Will this break upgrades or downgrades? Has updating a running cluster been tested?:

No

Does this change require updates to the CNI daemonset config files to work?:

No

Does this PR introduce any user-facing change?:

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[orsenthil]

This change LGTM.
I understand this is useful for certain prometheus operator like PodMonitor.

[orsenthil]

Looks like docker is having an outage right now, building the image is failing for that reason.