Kubernetes service per pod metacontroller

Question

I was trying to setup Service per Pod in stateful set with metacontroller: https://github.com/metacontroller/metacontroller/tree/master/examples/service-per-pod

I was following linked instruction, I was playing with various combination, but I still didn't achieve what is described. Services are not created together with pod.

In this example, I was trying to put service-per-pod-label: "web" against the name of the pod.

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nginx
  annotations:
    service-per-pod-label: "statefulset.kubernetes.io/pod-name"
    service-per-pod-ports: "80:80"
spec:
  selector:
    matchLabels:
      app: nginx
  serviceName: nginx
  replicas: 3
  template:
    metadata:
      labels:
        app: nginx
    spec:
      terminationGracePeriodSeconds: 1
      containers:
      - name: nginx
        image: gcr.io/google_containers/nginx-slim:0.8
        ports:
        - containerPort: 80
          name: web

my metacontroller is up and running

NAME                                   READY   STATUS    RESTARTS   AGE
metacontroller-metacontroller-helm-0   1/1     Running   0          23m

logs from metacontroller: kubectl logs metacontroller-metacontroller-helm-0

{"level":"info","ts":1660492483.489682,"msg":"Configuration information","discovery-interval":20,"cache-flush-interval":1800,"metrics-address":":9999","client-go-qps":5,"client-go-burst":10,"workers":5,"events-qps":0.0033333333333333335,"events-burst":25,"pprofAddr":"0","leader-election":false,"leader-election-resource-lock":"leases","leader-election-namespace":"","leader-election-id":"metacontroller","version":"4.3.4"}
{"level":"info","ts":1660492483.5292923,"msg":"Communication with K8s API server successful"}
{"level":"info","ts":1660492484.7299764,"msg":"Waited for 1.19273971s due to client-side throttling, not priority and fairness, request: GET:https://10.3.0.1:443/apis/authorization.k8s.io/v1?timeout=32s\n"}
{"level":"info","ts":1660492489.1358352,"logger":"controller-runtime.metrics","msg":"Metrics server is starting to listen","addr":":9999"}
{"level":"info","ts":1660492489.1373081,"msg":"Starting EventSource","controller":"composite-metacontroller","source":"kind source: *v1alpha1.CompositeController"}
{"level":"info","ts":1660492489.1373482,"msg":"Starting Controller","controller":"composite-metacontroller"}
{"level":"info","ts":1660492489.1376293,"msg":"Starting EventSource","controller":"decorator-metacontroller","source":"kind source: *v1alpha1.DecoratorController"}
{"level":"info","ts":1660492489.1376536,"msg":"Starting Controller","controller":"decorator-metacontroller"}
{"level":"info","ts":1660492489.1371636,"msg":"Starting server","path":"/metrics","kind":"metrics","addr":"[::]:9999"}
{"level":"info","ts":1660492489.2376945,"msg":"Starting workers","controller":"composite-metacontroller","worker count":1}
{"level":"info","ts":1660492489.2379737,"msg":"Starting workers","controller":"decorator-metacontroller","worker count":1}
{"level":"info","ts":1660492494.7370083,"msg":"Waited for 5.587625994s due to client-side throttling, not priority and fairness, request: GET:https://10.3.0.1:443/apis/networking.k8s.io/v1?timeout=32s\n"}
{"level":"info","ts":1660492510.3382494,"msg":"Waited for 1.165526209s due to client-side throttling, not priority and fairness, request: GET:https://10.3.0.1:443/apis/flowcontrol.apiserver.k8s.io/v1beta2?timeout=32s\n"}

Answer 1

As explained in the documentation, for Kubernetes 1.9+, your service-per-pod-label should have "statefulset.kubernetes.io/pod-name" as value:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nginx
  annotations:
    service-per-pod-label: "statefulset.kubernetes.io/pod-name"
    service-per-pod-ports: "80:80"
spec:
  selector:
    matchLabels:
      app: nginx
  serviceName: nginx
  replicas: 3
  template:
    metadata:
      labels:
        app: nginx
    spec:
      terminationGracePeriodSeconds: 1
      containers:
      - name: nginx
        image: gcr.io/google_containers/nginx-slim:0.8
        ports:
        - containerPort: 80
          name: web

And for earlier versions, you should add the annotation pod-name-label: "pod-name" for your pod`:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: nginx
  annotations:
    service-per-pod-label: "pod-name"
    service-per-pod-ports: "80:80"
spec:
  selector:
    matchLabels:
      app: nginx
  serviceName: nginx
  replicas: 3
  template:
    metadata:
      labels:
        app: nginx
      annotations:
        pod-name-label: "pod-name"
    spec:
      terminationGracePeriodSeconds: 1
      containers:
      - name: nginx
        image: gcr.io/google_containers/nginx-slim:0.8
        ports:
        - containerPort: 80
          name: web

In the two cases, you should use the term pod-name, and not another value. They use it to know the name they should use for the created services.