etcd-operator should add status to etcdclusters/<clustername> when lost quorum

[nvtkaszpir]

Right now etcd-operator is not updating status of etcdclusters/ in case of loosing quorum.

Steps to reproduce:

1. create etcd-operator deployment

   kubectl apply -f etcd-operator.deployment.yaml

# etcd-operator.deployment.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  name: etcd-operator
spec:
  replicas: 1
  template:
    metadata:
      labels:
        name: etcd-operator
    spec:
      containers:
      - name: etcd-operator
        image: quay.io/coreos/etcd-operator:v0.9.4
        command:
        - etcd-operator
        env:
        - name: MY_POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        - name: MY_POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name

2. create etcd crd from 3 nodes:

   kubectl apply -f etcd-cluster.crd.yaml

# etcd-cluster.crd.yaml
apiVersion: "etcd.database.coreos.com/v1beta2"
kind: "EtcdCluster"
metadata:
  name: "etcd"
spec:
  size: 3
  version: "3.2.13"

3. wait till cluster is set up

   kubectl get etcdclusters/etcd -o yaml

   apiVersion: etcd.database.coreos.com/v1beta2
   kind: EtcdCluster
   metadata:
   annotations:
   kubectl.kubernetes.io/last-applied-configuration: |
     {"apiVersion":"etcd.database.coreos.com/v1beta2","kind":"EtcdCluster","metadata":{"annotations":{},"labels":{"etcd-operator-managed":"true"},"name":"etcd","namespace":"default"},"spec":{"size":3,"version":"3.2.13"}}
   creationTimestamp: "2019-03-13T23:37:49Z"
   generation: 1
   labels:
   etcd-operator-managed: "true"
   name: etcd
   namespace: default
   resourceVersion: "2182831"
   selfLink: /apis/etcd.database.coreos.com/v1beta2/namespaces/default/etcdclusters/etcd
   uid: 037a6ceb-45e9-11e9-8b71-42010a8a000a
   spec:
   repository: quay.io/coreos/etcd
   size: 3
   version: 3.2.13
   status:
   clientPort: 2379
   conditions:
   - lastTransitionTime: "2019-03-13T23:38:30Z"
   lastUpdateTime: "2019-03-13T23:38:30Z"
   reason: Cluster available
   status: "True"
   type: Available
   currentVersion: 3.2.13
   members:
   ready:
   - etcd-6r6rpjsmtk
   - etcd-r5fdrln4sh
   - etcd-xkdcxc95vg
   phase: Running
   serviceName: etcd-client
   size: 3
   targetVersion: ""

   kubectl get pods
   NAME                             READY   STATUS    RESTARTS   AGE
   etcd-6r6rpjsmtk                  1/1     Running   0          43s
   etcd-operator-5c6bddb7f6-lxwqb   1/1     Running   0          93s
   etcd-r5fdrln4sh                  1/1     Running   0          27s
   etcd-xkdcxc95vg                  1/1     Running   0          51s

4. kill 2 pods out of 3:

   kubectl delete pod/etcd-6r6rpjsmtk pod/etcd-r5fdrln4sh
   pod "etcd-6r6rpjsmtk" deleted
   pod "etcd-r5fdrln4sh" deleted

5. see etcd-operator log it reports that it lost quorum

   stern etcd-operator
   ...
   etcd-operator-5c6bddb7f6-lxwqb etcd-operator time="2019-03-13T23:41:58Z" level=info msg="cluster membership: etcd-6r6rpjsmtk,etcd-r5fdrln4sh,etcd-xkdcxc95vg" cluster-name=etcd cluster-namespace=default pkg=cluster
   etcd-operator-5c6bddb7f6-lxwqb etcd-operator time="2019-03-13T23:41:58Z" level=info msg="Finish reconciling" cluster-name=etcd cluster-namespace=default pkg=cluster
   etcd-operator-5c6bddb7f6-lxwqb etcd-operator time="2019-03-13T23:41:58Z" level=error msg="failed to reconcile: lost quorum" cluster-name=etcd cluster-namespace=default pkg=cluster

6. check etcdclusters/etcd

   kubectl get etcdclusters/etcd -o yaml

apiVersion: etcd.database.coreos.com/v1beta2
kind: EtcdCluster
metadata:
  annotations:
    kubectl.kubernetes.io/last-applied-configuration: |
      {"apiVersion":"etcd.database.coreos.com/v1beta2","kind":"EtcdCluster","metadata":{"annotations":{},"labels":{"etcd-operator-managed":"true"},"name":"etcd","namespace":"default"},"spec":{"size":3,"version":"3.2.13"}}
  creationTimestamp: "2019-03-13T23:37:49Z"
  generation: 1
  labels:
    etcd-operator-managed: "true"
  name: etcd
  namespace: default
  resourceVersion: "2182831"
  selfLink: /apis/etcd.database.coreos.com/v1beta2/namespaces/default/etcdclusters/etcd
  uid: 037a6ceb-45e9-11e9-8b71-42010a8a000a
spec:
  repository: quay.io/coreos/etcd
  size: 3
  version: 3.2.13
status:
  clientPort: 2379
  conditions:
  - lastTransitionTime: "2019-03-13T23:38:30Z"
    lastUpdateTime: "2019-03-13T23:38:30Z"
    reason: Cluster available
    status: "True"
    type: Available
  currentVersion: 3.2.13
  members:
    ready:
    - etcd-6r6rpjsmtk
    - etcd-r5fdrln4sh
    - etcd-xkdcxc95vg
  phase: Running
  serviceName: etcd-client
  size: 3
  targetVersion: ""

inspect status section.

I believe there should be an info that cluster is in bad state.

[nvtkaszpir]

this is a duplicate of #1973 but with much better description ;)