if there is no service defined k8s assumes that endpoint is orphaned and removes it.
Patroni tries to create the service only in case if use_endpoints is enabled if the following cases:
1. Upon start
2. When it tries to (re-)create the config endpoint
If for some reason creation of the service has failed, Patroni will retry it on every cycle of HA loop. Usually it fails due to lack of permissions and if you don't want to give such permissions to the service account used by Patroni, you can create the service explicitly in the deployment manifest.
- Update postgres docker image to the latest 11 version.
- Remove empty lines inside the `RUN` command to make the Dockerfile compatible with future docker versions.
- Set the `PATRONI_KUBERNETES_POD_IP` environment variable, which is required when _use_endpoints_ is enabled. Otherwise, the `KeyError` is raised [here](https://github.com/zalando/patroni/blob/master/patroni/dcs/kubernetes.py#L95).
- Set `EDITOR` environment variable to make configuration changes via `patronictl edit-config`.
- It modifies the Dockerfile and entrypoint slightly to allow for OpenShift SCCs to operate correctly
- It adds 2 template examples that can be easily modified by changing parameters
Fixes#572
'patronictl remove' deletes the cluster configuration (stored either in configmaps or endpoints) and cannot be run from the postgres pod w/o 'delete' on those objects being granted to the pod service account.
Adds 3 resources that will properly setup the RBAC:
1. service account, which is also assigned to the pods of the cluster, so that they use those particular permissions
2. a role, which holds only the necessary permissions that patroni members need to interact with k8s cluster
3. a rolebinding, which connects two two former things together to use.
The role and rolebinding was created using this tool https://github.com/liggitt/audit2rbac which looks at [audit logs](https://kubernetes.io/docs/tasks/debug-application-cluster/audit/#advanced-audit) provided by the api server.
* Use ConfigMaps or Endpoins for leader elections and to keep cluster state
* Label pods with a postgres role
* change behavior of pip install. From now on it will not install all dependencies, you have to specify explicitly DCS you want to use Patroni with: `pip install patroni[etcd,zookeeper,kubernetes]`
