From 06b1a7d513c4121fc2d2af7e587c0dacc2f4cc7e Mon Sep 17 00:00:00 2001
From: Dan Mace <ironcladlou@gmail.com>
Date: Wed, 15 Jul 2020 16:03:59 -0400
Subject: [PATCH] WIP: Introduce an etcd operator leader status field

This patch explores adding an etcd operator status field which reports
leader member information. Exposing this would allow, for example, smarter
decision-making by the MCO regarding reboot ordering by providing a hint
to help minimize disruption via excessive leader changes.
---
 operator/v1/0000_20_etcd-operator_01.crd.yaml | 11 +++++++++++
 operator/v1/types_etcd.go                     | 12 ++++++++++++
 operator/v1/zz_generated.deepcopy.go          | 17 +++++++++++++++++
 3 files changed, 40 insertions(+)

diff --git a/operator/v1/0000_20_etcd-operator_01.crd.yaml b/operator/v1/0000_20_etcd-operator_01.crd.yaml
index ad1eadc5fd7..445f7e00229 100644
--- a/operator/v1/0000_20_etcd-operator_01.crd.yaml
+++ b/operator/v1/0000_20_etcd-operator_01.crd.yaml
@@ -149,6 +149,17 @@ spec:
               description: latestAvailableRevisionReason describe the detailed reason
                 for the most recent deployment
               type: string
+            leader:
+              description: leader describes the etcd member which is currently the
+                leader. This field is a hint and shouldn't be considered authoritative.
+              type: object
+              properties:
+                name:
+                  description: name is the etcd leader member name, if available.
+                  type: string
+                node:
+                  description: node is the etcd leader member node, if available.
+                  type: string
             nodeStatuses:
               description: nodeStatuses track the deployment values and errors across
                 individual nodes
diff --git a/operator/v1/types_etcd.go b/operator/v1/types_etcd.go
index 6a2fbdb9acf..6a9685445ac 100644
--- a/operator/v1/types_etcd.go
+++ b/operator/v1/types_etcd.go
@@ -26,6 +26,18 @@ type EtcdSpec struct {
 
 type EtcdStatus struct {
 	StaticPodOperatorStatus `json:",inline"`
+
+	// leader describes the etcd member which is currently the leader. This field
+	// is a hint and shouldn't be considered authoritative.
+	Leader LeaderStatus `json:"leader"`
+}
+
+// leaderStatus describes the etcd leader member details.
+type LeaderStatus struct {
+	// name is the etcd leader member name, if available.
+	Name string `json:"name,omitempty"`
+	// node is the etcd leader member node, if available.
+	Node string `json:"node,omitempty"`
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
diff --git a/operator/v1/zz_generated.deepcopy.go b/operator/v1/zz_generated.deepcopy.go
index 110dae102e7..b02344250c5 100644
--- a/operator/v1/zz_generated.deepcopy.go
+++ b/operator/v1/zz_generated.deepcopy.go
@@ -776,6 +776,7 @@ func (in *EtcdSpec) DeepCopy() *EtcdSpec {
 func (in *EtcdStatus) DeepCopyInto(out *EtcdStatus) {
 	*out = *in
 	in.StaticPodOperatorStatus.DeepCopyInto(&out.StaticPodOperatorStatus)
+	out.Leader = in.Leader
 	return
 }
 
@@ -1476,6 +1477,22 @@ func (in *KuryrConfig) DeepCopy() *KuryrConfig {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *LeaderStatus) DeepCopyInto(out *LeaderStatus) {
+	*out = *in
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new LeaderStatus.
+func (in *LeaderStatus) DeepCopy() *LeaderStatus {
+	if in == nil {
+		return nil
+	}
+	out := new(LeaderStatus)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *LoadBalancerStrategy) DeepCopyInto(out *LoadBalancerStrategy) {
 	*out = *in