From 4acaa5a2a0f3d714bebd406f1dc40c3ea7d19de9 Mon Sep 17 00:00:00 2001
From: tangcong <tangcong506@gmail.com>
Date: Sat, 6 Jun 2020 14:24:41 +0800
Subject: [PATCH 1/3] etcdserver/api/etcdhttp: add reason field for /health
 response

---
 etcdserver/api/etcdhttp/metrics.go | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/etcdserver/api/etcdhttp/metrics.go b/etcdserver/api/etcdhttp/metrics.go
index e6365a8c9..b34a26dfe 100644
--- a/etcdserver/api/etcdhttp/metrics.go
+++ b/etcdserver/api/etcdhttp/metrics.go
@@ -90,6 +90,7 @@ func init() {
 // TODO: remove manual parsing in etcdctl cluster-health
 type Health struct {
 	Health string `json:"health"`
+	Reason string `json:"reason"`
 }
 
 // TODO: server NOSPACE, etcdserver.ErrNoLeader in health API
@@ -109,6 +110,14 @@ func checkHealth(lg *zap.Logger, srv etcdserver.ServerV2) (h Health) {
 	if len(as) > 0 {
 		h.Health = "false"
 		for _, v := range as {
+			switch v.Alarm {
+			case etcdserverpb.AlarmType_NOSPACE:
+				h.Reason = "ALARM NOSPACE"
+			case etcdserverpb.AlarmType_CORRUPT:
+				h.Reason = "ALARM CORRUPT"
+			default:
+				h.Reason = "ALARM UNKNOWN"
+			}
 			lg.Warn("serving /health false due to an alarm", zap.String("alarm", v.String()))
 		}
 		return
@@ -116,6 +125,7 @@ func checkHealth(lg *zap.Logger, srv etcdserver.ServerV2) (h Health) {
 
 	if uint64(srv.Leader()) == raft.None {
 		h.Health = "false"
+		h.Reason = "RAFT NO LEADER"
 		lg.Warn("serving /health false; no leader")
 		return
 	}
@@ -125,6 +135,7 @@ func checkHealth(lg *zap.Logger, srv etcdserver.ServerV2) (h Health) {
 	cancel()
 	if err != nil {
 		h.Health = "false"
+		h.Reason = "QGET ERROR"
 		lg.Warn("serving /health false; QGET fails", zap.Error(err))
 	}
 

From f77b21ce055227c00a5727d1de7eda35fef8f03b Mon Sep 17 00:00:00 2001
From: tangcong <tangcong506@gmail.com>
Date: Sat, 6 Jun 2020 14:35:30 +0800
Subject: [PATCH 2/3] CHANGELOG: update for 11983

---
 CHANGELOG-3.5.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG-3.5.md b/CHANGELOG-3.5.md
index f3062e0da..6fe21c4bd 100644
--- a/CHANGELOG-3.5.md
+++ b/CHANGELOG-3.5.md
@@ -122,6 +122,7 @@ Note that any `etcd_debugging_*` metrics are experimental and subject to change.
   - See https://github.com/etcd-io/etcd/issues/11918.
 - Improve logging around snapshot send and receive.
 - [Push down RangeOptions.limit argv into index tree to reduce memory overhead](https://github.com/etcd-io/etcd/pull/11990).
+- Add [reason field for /health response](https://github.com/etcd-io/etcd/pull/11983).
 
 ### Package `embed`
 

From 330424142c7fb86876004debac396a5d23b01708 Mon Sep 17 00:00:00 2001
From: tangcong <tangcong506@gmail.com>
Date: Sat, 6 Jun 2020 15:35:53 +0800
Subject: [PATCH 3/3] tests/e2e: fix failed /health test case

---
 tests/e2e/ctl_v3_alarm_test.go | 2 +-
 tests/e2e/metrics_test.go      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/e2e/ctl_v3_alarm_test.go b/tests/e2e/ctl_v3_alarm_test.go
index 4d3df2a93..a6ef5e398 100644
--- a/tests/e2e/ctl_v3_alarm_test.go
+++ b/tests/e2e/ctl_v3_alarm_test.go
@@ -53,7 +53,7 @@ func alarmTest(cx ctlCtx) {
 	}
 
 	// '/health' handler should return 'false'
-	if err := cURLGet(cx.epc, cURLReq{endpoint: "/health", expected: `{"health":"false"}`}); err != nil {
+	if err := cURLGet(cx.epc, cURLReq{endpoint: "/health", expected: `{"health":"false","reason":"ALARM NOSPACE"}`}); err != nil {
 		cx.t.Fatalf("failed get with curl (%v)", err)
 	}
 
diff --git a/tests/e2e/metrics_test.go b/tests/e2e/metrics_test.go
index 1ce401d93..e20b0f88d 100644
--- a/tests/e2e/metrics_test.go
+++ b/tests/e2e/metrics_test.go
@@ -49,7 +49,7 @@ func metricsTest(cx ctlCtx) {
 		{"/metrics", fmt.Sprintf("etcd_mvcc_delete_total 3")},
 		{"/metrics", fmt.Sprintf(`etcd_server_version{server_version="%s"} 1`, version.Version)},
 		{"/metrics", fmt.Sprintf(`etcd_cluster_version{cluster_version="%s"} 1`, version.Cluster(version.Version))},
-		{"/health", `{"health":"true"}`},
+		{"/health", `{"health":"true","reason":""}`},
 	} {
 		i++
 		if err := ctlV3Put(cx, fmt.Sprintf("%d", i), "v", ""); err != nil {