From cb59c38964af480676f5ed1af032e3d0d9cee833 Mon Sep 17 00:00:00 2001
From: Gyuho Lee <gyuhox@gmail.com>
Date: Wed, 23 May 2018 14:13:26 -0700
Subject: [PATCH] etcdserver/api/rafthttp: add
 "etcd_network_active_peers/disconnected_peers_total"

Signed-off-by: Gyuho Lee <gyuhox@gmail.com>
---
 etcdserver/api/rafthttp/metrics.go     | 20 ++++++++++++++++++++
 etcdserver/api/rafthttp/peer_status.go |  6 ++++++
 2 files changed, 26 insertions(+)

diff --git a/etcdserver/api/rafthttp/metrics.go b/etcdserver/api/rafthttp/metrics.go
index c63a082f6d5a..327be6232bf2 100644
--- a/etcdserver/api/rafthttp/metrics.go
+++ b/etcdserver/api/rafthttp/metrics.go
@@ -17,6 +17,24 @@ package rafthttp
 import "github.com/prometheus/client_golang/prometheus"
 
 var (
+	activePeers = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+		Namespace: "etcd",
+		Subsystem: "network",
+		Name:      "active_peers",
+		Help:      "The current number of active peer connections.",
+	},
+		[]string{"ID"},
+	)
+
+	disconnectedPeers = prometheus.NewCounterVec(prometheus.CounterOpts{
+		Namespace: "etcd",
+		Subsystem: "network",
+		Name:      "disconnected_peers_total",
+		Help:      "The total number of disconnected peers.",
+	},
+		[]string{"ID"},
+	)
+
 	sentBytes = prometheus.NewCounterVec(prometheus.CounterOpts{
 		Namespace: "etcd",
 		Subsystem: "network",
@@ -68,6 +86,8 @@ var (
 )
 
 func init() {
+	prometheus.MustRegister(activePeers)
+	prometheus.MustRegister(disconnectedPeers)
 	prometheus.MustRegister(sentBytes)
 	prometheus.MustRegister(receivedBytes)
 	prometheus.MustRegister(sentFailures)
diff --git a/etcdserver/api/rafthttp/peer_status.go b/etcdserver/api/rafthttp/peer_status.go
index 68d9ac01b5bb..4374299c6bae 100644
--- a/etcdserver/api/rafthttp/peer_status.go
+++ b/etcdserver/api/rafthttp/peer_status.go
@@ -53,6 +53,8 @@ func (s *peerStatus) activate() {
 		}
 		s.active = true
 		s.since = time.Now()
+
+		activePeers.WithLabelValues(s.id.String()).Inc()
 	}
 }
 
@@ -69,8 +71,12 @@ func (s *peerStatus) deactivate(failure failureType, reason string) {
 		}
 		s.active = false
 		s.since = time.Time{}
+
+		activePeers.WithLabelValues(s.id.String()).Dec()
+		disconnectedPeers.WithLabelValues(s.id.String()).Inc()
 		return
 	}
+
 	if s.lg != nil {
 		s.lg.Debug("peer deactivated again", zap.String("peer-id", s.id.String()), zap.Error(errors.New(msg)))
 	}