From 2db94d3d291a2e8800cdf803e47277e4437c8edb Mon Sep 17 00:00:00 2001
From: halfa <youngyukari@gmail.com>
Date: Mon, 31 Oct 2016 20:20:03 +0900
Subject: [PATCH] Add ping probe

Support packet loss and RTT warning
---
 probe/ping.go | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 probe/ping.go

diff --git a/probe/ping.go b/probe/ping.go
new file mode 100644
index 0000000..d44fd01
--- /dev/null
+++ b/probe/ping.go
@@ -0,0 +1,48 @@
+package probe
+
+import (
+	"time"
+
+	ping "github.com/sparrc/go-ping"
+)
+
+const packetCount = 3
+
+// Ping probe, check network avaibility
+type Ping struct {
+	addr    string
+	warning time.Duration
+	fail    time.Duration
+}
+
+// NewPing returns a ping probe
+func NewPing(addr string, warning, fail time.Duration) *Ping {
+	return &Ping{
+		addr:    addr,
+		warning: warning,
+		fail:    fail,
+	}
+}
+
+// Probe send 3 ICMP packets and wait for replies
+// Warning is issued when a reply is missing or if rtt exeed `warning`
+// Failure occure when target is unreachable
+func (p *Ping) Probe() (status Status, message string) {
+	pinger := &ping.Pinger{
+		Timeout: p.fail,
+		Count:   packetCount,
+	}
+	pinger.SetAddr(p.addr)
+
+	pinger.Run()
+	stats := pinger.Statistics()
+
+	if stats.PacketsRecv == 0 {
+		return StatusError, "Unreacheable"
+	}
+
+	if stats.PacketsRecv < packetCount {
+		return StatusWarning, "Packet loss"
+	}
+	return EvaluateDuration(stats.AvgRtt, p.warning)
+}