From 4ea966aedfc829cd5c8027128d115fe5e48e0b9d Mon Sep 17 00:00:00 2001
From: Cromefire_ <cromefire_@outlook.com>
Date: Sat, 20 Feb 2021 14:28:00 +0100
Subject: [PATCH 1/2] Added more resilient polling

---
 main.go                   | 18 +++++++++---------
 pkg/cloudflare/updater.go | 19 ++++++++++++++++++-
 2 files changed, 27 insertions(+), 10 deletions(-)

diff --git a/main.go b/main.go
index d02e06f..bfaafd9 100644
--- a/main.go
+++ b/main.go
@@ -188,9 +188,9 @@ func startPollServer(out chan<- *net.IP, localIp *net.IP) {
 			if err != nil {
 				log.WithError(err).Warn("Failed to poll WAN IPv4 from router")
 			} else {
+				out <- &ipv4
 				if !lastV4.Equal(ipv4) {
 					log.WithField("ipv4", ipv4).Info("New WAN IPv4 found")
-					out <- &ipv4
 					lastV4 = ipv4
 				}
 
@@ -214,18 +214,18 @@ func startPollServer(out chan<- *net.IP, localIp *net.IP) {
 				if err != nil {
 					log.WithError(err).Warn("Failed to poll IPv6 Prefix from router")
 				} else {
-					if !lastV6.Equal(prefix.IP) {
+					constructedIp := make(net.IP, net.IPv6len)
+					copy(constructedIp, prefix.IP)
 
-						constructedIp := make(net.IP, net.IPv6len)
-						copy(constructedIp, prefix.IP)
+					for i := 0; i < net.IPv6len; i++ {
+						constructedIp[i] = constructedIp[i] + (*localIp)[i]
+					}
 
-						for i := 0; i < net.IPv6len; i++ {
-							constructedIp[i] = constructedIp[i] + (*localIp)[i]
-						}
+					log.WithField("prefix", prefix).WithField("ipv6", constructedIp).Info("New IPv6 Prefix found")
 
-						log.WithField("prefix", prefix).WithField("ipv6", constructedIp).Info("New IPv6 Prefix found")
+					out <- &constructedIp
 
-						out <- &constructedIp
+					if !lastV6.Equal(prefix.IP) {
 						lastV6 = prefix.IP
 					}
 				}
diff --git a/pkg/cloudflare/updater.go b/pkg/cloudflare/updater.go
index f9b5a9c..d9b673b 100644
--- a/pkg/cloudflare/updater.go
+++ b/pkg/cloudflare/updater.go
@@ -25,6 +25,9 @@ type Updater struct {
 	api    *cf.API
 
 	In chan *net.IP
+
+	lastIpv4 *net.IP
+	lastIpv6 *net.IP
 }
 
 func NewUpdater() *Updater {
@@ -129,6 +132,15 @@ func (u *Updater) spawnWorker() {
 	for {
 		select {
 		case ip := <-u.In:
+			if ip.To4() == nil {
+				if u.lastIpv6 != nil && u.lastIpv6.Equal(*ip) {
+					continue
+				}
+			} else {
+				if u.lastIpv4 != nil && u.lastIpv4.Equal(*ip) {
+					continue
+				}
+			}
 			log.WithField("ip", ip).Info("Received update request")
 
 			for _, action := range u.actions {
@@ -192,7 +204,7 @@ func (u *Updater) spawnWorker() {
 					// cloudflare-go might revert them to default values.
 					err := u.api.UpdateDNSRecord(action.CfZoneId, record.ID, cf.DNSRecord{
 						Content: ip.String(),
-						TTL: record.TTL,
+						TTL:     record.TTL,
 						Proxied: record.Proxied,
 					})
 
@@ -203,6 +215,11 @@ func (u *Updater) spawnWorker() {
 				}
 			}
 
+			if ip.To4() == nil {
+				u.lastIpv6 = ip
+			} else {
+				u.lastIpv4 = ip
+			}
 		}
 	}
 }

From 0eaa74fb18e3beebaf42b77f0ebd50282a8c5b42 Mon Sep 17 00:00:00 2001
From: Cromefire_ <cromefire_@outlook.com>
Date: Sat, 20 Feb 2021 14:36:14 +0100
Subject: [PATCH 2/2] Skip redundant cloudflare updates

---
 pkg/cloudflare/updater.go | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pkg/cloudflare/updater.go b/pkg/cloudflare/updater.go
index d9b673b..e305f53 100644
--- a/pkg/cloudflare/updater.go
+++ b/pkg/cloudflare/updater.go
@@ -200,6 +200,10 @@ func (u *Updater) spawnWorker() {
 				for _, record := range records {
 					alog.WithField("record-id", record.ID).Info("Updating DNS record")
 
+					if record.Content == ip.String() {
+						continue
+					}
+
 					// Ensure we submit all required fields even if they did not change,otherwise
 					// cloudflare-go might revert them to default values.
 					err := u.api.UpdateDNSRecord(action.CfZoneId, record.ID, cf.DNSRecord{