Merge pull request #11 from mkelcik/upgrade

Upgrade packages + go

.github/workflows/quality-checks.yml

@@ -22,7 +22,7 @@ jobs:
     steps:
       - uses: actions/setup-go@v4
         with:
-          go-version: '1.20'
+          go-version: '1.21'
           cache: false
       - uses: actions/checkout@v3
       - name: golangci-lint
@@ -39,7 +39,7 @@ jobs:
       - name: Prepare go environment
         uses: actions/setup-go@v4
         with:
-          go-version: '1.20'
+          go-version: '1.21.5'
           cache: false
       - name: Install dep scanner
         run: |
@@ -58,7 +58,7 @@ jobs:
       - name: Prepare go environment
         uses: actions/setup-go@v4
         with:
-          go-version: '1.20'
+          go-version: '1.21'
           cache: false
       - name: Run tests
         run: go test --cover -coverprofile coverage.out -covermode count -v ./...

Dockerfile

@@ -1,10 +1,10 @@
-FROM golang:1.20 as build
+FROM golang:1.21 as build
 
 # Copy project sources
 COPY . /opt/project/
 WORKDIR /opt/project
 
-RUN apt-get update && apt-get install -y --no-install-recommends ca-certificates=20210119
+RUN apt-get update && apt-get install -y --no-install-recommends ca-certificates=20230311
 
 RUN CGO_ENABLED=0 go build -ldflags="-s -w" -o /cloudflare-ddns-updater
 

Makefile

@@ -0,0 +1,2 @@
+test:
+	go test --cover -covermode count -v ./...

README.md

@@ -1,9 +1,11 @@
+![Code and security checks](https://github.com/mkelcik/cloudflare-ddns-update/actions/workflows/quality-checks.yml/badge.svg)
+
 ## What is Cloudflare Dynamic DNS?
 DNS records are static, and it does not play well with dynamic IP addresses. Now, to solve that problem, you’ll need to set up dynamic DNS. Cloudflare provides an API that allows you to manage DNS records programmatically.
 
 To set up a Cloudflare dynamic DNS, you’ll need to run a process on a client inside your network that does two main actions: get your network’s current public IP address and automatically update the corresponding DNS record.
 
-This simple updater do the job.
+This simple updater do the job, and send notifications, if change happen.
 
 ## How to run
 ### Environment variables
@@ -15,7 +17,25 @@ Before run, you need configure this environment variables.
  - `CLOUDFLARE_ZONE` - (required) zone name with domain you want to check. See: [https://developers.cloudflare.com/fundamentals/get-started/concepts/accounts-and-zones/#zones](https://developers.cloudflare.com/fundamentals/get-started/concepts/accounts-and-zones/#zones)
  - `ON_CHANGE_COMMENT` - (optional) in the event that the ip address of the dns record changes, this comment will be added to the record
  - `CHECK_INTERVAL_SECONDS` - (optional) how often will the ip address of the records be checked (default: `300`)
- - `PUBLIC_IP_RESOLVER` - (optional) public ip address resolver. For now only resolving via `https://ifconfig.me` is implemented. (default: `ifconfig.me`)
+ - `PUBLIC_IP_RESOLVER` - (optional) public ip address resolver. (default: `ifconfig.me`) Available: `ifconfig.me`, `v4.ident.me`, `1.1.1.1`
+ - `NOTIFIERS` - (optional) setting the notifier in case of an update of the dns record. Multiple entries are separated by commas. (default none). Example: `webhook@http://localhost/cloudflare-notification`
+
+### Notifications
+
+Currently, only webhook notification is available. Webhook sends a POST request to the specified endpoint in json format.
+
+Request body example:
+```json
+{
+  "old_ip": "xxx.xxx.xxx.xxx",
+  "new_ip": "xxx.xxx.xxx.xxx",
+  "checked_at": "2023-05-04T17:39:42.942850354+02:00",
+  "resolver_tag": "ifconfig.me",
+  "domain": "my.domain.com"
+}
+```
+
+Other notification methods will be implemented later (check future plans section).
 
 ### Building from source
 
@@ -43,9 +63,11 @@ version: "3"
 services:
   cf-dns-updater:
     image: mkelcik/cloudflare-ddns-update:latest
+    restart: unless-stopped
     environment:
       - CLOUDFLARE_DNS_TO_CHECK=my.testdomain.com,your.testdomain.com
       - CLOUDFLARE_API_KEY=your_cloudflare_api_key
+      - NOTIFIERS=webhook@http://localhost/cloudflare-updated-notification
       - CLOUDFLARE_ZONE=testdomain.com
       - ON_CHANGE_COMMENT="automatically updated"
       - CHECK_INTERVAL_SECONDS=300
@@ -56,6 +78,12 @@ services:
 docker run -e CLOUDFLARE_DNS_TO_CHECK=my.testdomain.com,your.testdomain.com -e CLOUDFLARE_API_KEY=your_cloudflare_api_key -e CLOUDFLARE_ZONE=testdomain.com -e ON_CHANGE_COMMENT="automatically updated" -e CHECK_INTERVAL_SECONDS=300 mkelcik/cloudflare-ddns-update:latest 
 ```
 
+### Future plans
+
+ - prometheus metrics
+ - mqtt and rabbitmq notifiers
+ - IPv6 support
+
 ### Contributing 
 
-Feel free to contribute and pls report bugs. Thanks
+Feel free to contribute and pls report bugs. Thanks

docker-compose.yaml

@@ -2,6 +2,7 @@ version: "3"
 services:
   cf-dns-updater:
     image: mkelcik/cloudflare-ddns-update:latest
+    restart: unless-stopped
     environment:
       - CLOUDFLARE_DNS_TO_CHECK=my.testdomain.com,your.testdomain.com
       - CLOUDFLARE_API_KEY=your_cloudflare_api_key

go.mod

@@ -1,14 +1,15 @@
 module github.com/mkelcik/cloudflare-ddns-update
 
-go 1.20
+go 1.21
 
-require github.com/cloudflare/cloudflare-go v0.66.0
+require github.com/cloudflare/cloudflare-go v0.83.0
 
 require (
+	github.com/goccy/go-json v0.10.2 // indirect
 	github.com/google/go-querystring v1.1.0 // indirect
 	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
-	github.com/hashicorp/go-retryablehttp v0.7.2 // indirect
-	golang.org/x/net v0.9.0 // indirect
-	golang.org/x/text v0.9.0 // indirect
-	golang.org/x/time v0.3.0 // indirect
+	github.com/hashicorp/go-retryablehttp v0.7.5 // indirect
+	golang.org/x/net v0.19.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
+	golang.org/x/time v0.5.0 // indirect
 )

go.sum

@@ -1,8 +1,12 @@
 github.com/cloudflare/cloudflare-go v0.66.0 h1:B74IvVGQ4UFYJnqQSK/9GbR+Y1HwNxqqdN2Bmg0dckg=
 github.com/cloudflare/cloudflare-go v0.66.0/go.mod h1:tA44hjU9FfycofKT+lWWMHb/dEq1pRbiVPGuJo1WzLQ=
+github.com/cloudflare/cloudflare-go v0.83.0 h1:aq85Hbr5W6KfXZV7v3lx6fhBkiu0FYqY+3+xzG14mdY=
+github.com/cloudflare/cloudflare-go v0.83.0/go.mod h1:5pkAzpoWJYI5NekLZoRryQAcghYDhdbUxdcal1f7lu4=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fatih/color v1.13.0 h1:8LOYc1KYPPmyKMuN8QV2DNRWNbLo6LZ0iLs8+mlH53w=
+github.com/goccy/go-json v0.10.2 h1:CrxCmQqYDkv1z7lO7Wbh2HN93uovUHgrECaO5ZrCXAU=
+github.com/goccy/go-json v0.10.2/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MGFi0w8I=
 github.com/google/go-cmp v0.5.2/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.8 h1:e6P7q2lk1O+qJJb4BtCQXlK8vWEO8V1ZeuEdJNOqZyg=
 github.com/google/go-querystring v1.1.0 h1:AnCroh3fv4ZBgVIf1Iwtovgjaw/GiKJo8M8yD/fhyJ8=
@@ -13,6 +17,8 @@ github.com/hashicorp/go-hclog v0.9.2/go.mod h1:5CU+agLiy3J7N7QjHK5d05KxGsuXiQLrj
 github.com/hashicorp/go-hclog v1.2.0 h1:La19f8d7WIlm4ogzNHB0JGqs5AUDAZ2UfCY4sJXcJdM=
 github.com/hashicorp/go-retryablehttp v0.7.2 h1:AcYqCvkpalPnPF2pn0KamgwamS42TqUDDYFRKq/RAd0=
 github.com/hashicorp/go-retryablehttp v0.7.2/go.mod h1:Jy/gPYAdjqffZ/yFGCFV2doI5wjtH1ewM9u8iYVjtX8=
+github.com/hashicorp/go-retryablehttp v0.7.5 h1:bJj+Pj19UZMIweq/iie+1u5YCdGrnxCT9yvm0e+Nd5M=
+github.com/hashicorp/go-retryablehttp v0.7.5/go.mod h1:Jy/gPYAdjqffZ/yFGCFV2doI5wjtH1ewM9u8iYVjtX8=
 github.com/mattn/go-colorable v0.1.12 h1:jF+Du6AlPIjs2BiUiQlKOX0rt3SujHxPnksPKZbaA40=
 github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -21,10 +27,17 @@ github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXf
 github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
 golang.org/x/net v0.9.0 h1:aWJ/m6xSmxWBx+V0XRHTlrYrPG56jKsLdTFmsSsCzOM=
 golang.org/x/net v0.9.0/go.mod h1:d48xBJpPfHeWQsugry2m+kC02ZBRGRgulfHnEXEuWns=
+golang.org/x/net v0.19.0 h1:zTwKpTd2XuCqf8huc7Fo2iSy+4RHPd10s4KzeTnVr1c=
+golang.org/x/net v0.19.0/go.mod h1:CfAk/cbD4CthTvqiEl8NpboMuiuOYsAr/7NOjZJtv1U=
 golang.org/x/sys v0.7.0 h1:3jlCCIQZPdOYu1h8BkNvLz8Kgwtae2cagcG/VamtZRU=
+golang.org/x/sys v0.15.0 h1:h48lPFYpsTvQJZF4EKyI4aLHaev3CxivZmv7yZig9pc=
 golang.org/x/text v0.9.0 h1:2sjJmO8cDvYveuX97RDLsxlyUxLl+GHoLxBiRdHllBE=
 golang.org/x/text v0.9.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
+golang.org/x/text v0.14.0 h1:ScX5w1eTa3QqT8oi6+ziP7dTV1S2+ALU0bI+0zXKWiQ=
+golang.org/x/text v0.14.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
 golang.org/x/time v0.3.0 h1:rg5rLMjNzMS1RkNLzCG38eapWhnYLFYXDXj2gOlr8j4=
 golang.org/x/time v0.3.0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
+golang.org/x/time v0.5.0 h1:o7cqy6amK/52YcAKIPlM3a+Fpj35zvRj2TP+e1xFSfk=
+golang.org/x/time v0.5.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

internal/config.go

@@ -17,6 +17,7 @@ const (
 	envKeyCloudflareZone       = "CLOUDFLARE_ZONE"
 	envKeyOnChangeComment      = "ON_CHANGE_COMMENT"
 	envKeyCheckIntervalSeconds = "CHECK_INTERVAL_SECONDS"
+	envKeyNotifiers            = "NOTIFIERS"
 )
 
 type Config struct {
@@ -25,6 +26,7 @@ type Config struct {
 	ApiToken            string
 	CloudflareZone      string
 	OnChangeComment     string
+	Notifiers           []string
 	CheckInterval       time.Duration
 }
 
@@ -52,11 +54,12 @@ func NewConfig() Config {
 	}
 
 	return Config{
-		DnsRecordsToCheck:   parseDNSToCheck(os.Getenv(envKeyDnsToCheck)),
+		DnsRecordsToCheck:   parseCommaDelimited(os.Getenv(envKeyDnsToCheck)),
 		PublicIpResolverTag: os.Getenv(envKeyPublicIpResolverTag),
 		ApiToken:            os.Getenv(envKeyCloudflareApiKey),
 		CloudflareZone:      os.Getenv(envKeyCloudflareZone),
 		OnChangeComment:     os.Getenv(envKeyOnChangeComment),
+		Notifiers:           parseCommaDelimited(os.Getenv(envKeyNotifiers)),
 		CheckInterval:       time.Duration(checkInterval) * time.Second,
 	}
 }

internal/helpers.go

@@ -2,10 +2,10 @@ package internal
 
 import "strings"
 
-func parseDNSToCheck(data string) []string {
+func parseCommaDelimited(data string) []string {
 	out := make([]string, 0, strings.Count(data, ",")+1)
-	for _, dns := range strings.Split(data, ",") {
-		if w := strings.TrimSpace(dns); w != "" {
+	for _, item := range strings.Split(data, ",") {
+		if w := strings.TrimSpace(item); w != "" {
 			out = append(out, w)
 		}
 	}

internal/helpers_test.go

@@ -38,8 +38,8 @@ func Test_parseDNSToCheck(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			if got := parseDNSToCheck(tt.args.data); !reflect.DeepEqual(got, tt.want) {
-				t.Errorf("parseDNSToCheck() = %v, want %v", got, tt.want)
+			if got := parseCommaDelimited(tt.args.data); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("parseCommaDelimited() = %v, want %v", got, tt.want)
 			}
 		})
 	}

main.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/cloudflare/cloudflare-go"
 	"github.com/mkelcik/cloudflare-ddns-update/internal"
+	"github.com/mkelcik/cloudflare-ddns-update/notifications"
 	"github.com/mkelcik/cloudflare-ddns-update/public_resolvers"
 )
 
@@ -17,13 +18,17 @@ type PublicIpResolver interface {
 	ResolvePublicIp(ctx context.Context) (net.IP, error)
 }
 
-func getResolver(resolverName string) PublicIpResolver {
+func getResolver(resolverName string) (PublicIpResolver, string) {
 	switch resolverName {
 	// HERE add another resolver if needed
+	case public_resolvers.CloudflareTraceTag:
+		return public_resolvers.NewDefaultCloudflareTrace(), public_resolvers.CloudflareTraceTag
+	case public_resolvers.V4IdentMeTag:
+		return public_resolvers.NewV4IdentMeDefault(), public_resolvers.V4IdentMeTag
 	case public_resolvers.IfConfigMeTag:
 		fallthrough
 	default:
-		return public_resolvers.NewDefaultIfConfigMe()
+		return public_resolvers.NewDefaultIfConfigMe(), public_resolvers.IfConfigMeTag
 	}
 }
 
@@ -47,51 +52,70 @@ func main() {
 		log.Fatal(err)
 	}
 
-	log.Println("waiting for update tick ...")
+	notifiers := notifications.GetNotifiers(config.Notifiers)
+
+	// public ip resolver
+	publicIpResolver, resolverTag := getResolver(config.PublicIpResolverTag)
+
+	checkFunc := func() {
+		currentPublicIP, err := publicIpResolver.ResolvePublicIp(ctx)
+		if err != nil {
+			log.Fatal(err)
+		}
+		log.Printf("Current public ip `%s` (resolver: %s)", currentPublicIP, resolverTag)
+
+		dns, err := allDNSRecords(ctx, api, cloudflare.ZoneIdentifier(zoneID))
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		for _, dnsRecord := range dns {
+			if internal.Contains(config.DnsRecordsToCheck, dnsRecord.Name) {
+				log.Printf("Checking record `%s` with current value `%s` ...", dnsRecord.Name, dnsRecord.Content)
+				if currentPublicIP.String() == dnsRecord.Content {
+					log.Println("OK")
+					continue // no update needed
+				}
+
+				update := cloudflare.UpdateDNSRecordParams{
+					ID:      dnsRecord.ID,
+					Content: currentPublicIP.String(),
+				}
+
+				if config.OnChangeComment != "" {
+					update.Comment = &config.OnChangeComment
+				}
+
+				if _, err := api.UpdateDNSRecord(ctx, cloudflare.ZoneIdentifier(zoneID), update); err != nil {
+					log.Printf("error updating dns record: %s", err)
+					continue
+				}
+
+				if err := notifiers.NotifyWithLog(ctx, notifications.Notification{
+					OldIp:       net.ParseIP(dnsRecord.Content),
+					NewIp:       currentPublicIP,
+					CheckedAt:   time.Now(),
+					ResolverTag: resolverTag,
+					Domain:      dnsRecord.Name,
+				}); err != nil {
+					log.Printf("errors in notifications: %s", err)
+				}
+				log.Printf("Updated to `%s`", currentPublicIP)
+			}
+		}
+	}
+
+	log.Printf("checking ...")
+	checkFunc()
+
+	log.Println("waiting for check tick ...")
 	ticker := time.NewTicker(config.CheckInterval)
 	defer ticker.Stop()
 	for {
 		select {
 		case <-ticker.C:
 			log.Println("tick received checking ...")
-			func() {
-				currentPublicIP, err := getResolver(config.PublicIpResolverTag).ResolvePublicIp(ctx)
-				if err != nil {
-					log.Fatal(err)
-				}
-
-				log.Printf("Current public ip `%s`", currentPublicIP)
-
-				dns, err := allDNSRecords(ctx, api, cloudflare.ZoneIdentifier(zoneID))
-				if err != nil {
-					log.Fatal(err)
-				}
-
-				for _, dnsRecord := range dns {
-					if internal.Contains(config.DnsRecordsToCheck, dnsRecord.Name) {
-						log.Printf("Checking record `%s` with current value `%s` ...", dnsRecord.Name, dnsRecord.Content)
-						if currentPublicIP.String() == dnsRecord.Content {
-							log.Println("OK")
-							continue // no update needed
-						}
-
-						update := cloudflare.UpdateDNSRecordParams{
-							ID:      dnsRecord.ID,
-							Content: currentPublicIP.String(),
-						}
-
-						if config.OnChangeComment != "" {
-							update.Comment = config.OnChangeComment
-						}
-
-						if _, err := api.UpdateDNSRecord(ctx, cloudflare.ZoneIdentifier(zoneID), update); err != nil {
-							log.Printf("error updating dns record: %s", err)
-						} else {
-							log.Printf("Updated to `%s`", currentPublicIP)
-						}
-					}
-				}
-			}()
+			checkFunc()
 		case <-ctx.Done():
 			break
 		}

notifications/types.go

@@ -0,0 +1,76 @@
+package notifications
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"net"
+	"net/http"
+	"strings"
+	"time"
+)
+
+const (
+	configDelimiter = "@"
+)
+
+type Notifiers []Notifier
+
+func (n Notifiers) NotifyWithLog(ctx context.Context, notification Notification) error {
+	var outErr error
+	for _, notifier := range n {
+		if err := notifier.Notify(ctx, notification); err != nil {
+			outErr = errors.Join(outErr, err)
+			continue
+		}
+		log.Printf("Notification sent via %s\n", notifier.Tag())
+	}
+	return outErr
+}
+
+type Notification struct {
+	OldIp       net.IP    `json:"old_ip,omitempty"`
+	NewIp       net.IP    `json:"new_ip"`
+	CheckedAt   time.Time `json:"checked_at"`
+	ResolverTag string    `json:"resolver_tag"`
+	Domain      string    `json:"domain"`
+}
+
+func (n Notification) ToSlice() []string {
+	return []string{n.OldIp.String(), n.NewIp.String(), n.CheckedAt.Format(time.RFC3339), n.ResolverTag, n.Domain}
+}
+
+var Available = map[string]func(string) (Notifier, error){
+	webhookTag: func(config string) (Notifier, error) {
+		parts := strings.Split(config, configDelimiter)
+
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("wrong webhook config, missing url part")
+		}
+
+		return NewWebhookNotification(WebhookConfig{Url: parts[1]}, &http.Client{
+			Timeout: 10 * time.Second,
+		}), nil
+	},
+}
+
+type Notifier interface {
+	Tag() string
+	Notify(ctx context.Context, notification Notification) error
+}
+
+func GetNotifiers(tags []string) Notifiers {
+	out := Notifiers{}
+	for _, t := range tags {
+		if initFn, ok := Available[strings.Split(t, configDelimiter)[0]]; ok {
+			notifier, err := initFn(t)
+			if err != nil {
+				log.Println(err)
+				continue
+			}
+			out = append(out, notifier)
+		}
+	}
+	return out
+}

notifications/webhook.go

@@ -0,0 +1,66 @@
+package notifications
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+)
+
+const (
+	webhookTag = "webhook"
+)
+
+type Doer interface {
+	Do(*http.Request) (*http.Response, error)
+}
+
+type WebhookConfig struct {
+	Url string
+}
+
+type WebhookNotification struct {
+	config WebhookConfig
+	client Doer
+}
+
+func (w WebhookNotification) Tag() string {
+	return webhookTag
+}
+
+func NewWebhookNotification(config WebhookConfig, client Doer) *WebhookNotification {
+	return &WebhookNotification{config: config, client: client}
+}
+
+func (w WebhookNotification) getRequestBody(notification Notification) (io.Reader, error) {
+	out := bytes.NewBuffer(nil)
+	if err := json.NewEncoder(out).Encode(notification); err != nil {
+		return nil, fmt.Errorf("error encoding json notification body: %w", err)
+	}
+	return out, nil
+}
+
+func (w WebhookNotification) Notify(ctx context.Context, notification Notification) error {
+	body, err := w.getRequestBody(notification)
+	if err != nil {
+		return fmt.Errorf("WebhookNotification::NotifyWithLog error: %w", err)
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, w.config.Url, body)
+	if err != nil {
+		return fmt.Errorf("WebhookNotification::NotifyWithLog error creating request: %w", err)
+	}
+
+	resp, err := w.client.Do(req)
+	if err != nil {
+		return fmt.Errorf("WebhookNotification::NotifyWithLog error while sending notification: %w", err)
+	}
+	_ = resp.Body.Close()
+
+	if resp.StatusCode >= 300 {
+		return fmt.Errorf("WebhookNotification::NotifyWithLog unexpected non 2xx code %d returned", resp.StatusCode)
+	}
+	return nil
+}

public_resolvers/base_resolver.go

@@ -0,0 +1,55 @@
+package public_resolvers
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+)
+
+var NoIPInResponseError = errors.New("no ip found in response")
+
+type Doer interface {
+	Do(*http.Request) (*http.Response, error)
+}
+
+type ipParserFunc func(reader io.Reader) (string, error)
+
+func defaultIpParser(reader io.Reader) (string, error) {
+	out, err := io.ReadAll(reader)
+	return string(out), err
+}
+
+type baseResolver struct {
+	client   Doer
+	url      string
+	ipParser ipParserFunc
+}
+
+func (i baseResolver) ResolvePublicIp(ctx context.Context) (net.IP, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, i.url, nil)
+	if err != nil {
+		return net.IP{}, fmt.Errorf("error creating ifconfig request: %w", err)
+	}
+
+	resp, err := i.client.Do(req)
+	if err != nil {
+		return net.IP{}, err
+	}
+	defer func() {
+		_ = resp.Body.Close()
+	}()
+
+	if resp.StatusCode != http.StatusOK {
+		return net.IP{}, fmt.Errorf("unexpected response code %d", resp.StatusCode)
+	}
+
+	ipText, err := i.ipParser(resp.Body)
+	if err != nil {
+		return net.IP{}, fmt.Errorf("error reading body: %w", err)
+	}
+
+	return net.ParseIP(ipText), nil
+}

public_resolvers/base_resolver_test.go

@@ -0,0 +1,100 @@
+package public_resolvers
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"net"
+	"net/http"
+	"reflect"
+	"testing"
+)
+
+// RoundTripFunc .
+type RoundTripFunc func(req *http.Request) *http.Response
+
+// RoundTrip .
+func (f RoundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
+	return f(req), nil
+}
+
+// NewTestClient returns *http.Client with Transport replaced to avoid making real calls
+func NewTestClient(fn RoundTripFunc) *http.Client {
+	return &http.Client{
+		Transport: fn,
+	}
+}
+
+func Test_baseResolver_ResolvePublicIp(t *testing.T) {
+
+	testUrl := "http://my-test-url.url"
+	testIp := `192.168.0.100`
+
+	client := NewTestClient(func(req *http.Request) *http.Response {
+
+		if req.URL.String() != testUrl {
+			return &http.Response{
+				StatusCode: 500,
+				// Send response to be tested
+				Body: io.NopCloser(bytes.NewBufferString(`invalid url`)),
+				// Must be set to non-nil value or it panics
+				Header: make(http.Header),
+			}
+		}
+
+		return &http.Response{
+			StatusCode: 200,
+			// Send response to be tested
+			Body: io.NopCloser(bytes.NewBufferString(testIp)),
+			// Must be set to non-nil value or it panics
+			Header: make(http.Header),
+		}
+	})
+
+	type fields struct {
+		client Doer
+		url    string
+		fn     ipParserFunc
+	}
+	type args struct {
+		ctx context.Context
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		args    args
+		want    net.IP
+		wantErr bool
+	}{
+		{
+			name: "check parse ip4",
+			fields: fields{
+				client: client,
+				url:    testUrl,
+				fn:     defaultIpParser,
+			},
+			args: args{
+				ctx: context.Background(),
+			},
+			want:    net.ParseIP(testIp),
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			i := baseResolver{
+				client:   tt.fields.client,
+				url:      tt.fields.url,
+				ipParser: tt.fields.fn,
+			}
+			got, err := i.ResolvePublicIp(tt.args.ctx)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("ResolvePublicIp() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("ResolvePublicIp() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

public_resolvers/cloudflare_trace.go

@@ -0,0 +1,49 @@
+package public_resolvers
+
+import (
+	"io"
+	"net/http"
+	"strings"
+	"time"
+)
+
+const (
+	CloudflareTraceTag = "1.1.1.1"
+	CloudflareTraceUrl = "https://1.1.1.1/cdn-cgi/trace"
+
+	ipPrefix = "ip="
+)
+
+type CloudflareTrace struct {
+	baseResolver
+}
+
+func NewDefaultCloudflareTrace() *CloudflareTrace {
+	return NewCloudflareTrace(&http.Client{
+		Timeout: 10 * time.Second,
+	})
+}
+
+func cloudflareTraceResponseParser(reader io.Reader) (string, error) {
+	data, err := io.ReadAll(reader)
+	if err != nil {
+		return "", err
+	}
+
+	for _, row := range strings.Split(string(data), "\n") {
+		if strings.Index(row, ipPrefix) == 0 {
+			return strings.TrimSpace(strings.ReplaceAll(row, ipPrefix, "")), nil
+		}
+	}
+	return "", NoIPInResponseError
+}
+
+func NewCloudflareTrace(client Doer) *CloudflareTrace {
+	return &CloudflareTrace{
+		baseResolver: baseResolver{
+			client:   client,
+			url:      CloudflareTraceUrl,
+			ipParser: cloudflareTraceResponseParser,
+		},
+	}
+}

public_resolvers/cloudflare_trace_test.go

@@ -0,0 +1,78 @@
+package public_resolvers
+
+import (
+	"bytes"
+	"io"
+	"testing"
+)
+
+func Test_cloudflareTraceResponseParser(t *testing.T) {
+
+	type args struct {
+		reader io.Reader
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    string
+		wantErr bool
+	}{
+		{
+			name: "ok",
+			args: args{
+				reader: bytes.NewBuffer([]byte(`fl=31f118
+h=1.1.1.1
+ip=94.113.142.206
+ts=1683145336.383
+visit_scheme=https
+uag=Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36
+colo=PRG
+sliver=none
+http=http/2
+loc=CZ
+tls=TLSv1.3
+sni=off
+warp=off
+gateway=off
+rbi=off
+kex=X25519`)),
+			},
+			want:    "94.113.142.206",
+			wantErr: false,
+		},
+		{
+			name: "no ip in response",
+			args: args{
+				reader: bytes.NewBuffer([]byte(`fl=31f118
+h=1.1.1.1
+ts=1683145336.383
+visit_scheme=https
+uag=Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/112.0.0.0 Safari/537.36
+colo=PRG
+sliver=none
+http=http/2
+loc=CZ
+tls=TLSv1.3
+sni=off
+warp=off
+gateway=off
+rbi=off
+kex=X25519`)),
+			},
+			want:    "",
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := cloudflareTraceResponseParser(tt.args.reader)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("cloudflareTraceResponseParser() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if got != tt.want {
+				t.Errorf("cloudflareTraceResponseParser() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

public_resolvers/ifconfigme.go

@@ -1,28 +1,17 @@
 package public_resolvers
 
 import (
-	"context"
-	"fmt"
-	"io"
-	"net"
 	"net/http"
 	"time"
 )
 
 const (
 	IfConfigMeTag = "ifconfig.me"
-)
-
-type Doer interface {
-	Do(*http.Request) (*http.Response, error)
-}
-
-var (
 	ifConfigMeUrl = "https://ifconfig.me"
 )
 
 type IfConfigMe struct {
-	client Doer
+	baseResolver
 }
 
 func NewDefaultIfConfigMe() *IfConfigMe {
@@ -31,32 +20,12 @@ func NewDefaultIfConfigMe() *IfConfigMe {
 	})
 }
 
-func NewIfConfigMe(c Doer) *IfConfigMe {
-	return &IfConfigMe{client: c}
-}
-
-func (i IfConfigMe) ResolvePublicIp(ctx context.Context) (net.IP, error) {
-	req, err := http.NewRequestWithContext(ctx, http.MethodGet, ifConfigMeUrl, nil)
-	if err != nil {
-		return net.IP{}, fmt.Errorf("error creating ifconfig request: %w", err)
-	}
-
-	resp, err := i.client.Do(req)
-	if err != nil {
-		return net.IP{}, err
-	}
-	defer func() {
-		_ = resp.Body.Close()
-	}()
-
-	if resp.StatusCode != http.StatusOK {
-		return net.IP{}, fmt.Errorf("unexpected response code %d", resp.StatusCode)
-	}
-
-	ipText, err := io.ReadAll(resp.Body)
-	if err != nil {
-		return net.IP{}, fmt.Errorf("error reading body: %w", err)
-	}
-
-	return net.ParseIP(string(ipText)), nil
+func NewIfConfigMe(client Doer) *IfConfigMe {
+	return &IfConfigMe{
+		baseResolver: baseResolver{
+			client:   client,
+			url:      ifConfigMeUrl,
+			ipParser: defaultIpParser,
+		},
+	}
 }

public_resolvers/v4identme.go

@@ -0,0 +1,31 @@
+package public_resolvers
+
+import (
+	"net/http"
+	"time"
+)
+
+const (
+	V4IdentMeTag = "v4.ident.me"
+	v4IdentMeUrl = "https://v4.ident.me/"
+)
+
+type V4IdentMe struct {
+	baseResolver
+}
+
+func NewV4IdentMeDefault() *V4IdentMe {
+	return NewV4IdentMe(&http.Client{
+		Timeout: 10 * time.Second,
+	})
+}
+
+func NewV4IdentMe(client Doer) *V4IdentMe {
+	return &V4IdentMe{
+		baseResolver: baseResolver{
+			client:   client,
+			url:      v4IdentMeUrl,
+			ipParser: defaultIpParser,
+		},
+	}
+}