Add 1.1.1.1 resolver

Makefile

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

README.md

@@ -17,7 +17,7 @@ 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. (default: `ifconfig.me`) Available: `ifconfig.me`, `v4.ident.me`
+ - `PUBLIC_IP_RESOLVER` - (optional) public ip address resolver. (default: `ifconfig.me`) Available: `ifconfig.me`, `v4.ident.me`, `1.1.1.1`
 
 ### Building from source
 

main.go

@@ -20,6 +20,8 @@ type PublicIpResolver interface {
 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:
@@ -57,7 +59,7 @@ func main() {
 		if err != nil {
 			log.Fatal(err)
 		}
-		log.Printf("Current public ip `%s` (%s)", currentPublicIP, resolverTag)
+		log.Printf("Current public ip `%s` (resolver: %s)", currentPublicIP, resolverTag)
 
 		dns, err := allDNSRecords(ctx, api, cloudflare.ZoneIdentifier(zoneID))
 		if err != nil {

public_resolvers/base_resolver.go

@@ -2,19 +2,30 @@ 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
+	client   Doer
+	url      string
+	ipParser ipParserFunc
 }
 
 func (i baseResolver) ResolvePublicIp(ctx context.Context) (net.IP, error) {
@@ -35,10 +46,10 @@ func (i baseResolver) ResolvePublicIp(ctx context.Context) (net.IP, error) {
 		return net.IP{}, fmt.Errorf("unexpected response code %d", resp.StatusCode)
 	}
 
-	ipText, err := io.ReadAll(resp.Body)
+	ipText, err := i.ipParser(resp.Body)
 	if err != nil {
 		return net.IP{}, fmt.Errorf("error reading body: %w", err)
 	}
 
-	return net.ParseIP(string(ipText)), nil
+	return net.ParseIP(ipText), nil
 }

public_resolvers/base_resolver_test.go

@@ -21,7 +21,7 @@ func (f RoundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
 // NewTestClient returns *http.Client with Transport replaced to avoid making real calls
 func NewTestClient(fn RoundTripFunc) *http.Client {
 	return &http.Client{
-		Transport: RoundTripFunc(fn),
+		Transport: fn,
 	}
 }
 
@@ -54,6 +54,7 @@ func Test_baseResolver_ResolvePublicIp(t *testing.T) {
 	type fields struct {
 		client Doer
 		url    string
+		fn     ipParserFunc
 	}
 	type args struct {
 		ctx context.Context
@@ -70,6 +71,7 @@ func Test_baseResolver_ResolvePublicIp(t *testing.T) {
 			fields: fields{
 				client: client,
 				url:    testUrl,
+				fn:     defaultIpParser,
 			},
 			args: args{
 				ctx: context.Background(),
@@ -81,8 +83,9 @@ func Test_baseResolver_ResolvePublicIp(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			i := baseResolver{
-				client: tt.fields.client,
-				url:    tt.fields.url,
+				client:   tt.fields.client,
+				url:      tt.fields.url,
+				ipParser: tt.fields.fn,
 			}
 			got, err := i.ResolvePublicIp(tt.args.ctx)
 			if (err != nil) != tt.wantErr {

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

@@ -23,8 +23,9 @@ func NewDefaultIfConfigMe() *IfConfigMe {
 func NewIfConfigMe(client Doer) *IfConfigMe {
 	return &IfConfigMe{
 		baseResolver: baseResolver{
-			client: client,
-			url:    ifConfigMeUrl,
+			client:   client,
+			url:      ifConfigMeUrl,
+			ipParser: defaultIpParser,
 		},
 	}
 }

public_resolvers/v4identme.go

@@ -23,8 +23,9 @@ func NewV4IdentMeDefault() *V4IdentMe {
 func NewV4IdentMe(client Doer) *V4IdentMe {
 	return &V4IdentMe{
 		baseResolver: baseResolver{
-			client: client,
-			url:    v4IdentMeUrl,
+			client:   client,
+			url:      v4IdentMeUrl,
+			ipParser: defaultIpParser,
 		},
 	}
 }