extract link.ParseCollection

common/link/link.go

@@ -1,7 +1,9 @@
 package link
 
 import (
+	"encoding/base64"
 	"net/url"
+	"strings"
 
 	"github.com/sagernet/sing-box/option"
 	E "github.com/sagernet/sing/common/exceptions"
@@ -34,3 +36,49 @@ func Parse(u *url.URL) (Link, error) {
 	}
 	return nil, E.Errors(errs...)
 }
+
+// ParseCollection parses a links collection string to []Link
+func ParseCollection(content string) ([]Link, error) {
+	content = doBase64DecodeOrNothing(content)
+	links := make([]Link, 0)
+	errs := make([]error, 0)
+	for _, line := range strings.Split(content, "\n") {
+		line = strings.TrimSpace(line)
+		if line == "" {
+			continue
+		}
+		u, err := url.Parse(line)
+		if err != nil {
+			continue
+		}
+		link, err := Parse(u)
+		if err != nil {
+			errs = append(errs, err)
+			continue
+		}
+		links = append(links, link)
+	}
+	return links, E.Errors(errs...)
+}
+
+func doBase64DecodeOrNothing(s string) string {
+	b, err := base64Decode(s)
+	if err != nil {
+		return s
+	}
+	return string(b)
+}
+
+func base64Decode(b64 string) ([]byte, error) {
+	b64 = strings.TrimSpace(b64)
+	stdb64 := b64
+	if pad := len(b64) % 4; pad != 0 {
+		stdb64 += strings.Repeat("=", 4-pad)
+	}
+
+	b, err := base64.StdEncoding.DecodeString(stdb64)
+	if err != nil {
+		return base64.URLEncoding.DecodeString(b64)
+	}
+	return b, nil
+}

common/link/ss.go

@@ -1,7 +1,6 @@
 package link
 
 import (
-	"encoding/base64"
 	"fmt"
 	"net/url"
 	"strconv"
@@ -87,17 +86,3 @@ func (l *SSLink) Options() *option.Outbound {
 		},
 	}
 }
-
-func base64Decode(b64 string) ([]byte, error) {
-	b64 = strings.TrimSpace(b64)
-	stdb64 := b64
-	if pad := len(b64) % 4; pad != 0 {
-		stdb64 += strings.Repeat("=", 4-pad)
-	}
-
-	b, err := base64.StdEncoding.DecodeString(stdb64)
-	if err != nil {
-		return base64.URLEncoding.DecodeString(b64)
-	}
-	return b, nil
-}

service/subscription.go

@@ -2,12 +2,9 @@ package service
 
 import (
 	"context"
-	"encoding/base64"
 	"io"
 	"net"
 	"net/http"
-	"net/url"
-	"strings"
 	"time"
 
 	"github.com/sagernet/sing-box/adapter"
@@ -144,63 +141,19 @@ func (s *Subscription) fetchProvider(client *http.Client, provider option.Subscr
 	if err != nil {
 		return nil, err
 	}
-	// try undecoded
+	links, err := link.ParseCollection(string(body))
-	content := string(body)
-	links, err := linksFromContent(content)
 	if len(links) > 0 {
 		if err != nil {
-			s.logger.Warn("some links failed", err)
+			s.logger.Warn("links parsed with error:", err)
 		}
 		return links, nil
 	}
-	// try decoded
+	if err != nil {
-	decoded, err := base64Decode(content)
+		return nil, err
-	links, err = linksFromContent(string(decoded))
-	if len(links) > 0 {
-		if err != nil {
-			s.logger.Warn("some links failed", err)
-		}
-		return links, nil
 	}
 	return nil, E.New("no links found")
 }
 
-func linksFromContent(content string) ([]link.Link, error) {
-	links := make([]link.Link, 0)
-	errs := make([]error, 0)
-	for _, line := range strings.Split(content, "\n") {
-		line = strings.TrimSpace(line)
-		if line == "" {
-			continue
-		}
-		u, err := url.Parse(line)
-		if err != nil {
-			continue
-		}
-		link, err := link.Parse(u)
-		if err != nil {
-			errs = append(errs, err)
-			continue
-		}
-		links = append(links, link)
-	}
-	return links, E.Errors(errs...)
-}
-
-func base64Decode(b64 string) ([]byte, error) {
-	b64 = strings.TrimSpace(b64)
-	stdb64 := b64
-	if pad := len(b64) % 4; pad != 0 {
-		stdb64 += strings.Repeat("=", 4-pad)
-	}
-
-	b, err := base64.StdEncoding.DecodeString(stdb64)
-	if err != nil {
-		return base64.URLEncoding.DecodeString(b64)
-	}
-	return b, nil
-}
-
 func (s *Subscription) client() (*http.Client, error) {
 	var detour adapter.Outbound
 	if s.options.DownloadDetour != "" {