Update: Initialize the config file outside of the init function

config/initial.go

@@ -0,0 +1,72 @@
+package config
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"io"
+	"net/http"
+	"os"
+	"strings"
+
+	C "github.com/Dreamacro/clash/constant"
+
+	log "github.com/sirupsen/logrus"
+)
+
+func downloadMMDB(path string) (err error) {
+	resp, err := http.Get("http://geolite.maxmind.com/download/geoip/database/GeoLite2-Country.tar.gz")
+	if err != nil {
+		return
+	}
+	defer resp.Body.Close()
+
+	gr, err := gzip.NewReader(resp.Body)
+	if err != nil {
+		return
+	}
+	defer gr.Close()
+
+	tr := tar.NewReader(gr)
+	for {
+		h, err := tr.Next()
+		if err == io.EOF {
+			break
+		} else if err != nil {
+			return err
+		}
+
+		if !strings.HasSuffix(h.Name, "GeoLite2-Country.mmdb") {
+			continue
+		}
+
+		f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0644)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		_, err = io.Copy(f, tr)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// Init prepare necessary files
+func Init() {
+	// initial config.ini
+	if _, err := os.Stat(C.ConfigPath); os.IsNotExist(err) {
+		log.Info("Can't find config, create a empty file")
+		os.OpenFile(C.ConfigPath, os.O_CREATE|os.O_WRONLY, 0644)
+	}
+
+	// initial mmdb
+	if _, err := os.Stat(C.MMDBPath); os.IsNotExist(err) {
+		log.Info("Can't find MMDB, start download")
+		err := downloadMMDB(C.MMDBPath)
+		if err != nil {
+			log.Fatalf("Can't download MMDB: %s", err.Error())
+		}
+	}
+}

constant/config.go

@@ -1,14 +1,9 @@
 package constant
 
 import (
-	"archive/tar"
-	"compress/gzip"
-	"io"
-	"net/http"
 	"os"
 	"os/user"
 	"path"
-	"strings"
 
 	log "github.com/sirupsen/logrus"
 )
@@ -52,57 +47,5 @@ func init() {
 	}
 
 	ConfigPath = path.Join(dirPath, "config.ini")
-	if _, err := os.Stat(ConfigPath); os.IsNotExist(err) {
-		log.Info("Can't find config, create a empty file")
-		os.OpenFile(ConfigPath, os.O_CREATE|os.O_WRONLY, 0644)
-	}
-
 	MMDBPath = path.Join(dirPath, "Country.mmdb")
-	if _, err := os.Stat(MMDBPath); os.IsNotExist(err) {
-		log.Info("Can't find MMDB, start download")
-		err := downloadMMDB(MMDBPath)
-		if err != nil {
-			log.Fatalf("Can't download MMDB: %s", err.Error())
-		}
-	}
-}
-
-func downloadMMDB(path string) (err error) {
-	resp, err := http.Get("http://geolite.maxmind.com/download/geoip/database/GeoLite2-Country.tar.gz")
-	if err != nil {
-		return
-	}
-	defer resp.Body.Close()
-
-	gr, err := gzip.NewReader(resp.Body)
-	if err != nil {
-		return
-	}
-	defer gr.Close()
-
-	tr := tar.NewReader(gr)
-	for {
-		h, err := tr.Next()
-		if err == io.EOF {
-			break
-		} else if err != nil {
-			return err
-		}
-
-		if !strings.HasSuffix(h.Name, "GeoLite2-Country.mmdb") {
-			continue
-		}
-
-		f, err := os.OpenFile(path, os.O_CREATE|os.O_WRONLY, 0644)
-		if err != nil {
-			return err
-		}
-		defer f.Close()
-		_, err = io.Copy(f, tr)
-		if err != nil {
-			return err
-		}
-	}
-
-	return nil
 }

main.go

@@ -18,6 +18,7 @@ func main() {
 	proxy.Instance().Run()
 	hub.Run()
 
+	config.Init()
 	err := config.Instance().Parse()
 	if err != nil {
 		log.Fatalf("Parse config error: %s", err.Error())