feat: Added SubFolder and localAssets configuration(#1324)

Co-authored-by: eaglexmw <eagle_xmw@163.com>

conf/config.go

@@ -28,6 +28,8 @@ type Config struct {
 	Address  string      `json:"address" env:"ADDR"`
 	Port     int         `json:"port" env:"PORT"`
 	Assets   string      `json:"assets" env:"ASSETS"`
+	LocalAssets string   `json:"localassets" env:"LOCALASSETS"`
+	SubFolder string     `json:"subfolder" env:"SUBFOLDER"`
 	Database Database    `json:"database"`
 	Scheme   Scheme      `json:"scheme"`
 	Cache    CacheConfig `json:"cache"`
@@ -39,6 +41,8 @@ func DefaultConfig() *Config {
 		Address: "0.0.0.0",
 		Port:    5244,
 		Assets:  "https://npm.elemecdn.com/alist-web@$version/dist",
+		SubFolder: "",
+		LocalAssets: "",
 		TempDir: "data/temp",
 		Database: Database{
 			Type:        "sqlite3",

server/static.go

@@ -2,11 +2,14 @@ package server
 
 import (
 	"io/fs"
+	"os"
 	"io/ioutil"
 	"net/http"
 	"net/http/pprof"
 	"strings"
+	"path/filepath"
 
+	"github.com/Xhofe/alist/utils"
 	"github.com/Xhofe/alist/conf"
 	"github.com/Xhofe/alist/public"
 	"github.com/gin-gonic/gin"
@@ -19,31 +22,65 @@ func InitIndex() {
 	if !strings.Contains(conf.Conf.Assets, "/") {
 		conf.Conf.Assets = conf.DefaultConfig().Assets
 	}
+	// if LocalAssets is local path, read local index.html.
+	if (utils.IsDir(filepath.Dir(conf.Conf.LocalAssets))) && utils.Exists(filepath.Join(conf.Conf.LocalAssets, "index.html")) {
+		index, err = os.Open(filepath.Join(conf.Conf.LocalAssets, "index.html"))
+		defer index.Close()
+		log.Infof("used local index.html")
+	} else {
 		index, err = public.Public.Open("index.html")
+	}
 	if err != nil {
 		log.Fatal(err.Error())
 	}
     data, _ := ioutil.ReadAll(index)
+	conf.RawIndexHtml = string(data)
+	// if exist SUB_FOLDER, replace it by config: SubFolder
+	subfolder := strings.Trim(conf.Conf.SubFolder, "/")
+	if strings.Contains(conf.RawIndexHtml, "SUB_FOLDER") {
+		conf.RawIndexHtml = strings.ReplaceAll(conf.RawIndexHtml, "SUB_FOLDER", subfolder)
+	}
 	cdnUrl := strings.ReplaceAll(conf.Conf.Assets, "$version", conf.WebTag)
 	cdnUrl = strings.TrimRight(cdnUrl, "/")
-	conf.RawIndexHtml = string(data)
 	if strings.Contains(conf.RawIndexHtml, "CDN_URL") {
+		if (cdnUrl == "") && (subfolder != "") {
+			conf.RawIndexHtml = strings.ReplaceAll(conf.RawIndexHtml, "CDN_URL", subfolder)
+			conf.RawIndexHtml = strings.ReplaceAll(conf.RawIndexHtml, "assets/", "/" + subfolder+"/assets/")	
+		} else {
 			conf.RawIndexHtml = strings.ReplaceAll(conf.RawIndexHtml, "/CDN_URL", cdnUrl)
 			conf.RawIndexHtml = strings.ReplaceAll(conf.RawIndexHtml, "assets/", cdnUrl+"/assets/")	
 		}
+	}
 }
 
 func Static(r *gin.Engine) {
+	var assets fs.FS
+	var pub fs.FS
+	var err error
+	var fsys fs.FS
 	//InitIndex()
-	assets, err := fs.Sub(public.Public, "assets")
+	// if LocalAssets is local path, read local assets.
+	fsys = os.DirFS(conf.Conf.LocalAssets)
+	if (utils.IsDir(filepath.Dir(conf.Conf.LocalAssets))) && utils.Exists(filepath.Join(conf.Conf.LocalAssets, "assets")) {
+		assets, err = fs.Sub(fsys, "assets")
+		log.Infof("used local assets")
+	} else {
+		assets, err = fs.Sub(public.Public, "assets")
+	}
 	if err != nil {
 		log.Fatalf("can't find assets folder")
 	}
-	pub, err := fs.Sub(public.Public, "public")
+	r.StaticFS("/assets/", http.FS(assets))
+    // if LocalAssets is local path, read local assets.
+	if (utils.IsDir(filepath.Dir(conf.Conf.LocalAssets))) && utils.Exists(filepath.Join(conf.Conf.LocalAssets, "public")) {
+		pub, err = fs.Sub(fsys, "public")
+		log.Infof("used local public")
+	} else {
+		pub, err = fs.Sub(public.Public, "public")
+	}
 	if err != nil {
 		log.Fatalf("can't find public folder")
 	}
-	r.StaticFS("/assets/", http.FS(assets))
 	r.StaticFS("/public/", http.FS(pub))
 	r.NoRoute(func(c *gin.Context) {
 		c.Header("Content-Type", "text/html")