feat(static): fetch index.html from cdn for beta (#372)

* refactor(static): simplify folder iteration in Static function

* feat(static): disable local static when `cdn` is set

* feat(static): fetch index.html from cdn for beta

* refactor(static): use RestyClient for better retrying

* fix(static): add Accept header when fetching index.html from CDN

* refactor(static): optimize HTML replacement

* chore(static): add logging to static file system initialization

* feat(static): ensure static file redirected to CDN

server/static/static.go

@@ -9,6 +9,7 @@ import (
 	"os"
 	"strings"
 
+	"github.com/OpenListTeam/OpenList/v4/drivers/base"
 	"github.com/OpenListTeam/OpenList/v4/internal/conf"
 	"github.com/OpenListTeam/OpenList/v4/internal/setting"
 	"github.com/OpenListTeam/OpenList/v4/pkg/utils"
@@ -19,18 +20,45 @@ import (
 var static fs.FS
 
 func initStatic() {
+	utils.Log.Debug("Initializing static file system...")
 	if conf.Conf.DistDir == "" {
 		dist, err := fs.Sub(public.Public, "dist")
 		if err != nil {
-			utils.Log.Fatalf("failed to read dist dir")
+			utils.Log.Fatalf("failed to read dist dir: %v", err)
 		}
 		static = dist
+		utils.Log.Debug("Using embedded dist directory")
 		return
 	}
 	static = os.DirFS(conf.Conf.DistDir)
+	utils.Log.Infof("Using custom dist directory: %s", conf.Conf.DistDir)
+}
+
+func replaceStrings(content string, replacements map[string]string) string {
+	for old, new := range replacements {
+		content = strings.Replace(content, old, new, 1)
+	}
+	return content
 }
 
 func initIndex() {
+	utils.Log.Debug("Initializing index.html...")
+	siteConfig := getSiteConfig()
+	if conf.Conf.DistDir != "" || (conf.Conf.Cdn != "" && (conf.WebVersion == "" || conf.WebVersion == "beta" || conf.WebVersion == "dev")) {
+		utils.Log.Infof("Fetching index.html from CDN: %s/index.html...", conf.Conf.Cdn)
+		resp, err := base.RestyClient.R().
+			SetHeader("Accept", "text/html").
+			Get(fmt.Sprintf("%s/index.html", siteConfig.Cdn))
+		if err != nil {
+			utils.Log.Fatalf("failed to fetch index.html from CDN: %v", err)
+		}
+		if resp.StatusCode() != http.StatusOK {
+			utils.Log.Fatalf("failed to fetch index.html from CDN, status code: %d", resp.StatusCode())
+		}
+		conf.RawIndexHtml = string(resp.Body())
+		utils.Log.Info("Successfully fetched index.html from CDN")
+	} else {
+		utils.Log.Debug("Reading index.html from static files system...")
 		indexFile, err := static.Open("index.html")
 		if err != nil {
 			if errors.Is(err, fs.ErrNotExist) {
@@ -46,61 +74,73 @@ func initIndex() {
 			utils.Log.Fatalf("failed to read dist/index.html")
 		}
 		conf.RawIndexHtml = string(index)
-	siteConfig := getSiteConfig()
+		utils.Log.Debug("Successfully read index.html from static files system")
+	}
+	utils.Log.Debug("Replacing placeholders in index.html...")
 	replaceMap := map[string]string{
 		"cdn: undefined":       fmt.Sprintf("cdn: '%s'", siteConfig.Cdn),
 		"base_path: undefined": fmt.Sprintf("base_path: '%s'", siteConfig.BasePath),
 	}
-	for k, v := range replaceMap {
+	conf.RawIndexHtml = replaceStrings(conf.RawIndexHtml, replaceMap)
-		conf.RawIndexHtml = strings.Replace(conf.RawIndexHtml, k, v, 1)
-	}
 	UpdateIndex()
 }
 
 func UpdateIndex() {
+	utils.Log.Debug("Updating index.html with settings...")
 	favicon := setting.GetStr(conf.Favicon)
 	title := setting.GetStr(conf.SiteTitle)
 	customizeHead := setting.GetStr(conf.CustomizeHead)
 	customizeBody := setting.GetStr(conf.CustomizeBody)
 	mainColor := setting.GetStr(conf.MainColor)
-	conf.ManageHtml = conf.RawIndexHtml
+	utils.Log.Debug("Applying replacements for default pages...")
 	replaceMap1 := map[string]string{
 		"https://cdn.oplist.org/gh/OpenListTeam/Logo@main/logo.svg": favicon,
 		"Loading...":            title,
 		"main_color: undefined": fmt.Sprintf("main_color: '%s'", mainColor),
 	}
-	for k, v := range replaceMap1 {
+	conf.ManageHtml = replaceStrings(conf.RawIndexHtml, replaceMap1)
-		conf.ManageHtml = strings.Replace(conf.ManageHtml, k, v, 1)
+	utils.Log.Debug("Applying replacements for manage pages...")
-	}
-	conf.IndexHtml = conf.ManageHtml
 	replaceMap2 := map[string]string{
 		"<!-- customize head -->": customizeHead,
 		"<!-- customize body -->": customizeBody,
 	}
-	for k, v := range replaceMap2 {
+	conf.IndexHtml = replaceStrings(conf.ManageHtml, replaceMap2)
-		conf.IndexHtml = strings.Replace(conf.IndexHtml, k, v, 1)
+	utils.Log.Debug("Index.html update completed")
-	}
 }
 
 func Static(r *gin.RouterGroup, noRoute func(handlers ...gin.HandlerFunc)) {
+	utils.Log.Debug("Setting up static routes...")
 	initStatic()
 	initIndex()
 	folders := []string{"assets", "images", "streamer", "static"}
+	if conf.Conf.Cdn == "" {
+		utils.Log.Debug("Setting up static file serving...")
 		r.Use(func(c *gin.Context) {
-		for i := range folders {
+			for _, folder := range folders {
-			if strings.HasPrefix(c.Request.RequestURI, fmt.Sprintf("/%s/", folders[i])) {
+				if strings.HasPrefix(c.Request.RequestURI, fmt.Sprintf("/%s/", folder)) {
 					c.Header("Cache-Control", "public, max-age=15552000")
 				}
 			}
 		})
-	for i, folder := range folders {
+		for _, folder := range folders {
 			sub, err := fs.Sub(static, folder)
 			if err != nil {
 				utils.Log.Fatalf("can't find folder: %s", folder)
 			}
-		r.StaticFS(fmt.Sprintf("/%s/", folders[i]), http.FS(sub))
+			utils.Log.Debugf("Setting up route for folder: %s", folder)
+			r.StaticFS(fmt.Sprintf("/%s/", folder), http.FS(sub))
+		}
+	} else {
+		// Ensure static file redirected to CDN
+		for _, folder := range folders {
+			r.GET(fmt.Sprintf("/%s/*filepath", folder), func(c *gin.Context) {
+				filepath := c.Param("filepath")
+				c.Redirect(http.StatusFound, fmt.Sprintf("%s/%s%s", conf.Conf.Cdn, folder, filepath))
+			})
+		}
 	}
 
+	utils.Log.Debug("Setting up catch-all route...")
 	noRoute(func(c *gin.Context) {
 		if c.Request.Method != "GET" && c.Request.Method != "POST" {
 			c.Status(405)