perf: cache generated image thumbnails

2026-09-22 05:51:06 +08:00
parent f799104fb2
commit e6806de5f6
4 changed files with 225 additions and 27 deletions
@@ -37,25 +37,27 @@ import (
 var webIndex []byte

 type Server struct {
-	Store          storage.Storage
-	Auth           *auth.Manager
-	Sessions       map[string]*auth.Account
-	SessionExpiry  map[string]time.Time
-	SessionMu      sync.RWMutex
-	SessionTimeout int
-	JWTSecret      string
-	WebDAVRoot     string
-	WebDAVFS       webdav.FileSystem
-	Allow          string
-	MultiRoot      bool
-	RemoveMode     int
-	ImagePreview   bool
-	FolderDownload string
-	HTMLTitle      string
-	HTMLNotice     string
-	Log            *opslog.Logger
-	UserStore      *auth.UserStore
-	UserHome       string
+	Store              storage.Storage
+	Auth               *auth.Manager
+	Sessions           map[string]*auth.Account
+	SessionExpiry      map[string]time.Time
+	SessionMu          sync.RWMutex
+	SessionTimeout     int
+	JWTSecret          string
+	WebDAVRoot         string
+	WebDAVFS           webdav.FileSystem
+	Allow              string
+	MultiRoot          bool
+	RemoveMode         int
+	ImagePreview       bool
+	FolderDownload     string
+	HTMLTitle          string
+	HTMLNotice         string
+	Log                *opslog.Logger
+	UserStore          *auth.UserStore
+	UserHome           string
+	ThumbnailCache     *thumbnailCache
+	thumbnailCacheOnce sync.Once
 }
 type fileInfo struct {
 	Name      string `json:"name"`
@@ -1176,20 +1178,36 @@ func (s *Server) thumbnail(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer f.Close()
-	src, _, err := image.Decode(f)
+	fi, err := f.Stat()
+	if err != nil {
+		http.NotFound(w, r)
+		return
+	}
+	key := thumbnailCacheKey{Path: file, Size: fi.Size(), ModTime: fi.ModTime().UnixNano()}
+	s.thumbnailCacheOnce.Do(func() {
+		if s.ThumbnailCache == nil {
+			s.ThumbnailCache = newThumbnailCache()
+		}
+	})
+	data, err := s.ThumbnailCache.Do(key, func() ([]byte, error) {
+		src, _, err := image.Decode(f)
+		if err != nil {
+			return nil, err
+		}
+		thumb := transform.Resize(src, 320, 240, transform.Linear)
+		var buf bytes.Buffer
+		if err := png.Encode(&buf, thumb); err != nil {
+			return nil, err
+		}
+		return append([]byte(nil), buf.Bytes()...), nil
+	})
 	if err != nil {
 		http.Error(w, "thumbnail unavailable", http.StatusUnsupportedMediaType)
 		return
 	}
-	thumb := transform.Resize(src, 320, 240, transform.Linear)
-	var buf bytes.Buffer
-	if err := png.Encode(&buf, thumb); err != nil {
-		http.Error(w, "thumbnail unavailable", http.StatusInternalServerError)
-		return
-	}
 	w.Header().Set("Content-Type", "image/png")
 	w.Header().Set("Cache-Control", "private, max-age=300")
-	_, _ = w.Write(buf.Bytes())
+	_, _ = w.Write(data)
 }

 func (s *Server) fileHandler(w http.ResponseWriter, r *http.Request) {