update auf public download

cmd/unified/main.go

@@ -62,11 +62,13 @@ func loadConfig() AppConfig {
 	}
 
 	return AppConfig{
-		HTTPAddr:  httpAddr,
-		APIKey:    apiKey,
-		AdminUser: adminUser,
-		AdminPass: adminPass,
-		Mesh:      m,
+		HTTPAddr:        httpAddr,
+		APIKey:          apiKey,
+		AdminUser:       adminUser,
+		AdminPass:       adminPass,
+		Mesh:            m,
+		PublicDownloads: parseBoolEnv("PUBLIC_DOWNLOADS", false),
+		PublicPath:      getenvDefault("PUBLIC_DOWNLOAD_PATH", "/dl"),
 	}
 }
 
@@ -137,6 +139,9 @@ type AppConfig struct {
 	AdminUser string
 	AdminPass string
 	Mesh      mesh.Config
+
+	PublicDownloads bool   // ENV: PUBLIC_DOWNLOADS (default false)
+	PublicPath      string // ENV: PUBLIC_DOWNLOAD_PATH (default "/dl")
 }
 
 /*** Middleware ***/
@@ -455,6 +460,10 @@ func main() {
 	apiFiles(apiMux, st, blobs, mnode)
 	root.Handle("/api/", authMiddleware(cfg.APIKey, apiMux))
 
+	if cfg.PublicDownloads {
+		registerPublicDownloads(root, blobs, mnode, cfg.PublicPath)
+	}
+
 	// Admin-UI (optional BasicAuth via ADMIN_USER/ADMIN_PASS)
 	adminRoot := http.NewServeMux()
 	admin.Register(adminRoot, admin.Deps{Store: st, Mesh: mnode, Blob: blobs})
@@ -502,3 +511,78 @@ func main() {
 	_ = mnode.Close(ctx)
 	log.Println("shutdown complete")
 }
+
+// Public: GET {base}/{id}
+// Beispiel: /dl/1
+func registerPublicDownloads(mux *http.ServeMux, blobs blobfs.Store, meshNode *mesh.Node, base string) {
+	if !strings.HasPrefix(base, "/") {
+		base = "/" + base
+	}
+	mux.HandleFunc(base+"/", func(w http.ResponseWriter, r *http.Request) {
+		idStr := strings.TrimPrefix(r.URL.Path, base+"/")
+		if idStr == "" {
+			http.NotFound(w, r)
+			return
+		}
+		id, err := strconv.ParseInt(idStr, 10, 64)
+		if err != nil || id <= 0 {
+			http.NotFound(w, r)
+			return
+		}
+
+		// 1) lokal versuchen
+		if rc, meta, err := blobs.Open(r.Context(), id); err == nil {
+			defer rc.Close()
+			serveBlob(w, r, rc, meta)
+			return
+		}
+
+		// 2) aus dem Mesh ziehen (signiert) und lokal cachen
+		rrc, name, _, _, err := meshNode.FetchBlobAny(r.Context(), id)
+		if err != nil {
+			http.NotFound(w, r)
+			return
+		}
+		defer rrc.Close()
+		if _, err := blobs.Save(r.Context(), id, name, rrc); err != nil {
+			http.Error(w, "cache failed", http.StatusInternalServerError)
+			return
+		}
+
+		// 3) erneut lokal öffnen (saubere Meta/Größe/CT)
+		lrc, meta, err := blobs.Open(r.Context(), id)
+		if err != nil {
+			http.Error(w, "open failed", http.StatusInternalServerError)
+			return
+		}
+		defer lrc.Close()
+		serveBlob(w, r, lrc, meta)
+	})
+}
+
+// Hilfsfunktion: setzt sinnvolle Header und streamt die Datei
+func serveBlob(w http.ResponseWriter, r *http.Request, rc io.ReadSeeker, meta blobfs.Meta) {
+	// Caching (einfach): ETag = SHA256
+	if meta.SHA256 != "" {
+		etag := `W/"` + meta.SHA256 + `"`
+		if inm := r.Header.Get("If-None-Match"); inm == etag {
+			w.WriteHeader(http.StatusNotModified)
+			return
+		}
+		w.Header().Set("ETag", etag)
+	}
+
+	// Standard-Header
+	if meta.ContentType == "" {
+		meta.ContentType = "application/octet-stream"
+	}
+	w.Header().Set("Content-Type", meta.ContentType)
+	w.Header().Set("Content-Length", strconv.FormatInt(meta.Size, 10))
+	w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, meta.Name))
+	w.Header().Set("Access-Control-Expose-Headers", "Content-Disposition") // für Browser-JS
+	w.Header().Set("X-Robots-Tag", "noindex")
+
+	// (Optional) einfache Range-Unterstützung weglassen, um’s schlank zu halten
+	// Stream
+	_, _ = io.Copy(w, rc)
+}