init

main.go

@@ -0,0 +1,84 @@
+// fileserver.go
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+func main() {
+	base := getenv("SERVE_DIR", ".")
+	addr := getenv("SERVE_ADDR", ":8080")
+	forceAtt := parseBoolEnv(getenv("FORCE_ATTACHMENT", "1")) // 1/true = Download erzwingen
+
+	fsys := http.Dir(base)
+
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		// Nur GET/HEAD
+		if r.Method != http.MethodGet && r.Method != http.MethodHead {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+
+		// Keine Startseite / kein Listing
+		clean := path.Clean("/" + r.URL.Path)
+		if clean == "/" {
+			http.NotFound(w, r)
+			return
+		}
+
+		// Sicher relativ zum SERVE_DIR öffnen (http.Dir verhindert "..")
+		f, err := fsys.Open(clean)
+		if err != nil {
+			http.NotFound(w, r)
+			return
+		}
+		defer f.Close()
+
+		info, err := f.Stat()
+		if err != nil || info.IsDir() {
+			http.NotFound(w, r)
+			return
+		}
+
+		if forceAtt {
+			w.Header().Set("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, filepath.Base(clean)))
+			w.Header().Set("Content-Type", "application/octet-stream")
+			w.Header().Set("X-Content-Type-Options", "nosniff")
+		}
+
+		// Unterstützt Range/If-Modified-Since/HEAD
+		http.ServeContent(w, r, info.Name(), modTimeSafe(info.ModTime()), f)
+	})
+
+	log.Printf("Serving files from %q on %s (attachment=%v)", base, addr, forceAtt)
+	log.Fatal(http.ListenAndServe(addr, nil))
+}
+
+func getenv(k, def string) string {
+	if v, ok := os.LookupEnv(k); ok {
+		return v
+	}
+	return def
+}
+
+func parseBoolEnv(v string) bool {
+	v = strings.TrimSpace(strings.ToLower(v))
+	return v == "1" || v == "true" || v == "yes" || v == "on"
+}
+
+func modTimeSafe(t time.Time) time.Time {
+	if t.Before(time.Date(1980, 1, 1, 0, 0, 0, 0, time.UTC)) {
+		return time.Date(1980, 1, 1, 0, 0, 0, 0, time.UTC)
+	}
+	if t.After(time.Date(2107, 12, 31, 23, 59, 59, 0, time.UTC)) {
+		return time.Date(2107, 12, 31, 23, 59, 59, 0, time.UTC)
+	}
+	return t
+}