AlistGo/alist · error

negative content size not supported

Error message

negative content size not supported

What it means

Error "negative content size not supported" thrown in AlistGo/alist.

Source

Thrown at internal/net/serve.go:66

// modtime to decide whether the content needs to be sent at all.
//
// The content's RangeReadCloser method must work: ServeHTTP gives a range,
// caller will give the reader for that Range.
//
// If the caller has set w's ETag header formatted per RFC 7232, section 2.3,
// ServeHTTP uses it to handle requests using If-Match, If-None-Match, or If-Range.
func ServeHTTP(w http.ResponseWriter, r *http.Request, name string, modTime time.Time, size int64, RangeReadCloser model.RangeReadCloserIF) error {
	defer RangeReadCloser.Close()
	setLastModified(w, modTime)
	done, rangeReq := checkPreconditions(w, r, modTime)
	if done {
		return nil
	}

	if size < 0 {
		// since too many functions need file size to work,
		// will not implement the support of unknown file size here
		http.Error(w, "negative content size not supported", http.StatusInternalServerError)
		return nil
	}

	code := http.StatusOK

	// If Content-Type isn't set, use the file's extension to find it, but
	// if the Content-Type is unset explicitly, do not sniff the type.
	contentTypes, haveType := w.Header()["Content-Type"]
	var contentType string
	if !haveType {
		contentType = mime.TypeByExtension(filepath.Ext(name))
		if contentType == "" {
			// most modern application can handle the default contentType
			contentType = "application/octet-stream"
		}
		w.Header().Set("Content-Type", contentType)
	} else if len(contentTypes) > 0 {
		contentType = contentTypes[0]

View on GitHub (pinned to 843d9dc814)

Solutions

1. This operation is not supported by the driver/backend; use a supported alternative or a different storage driver.

When it happens

Trigger: Thrown at internal/net/serve.go:66 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of AlistGo/alist@843d9dc814 (2026-08-15). Data as JSON: /api/errors/94d039a2857949b4. Report an issue: GitHub.