AlistGo/alist · warning

invalid input file path: %w

Error message

invalid input file path: %w

What it means

Thrown by resizeImageToBufferWithFFmpegGo when sanitizeFilePath rejects the path of an image about to be resized for a thumbnail. sanitizeFilePath enforces four rules: the path must be absolute, must not contain shell metacharacters (;;&|`$<>!\n\r\x00), must be stat-able by the process, and must be a regular file. The wrapped error names which rule failed ('file path must be absolute', 'file path contains invalid characters', 'file path is not accessible', 'path is not a regular file').

Source

Thrown at drivers/local/util.go:69

	}
	if strings.ContainsAny(cleaned, ";&|`$<>!\n\r\x00") {
		return "", fmt.Errorf("file path contains invalid characters: %s", path)
	}
	info, err := os.Stat(cleaned)
	if err != nil {
		return "", fmt.Errorf("file path is not accessible: %w", err)
	}
	if !info.Mode().IsRegular() {
		return "", fmt.Errorf("path is not a regular file: %s", cleaned)
	}
	return cleaned, nil
}

// resizeImageToBufferWithFFmpegGo 使用 ffmpeg-go 调整图片大小并输出到内存缓冲区
func resizeImageToBufferWithFFmpegGo(inputFile string, width int, outputFormat string /* e.g., "image2pipe", "png_pipe", "mjpeg" */) (*bytes.Buffer, error) {
	sanitized, err := sanitizeFilePath(inputFile)
	if err != nil {
		return nil, fmt.Errorf("invalid input file path: %w", err)
	}
	inputFile = sanitized

	outBuffer := bytes.NewBuffer(nil)

	// Determine codec based on desired output format for piping
	// For generic image piping, 'image2' is often used with -f image2pipe
	// For specific formats to buffer, you might specify the codec directly
	var vcodec string
	switch outputFormat {
	case "png_pipe": // if you want to ensure PNG format in buffer
		vcodec = "png"
	case "mjpeg": // if you want to ensure JPEG format in buffer
		vcodec = "mjpeg"
		// default or "image2pipe" could leave codec choice more to ffmpeg or require -c:v later
	}

	outputArgs := ffmpeg.KwArgs{

View on GitHub (pinned to 843d9dc814)

Solutions

1. Check the wrapped error message to identify which sanitizeFilePath rule failed
2. If the path is relative, ensure the local driver's root and the object's GetPath() produce absolute paths
3. Rename files containing ; & | ` $ < > ! or newlines, or relax the metacharacter check if you trust the input (ffmpeg-go does not use a shell)
4. Verify the file still exists and is readable: stat <path> as the same user running the process

Example fix

// before: relative or metachar path passed through
imgBuf, err := resizeImageToBufferWithFFmpegGo(file.GetPath(), d.thumbPixel, "image2pipe")

// after: resolve to an absolute, cleaned path first and skip files known to be problematic
fullPath := file.GetPath()
if !filepath.IsAbs(fullPath) {
    fullPath = filepath.Join(d.RootFolderPath, fullPath)
}
imgBuf, err := resizeImageToBufferWithFFmpegGo(fullPath, d.thumbPixel, "image2pipe")
if err != nil {
    // fall back to no thumbnail rather than failing the listing
    return nil, nil, nil
}

func validThumbPath(path string) bool {
    abs, err := filepath.Abs(path)
    if err != nil {
        return false
    }
    info, err := os.Stat(abs)
    return err == nil && info.Mode().IsRegular()
}

In Go: imgBuf, err := resizeImageToBufferWithFFmpegGo(path, w, "image2pipe"); if err != nil { log thumbnail failure and degrade to a listing without thumbnails — never propagate to the caller of getThumb }

When it happens

Trigger: Calling getThumb on a local driver with useFFmpeg=true where the object's path is relative, contains a character like ';' or '$' or a newline in the filename, points to a symlink target that no longer exists, or points to a directory/fifo/device instead of a regular file.

Common situations: Filenames with shell metacharacters (e.g. 'photo;$1.png'), files deleted between directory listing and thumbnail request, permission-restricted mounts, or symlinked media directories on Windows volumes where ModeIrregular is set.

Related errors

• invalid video path: %w
• ffmpeg-go failed to resize image %s to buffer: %w
• ffmpeg-go produced empty buffer for %s
• failed to open image: %w
• failed to decode image: %w

AI-assisted analysis of AlistGo/alist@843d9dc814 (2026-08-15). Data as JSON: /api/errors/d194900e41c221fa. Report an issue: GitHub.