Function fsFile

context.go:674–700

(c *Context, file string, filesystem fs.FS)

}

func fsFile(c *Context, file string, filesystem fs.FS) error {
	file = path.Clean(file) // `os.Open` and `os.DirFs.Open()` behave differently, later does not like ``, `.`, `..` at all, but we allowed those now need to clean
	f, err := filesystem.Open(file)
	if err != nil {
		return ErrNotFound
	}
	defer f.Close()

	fi, _ := f.Stat()
	if fi.IsDir() {
		file = filepath.ToSlash(filepath.Join(file, indexPage)) // ToSlash is necessary for Windows. fs.Open and os.Open are different in that aspect.
		f, err = filesystem.Open(file)
		if err != nil {
			return ErrNotFound
		}
		defer f.Close()
		if fi, err = f.Stat(); err != nil {
			return err
		}
	}
	ff, ok := f.(io.ReadSeeker)
	if !ok {
		return errors.New("file does not implement io.ReadSeeker")
	}
	http.ServeContent(c.Response(), c.Request(), fi.Name(), fi.ModTime(), ff)
	return nil
}

// Attachment sends a response as attachment, prompting client to save the file.
//