in uploadhandler.go [25:31]
func getTargetFilename(configBase string, slotBase string, requestedFilename string) string {
fileBase := path.Base(requestedFilename)
sanitizer := regexp.MustCompile("[^\\w\\d\\s.]")
sanitizedFileBase := sanitizer.ReplaceAllString(fileBase, "")
return path.Join(configBase, slotBase, sanitizedFileBase)
}