@Override
  public Optional<File> getFromOption(
      final CommandLine.ParseResult parseResult, final CommandLine commandLine) {
    final CommandLine.Model.OptionSpec configFileOption =
        parseResult.matchedOption(CONFIG_FILE_OPTION_NAME);
    try {
      File file = configFileOption.getter().get();
      if (!file.exists()) {
        throw new CommandLine.ParameterException(
            commandLine,
            String.format("Unable to read TOML configuration, file not found: %s", file));
      }
      return Optional.of(file);
    } catch (final Exception e) {
      throw new CommandLine.ParameterException(commandLine, e.getMessage(), e);
    }
  }
Gets the configuration file from the command line option.

@param parseResult the command line parse result
@param commandLine the command line
@return an Optional containing the configuration file, or an empty Optional if the
    configuration file was not specified in the command line option
app/src/main/java/org/hyperledger/besu/cli/util/ConfigFileFinder.java