Settings parseOptions()

in mcrouter/tools/mcpiper/main.cpp [58:173]

• 97 lines of code
• 4 McCabe index (conditional complexity)

Settings parseOptions(int argc, char** argv) {
  Settings settings;

  namespace po = boost::program_options;

  // Named options
  po::options_description namedOpts("Allowed options");
  namedOpts.add_options()("help,h", "Print this help message.")(
      "version", "Print mcpiper version and exit.")(
      "fifo-root,f",
      po::value<std::string>(&settings.fifoRoot),
      "Path of mcrouter fifo's directory.")(
      "filename-pattern,P",
      po::value<std::string>(&settings.filenamePattern),
      "Basic regular expression (BRE) to match the name of the fifos.")(
      "host,H",
      po::value<std::string>(&settings.host),
      "Show only messages sent/received to provided IP address.")(
      "ignore-case,i",
      po::bool_switch(&settings.ignoreCase)->default_value(false),
      "Ignore case on search patterns")(
      "invert-match,v",
      po::bool_switch(&settings.invertMatch)->default_value(false),
      "Invert match")(
      "max-messages,n",
      po::value<uint32_t>(&settings.maxMessages),
      "Display only <arg> messages and exit.")(
      "num-after-match,A",
      po::value<uint32_t>(&settings.numAfterMatch),
      "Shows <arg> messages after a matched message.")(
      "port,p",
      po::value<uint16_t>(&settings.port),
      "Show only messages transmitted in provided port.")(
      "quiet,q",
      po::bool_switch(&settings.quiet)->default_value(false),
      "Doesn't display values.")(
      "time-format,t",
      po::value<std::string>(&settings.timeFormat),
      "Displays timestamp on every match; "
      "ARG is \"absolute\", \"diff\" or \"offset\".")(
      "value-min-size,m",
      po::value<uint32_t>(&settings.valueMinSize),
      "Minimum size of the value of messages to display")(
      "value-max-size,M",
      po::value<uint32_t>(&settings.valueMaxSize),
      "Maximum size of the value of messages to display")(
      "min-latency-us,l",
      po::value<int64_t>(&settings.minLatencyUs),
      "Minimum latency in micros of messages to display")(
      "protocol",
      po::value<std::string>(&settings.protocol),
      "Show only data transmitted in the provided protocol; "
      "ARG is \"ascii\" or \"caret\".")(
      "verbose",
      po::value<size_t>(&settings.verboseLevel),
      "Set verbose level")(
      "raw",
      po::bool_switch(&settings.raw)->default_value(false),
      "Prints raw data. Format: firstly size(8 bytes) then message. "
      "ASCII protocol is not supported")(
      "script",
      po::bool_switch(&settings.script)->default_value(false),
      "Machine-readable JSON output (useful for post-processing).");

  // Positional arguments - hidden from the help message
  po::options_description hiddenOpts("Hidden options");
  hiddenOpts.add_options()(
      "match-expression",
      po::value<std::string>(&settings.matchExpression),
      "Match expression");
  po::positional_options_description posArgs;
  posArgs.add("match-expression", 1);

  // Parse command line
  po::variables_map vm;
  try {
    // Build all options
    po::options_description allOpts;
    allOpts.add(namedOpts).add(hiddenOpts);

    // Parse
    po::store(
        po::command_line_parser(argc, argv)
            .options(allOpts)
            .positional(posArgs)
            .run(),
        vm);
    po::notify(vm);
  } catch (po::error& ex) {
    LOG(ERROR) << ex.what();
    exit(1);
  }

  // Handles help
  if (vm.count("help")) {
    std::cerr << getUsage(argv[0]);
    std::cerr << std::endl;

    // Print only named options
    namedOpts.print(std::cerr);
    exit(0);
  }

  if (vm.count("version")) {
    std::cerr << facebook::memcache::getVersion() << std::endl;
    exit(0);
  }

  // Handles constraints
  CHECK(!settings.fifoRoot.empty())
      << "Fifo's directory (--fifo-root) cannot be empty";

  FLAGS_v = settings.verboseLevel;

  return settings;
}