std::shared_ptr AccessPoint::create()

in mcrouter/lib/network/AccessPoint.cpp [122:189]
61 lines of code
15 McCabe index (conditional complexity)

std::shared_ptr<AccessPoint> AccessPoint::create(
    folly::StringPiece apString,
    mc_protocol_t defaultProtocol,
    SecurityMech defaultMech,
    uint16_t portOverride,
    bool defaultCompressed,
    uint32_t failureDomain,
    std::optional<uint16_t> taskId) {
  if (apString.empty()) {
    return nullptr;
  }

  folly::StringPiece host;
  bool unixDomainSocket = false;
  if (apString[0] == '[') {
    // IPv6
    auto closing = apString.find(']');
    if (closing == std::string::npos) {
      return nullptr;
    }
    host = apString.subpiece(1, closing - 1);
    apString.advance(closing + 1);
  } else {
    // IPv4 or hostname or UNIX domain socket
    if (apString.subpiece(0, 5) == "unix:") { // Unix domain socket
      unixDomainSocket = true;
      apString.advance(5);
    }
    auto colon = apString.find(':');
    if (colon == std::string::npos) {
      host = apString;
      apString = "";
    } else {
      host = apString.subpiece(0, colon);
      apString.advance(colon);
    }
  }

  if (host.empty()) {
    return nullptr;
  }

  try {
    folly::StringPiece port, protocol, encr, comp;
    if (unixDomainSocket) {
      port = "0";
      parseParts(apString, protocol, encr, comp);
      // Unix Domain Sockets with SSL is not supported.
      if (!encr.empty() && parseSecurityMech(encr) != SecurityMech::NONE) {
        return nullptr;
      }
    } else {
      parseParts(apString, port, protocol, encr, comp);
    }

    return std::make_shared<AccessPoint>(
        host,
        portOverride != 0 ? portOverride : folly::to<uint16_t>(port),
        protocol.empty() ? defaultProtocol : parseProtocol(protocol),
        encr.empty() ? defaultMech : parseSecurityMech(encr),
        comp.empty() ? defaultCompressed : parseCompressed(comp),
        unixDomainSocket,
        failureDomain,
        taskId);
  } catch (const std::exception&) {
    return nullptr;
  }
}