func parseRemotePeer()

in preinit_connection.go [183:228]
39 lines of code
9 McCabe index (conditional complexity)

func parseRemotePeer(p initParams, remoteAddr net.Addr) (PeerInfo, peerAddressComponents, error) {
	var (
		remotePeer        PeerInfo
		remotePeerAddress peerAddressComponents
		ok                bool
	)

	if remotePeer.HostPort, ok = p[InitParamHostPort]; !ok {
		return remotePeer, remotePeerAddress, fmt.Errorf("header %v is required", InitParamHostPort)
	}
	if remotePeer.ProcessName, ok = p[InitParamProcessName]; !ok {
		return remotePeer, remotePeerAddress, fmt.Errorf("header %v is required", InitParamProcessName)
	}

	// If the remote host:port is ephemeral, use the socket address as the
	// host:port and set IsEphemeral to true.
	if isEphemeralHostPort(remotePeer.HostPort) {
		remotePeer.HostPort = remoteAddr.String()
		remotePeer.IsEphemeral = true
	}

	remotePeer.Version.Language = p[InitParamTChannelLanguage]
	remotePeer.Version.LanguageVersion = p[InitParamTChannelLanguageVersion]
	remotePeer.Version.TChannelVersion = p[InitParamTChannelVersion]

	address := remotePeer.HostPort
	if sHost, sPort, err := net.SplitHostPort(address); err == nil {
		address = sHost
		if p, err := strconv.ParseUint(sPort, 10, 16); err == nil {
			remotePeerAddress.port = uint16(p)
		}
	}
	if address == "localhost" {
		remotePeerAddress.ipv4 = 127<<24 | 1
	} else if ip := net.ParseIP(address); ip != nil {
		if ip4 := ip.To4(); ip4 != nil {
			remotePeerAddress.ipv4 = binary.BigEndian.Uint32(ip4)
		} else {
			remotePeerAddress.ipv6 = address
		}
	} else {
		remotePeerAddress.hostname = address
	}

	return remotePeer, remotePeerAddress, nil
}