punchd/utils.nim

from net import
  IpAddress, IpAddressFamily, Port, `$`, newSocket, connect, close,
  getLocalAddr, parseIpAddress
from nativesockets import
  Domain, SockType, Protocol

# FIXME: getPrimaryAddr is not needed anymore once
# https://github.com/nim-lang/Nim/pull/15538 is released.
proc getPrimaryIPAddr*(dest = parseIpAddress("8.8.8.8")): IpAddress =
  ## Finds the local IP address, usually assigned to eth0 on LAN or wlan0 on WiFi,
  ## used to reach an external address. Useful to run local services.
  ##
  ## No traffic is sent.
  ##
  ## Supports IPv4 and v6.
  ## Raises OSError if external networking is not set up.
  ##
  ## .. code-block:: Nim
  ##   echo $getPrimaryIPAddr()  # "192.168.1.2"

  let socket =
    if dest.family == IpAddressFamily.IPv4:
      newSocket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)
    else:
      newSocket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)
  try:
    socket.connect($dest, 80.Port)
    result = socket.getLocalAddr()[0].parseIpAddress()
  finally:
    socket.close()