utils.py 文件源码

def get_free_port(address, initial_port):
    """Find an unused TCP port in a specified range. This should not
      be used in misson-critical applications - a race condition may
      occur if someone grabs the port before caller of this function
      has chance to use it.
      Parameters:
          address       (string): an ip address of interface to use
          initial_port  (int)   : port to start iteration with
      Return:
          iterator that will return next unused port on a specified
            interface
    """

    try:
        # On OSX this function requires root privileges
        psutil.net_connections()
    except psutil.AccessDenied:
        return count(initial_port)

    def _unused_ports():
        for port in count(initial_port):
            # check if the port is being used
            connect_using_port = (
                conn
                for conn in psutil.net_connections()
                if hasattr(conn, 'laddr') and
                conn.laddr[0] == address and
                conn.laddr[1] == port
            )

            # only generate unused ports
            if not any(connect_using_port):
                yield port

    return _unused_ports()