[Enhancement] Add IPv6 Capabilities to tcp_ping

[gcasella]

Hey!

I'd like to propose adding IPv6 capabilities to the https://github.com/dmulyalin/nornir-salt/blob/master/nornir_salt/plugins/tasks/tcp_ping.py file.

This is my suggestion:

• added the function socketType() -- this will use the python ipaddress package to determine if a valid IPv4 or IPv6 address was entered. If there was a valid address it will return back either socket.AF_INET or socket.AF_INET6 and raise an exception if an invalid IP was entered.

• Adding the two lines below will open the socket on either IPv4 or IPv6 depending on the type of host that was entered in

socket_inet = socketType(host)
s = socket.socket(socket_inet)

I tested this out in normal python, but did not actually do a test of it yet within nornir_salt, i don't have a full development zone for nornir_salt to test this out in yet.

(I'm not sure if this type of logic will be required elsewhere)

Thanks!

"""
tcp_ping
########

Tests connection to a TCP port trying to establish a three way
handshake. Useful for network discovery or testing.

tcp_ping sample usage
=====================

Sample code to run ``tcp_ping`` task::

    import pprint
    from nornir import InitNornir
    from nornir_salt.plugins.tasks import tcp_ping
    from nornir_salt.plugins.functions import ResultSerializer

    nr = InitNornir(config_file="config.yaml")

    result = NornirObj.run(
        task=tcp_ping,
        ports=[22]
    )

    result_dictionary = ResultSerializer(result)

    pprint.pprint(result_dictionary)

    # prints:
    #
    # {'IOL1': {'tcp_ping': {22: True}},
    #  'IOL2': {'tcp_ping': {22: True}}}


tcp_ping returns
================

Returns dictionary of port numbers as keys with True/False as values

tcp_ping reference
==================

.. autofunction:: nornir_salt.plugins.tasks.tcp_ping.tcp_ping
"""
import logging
import socket
from typing import Optional, List

from nornir.core.task import Result, Task

from ipaddress import ip_address, IPv4Address

log = logging.getLogger(__name__)


def socketType(IP: str):
    try:
        return socket.AF_INET if type(ip_address(IP)) is IPv4Address else socket.AF_INET6
    except ValueError:
        return Exception(f"Invalid format for {IP} provided.")

def tcp_ping(
    task: Task, ports: List[int] = None, timeout: int = 1, host: Optional[str] = None
) -> Result:
    """
    :param ports: list of int, optional, tcp ports to ping, defaults to host's port or 22
    :param timeout: int, optional, connection timeout, defaults to 1
    :param host: string, optional, address to TCP ping, defaults to hosts' ``hostname`` value
    :returns: dictionary of port numbers as keys with True/False as values
    """
    ports = ports or []

    if not ports:
        ports = [int(task.host.port) if task.host.port else 22]
    elif isinstance(ports, int):
        ports = [ports]

    if isinstance(ports, list):
        if not all(isinstance(port, int) for port in ports):
            raise ValueError("Invalid value for 'ports'")
    else:
        raise ValueError("Invalid value for 'ports'")

    host = host or task.host.hostname

    result = {}
    for port in ports:
        socket_inet = socketType(host)
        s = socket.socket(socket_inet)
        s.settimeout(timeout)
        try:
            status = s.connect_ex((host, port))
            if status == 0:
                connection = True
            else:
                connection = False
        except (socket.gaierror, socket.timeout, socket.error):
            connection = False
        finally:
            s.close()
        result[port] = connection

    return Result(host=task.host, result=result)