create_topology_utils.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# License: GNU General Public License v2
# Author: thl-cmk[at]outlook[dot]com
# URL   : https://thl-cmk.hopto.org
# Date  : 2023-10-12
# File  : create_topology_utils.py

#
# options used
# -d --default
# -o --output-directory
# -s --seed-devices
# -u --user-data-file
# -v --version
# --check-user-data-only
# --data-source
# --debug
# --dont-compare
# --inventory-columns
# --keep-domain
# --keep
# --lldp
# --lowercase
# --min-age
# --path-in-inventory
# --time-format
# --uppercase

from os import environ
from json import dumps
import socket
from ast import literal_eval
from time import time as now_time
from tomllib import loads as toml_loads
from tomllib import TOMLDecodeError
from re import match as re_match
from pathlib import Path
from typing import List, Dict
from argparse import (
    Namespace as arg_Namespace,
    ArgumentParser,
    RawTextHelpFormatter,
)
from enum import Enum, unique


@unique
class ExitCodes(Enum):
    OK = 0
    BAD_OPTION_LIST = 1
    BAD_TOML_FORMAT = 3


script = '~/local/bin/network-topology/create_topology_data.py'
sample_seeds = 'Core01 Core02'
cdp_path = 'networking,cdp_cache'
cdp_columns = 'device_id,local_port,device_port'
cdp_label = 'inv_CDP'
lldp_path = 'networking,lldp_cache'
lldp_columns = 'system_name,local_port_num,port_id'
lldp_label = 'inv_LLDP'
user_data_file = 'create_topology_data.toml'


def get_data_form_live_status(query: str):
    address = f'{environ.get("OMD_ROOT")}/tmp/run/live'
    family = socket.AF_INET if type(address) is tuple else socket.AF_UNIX
    sock = socket.socket(family, socket.SOCK_STREAM)
    sock.connect(address)
    sock.sendall(query.encode())
    sock.shutdown(socket.SHUT_WR)
    chunks = []
    while len(chunks) == 0 or chunks[-1] != "":
        chunks.append(sock.recv(4096).decode())
    sock.close()
    if len(chunks):
        reply = "".join(chunks).strip()
        reply = literal_eval(reply)
        if reply != [[b'']]:
            return reply


def get_data_from_toml(file: str, debug: bool = False) -> Dict:
    data = {}
    toml_file = Path(file)
    if toml_file.exists():
        try:
            data = toml_loads(toml_file.read_text())
        except TOMLDecodeError as e:
            print(
                f'ERROR: data file {toml_file} is not in valid TOML format! ({e}), (see https://toml.io/en/)')
            exit(code=ExitCodes.BAD_TOML_FORMAT)
    else:
        print(f'WARNING: User data {file} not found.')
    if debug:
        print(f'TOML file read: {file}')
        print(f'Data from toml file: {data}')
    return data


def rm_tree(root: Path):
    # safety
    if not str(root).startswith(f'{environ["OMD_ROOT"]}/var/topology_data'):
        print(f"WARNING: bad path to remove, {str(root)}, don\'t delete it.")
        return
    for p in root.iterdir():
        if p.is_dir():
            rm_tree(p)
        else:
            p.unlink()
    root.rmdir()


def remove_old_data(keep: int, min_age: int, path: Path, protected: List[str], debug: bool = False):
    default_topo = path.joinpath('default')
    directories = [str(directory) for directory in list(path.iterdir())]
    # keep default top
    if str(default_topo) in directories:
        directories.remove(str(default_topo))
        keep -= 1
        if default_topo.is_symlink():
            try:
                directories.remove(str(default_topo.readlink()))
            except ValueError:
                pass

    # keep protected topologies
    for directory in protected:
        try:
            directories.remove(str(path.joinpath(directory)))
        except ValueError as e:
            if debug:
                print(e)
                print(directory)
                print(str(path.joinpath(directory)))
                print(directories)
        else:
            print(f'Protected topology: {directory}, will not be deleted.')

    if len(directories) < keep < 1:
        return

    topo_by_age = {}

    for directory in directories:
        if Path(directory).is_dir():
            topo_by_age[Path(directory).stat().st_ctime] = directory

    topo_age = list(topo_by_age.keys())
    topo_age.sort()

    while len(topo_by_age) > keep:
        if min_age * 86400 > now_time() - topo_age[0]:
            print(f'Topology "{Path(topo_by_age[topo_age[0]]).name}" not older then {min_age} day(s). not deleted.')
            return
        print(f'delete old topology: {topo_by_age[topo_age[0]]}')
        rm_tree(Path(topo_by_age[topo_age[0]]))
        topo_by_age.pop(topo_age[0])
        topo_age.pop(0)


def save_data_to_file(data: Dict, path: str, file: str, make_default: bool):
    """
    Save the data as json file.
    Args:
        data: the topology data
        path: the path were to save the dat
        file: the file name to save  data in
        make_default: if True, create the symlink "default" with path as target

    Returns:
        None
    """

    path_file = f'{path}/{file}'
    save_file = Path(f'{path_file}')
    save_file.parent.mkdir(exist_ok=True, parents=True)
    save_file.write_text(dumps(data))
    if make_default:
        parent_path = Path(f'{path}').parent
        Path(f'{parent_path}/default').unlink(missing_ok=True)
        Path(f'{parent_path}/default').symlink_to(target=Path(path), target_is_directory=True)


def save_topology(
        data: dict,
        base_directory: str,
        output_directory: str,
        dont_compare: bool,
        make_default: bool,
        topology_file_name: str,
):
    path = f'{base_directory}/{output_directory}'

    def _save():
        save_data_to_file(
            data=data,
            path=path,
            file=topology_file_name,
            make_default=make_default,
        )

    if dont_compare:
        _save()
    else:
        if not is_equal_with_default(
                data=data,
                file=f'{base_directory}/default/{topology_file_name}'
        ):
            _save()
        else:
            print(
                'Topology matches default topology, not saved! Use "--dont-compare" to save identical topologies.'
            )


def is_mac_address(mac_address: str, debug: bool = False) -> bool:
    """
    Checks if mac_address is a valid MAC address. Will only accept MAC address in the form "AA:BB:CC:DD:EE:FF"
    (lower case is also ok).
    Args:
        mac_address: the MAC address to check
        debug: optional. If True the result of the function will be printed to stdout

    Returns:
        True if mac_address is a valid MAC address
        False if mac_address not a valid MAC address
    """
    re_mac_pattern = '([0-9A-Z]{2}\\:){5}[0-9A-Z]{2}'
    if re_match(re_mac_pattern, mac_address.upper()):
        if debug:
            print(f'mac: {mac_address}, match')
        return True
    else:
        if debug:
            print(f'mac: {mac_address}, no match')
        return False


def is_list_of_str_equal(list1: List[str], list2: List[str]) -> bool:
    """
    Compares two list of strings. Before compared the list will internal sorted.
    Args:
        list1:
        list2:

    Returns:
        True if both lists match
        False if they don't match
    """
    tmp_list1 = list1.copy()
    tmp_list2 = list2.copy()
    tmp_list1.sort()
    tmp_list2.sort()
    return tmp_list1 == tmp_list2


def merge_topologies(topo_pri: Dict, topo_sec: Dict) -> Dict:
    """
    Merge dict_prim into dict_sec
    Args:
        topo_pri: data of dict_pri will overwrite the data in dict_sec
        topo_sec: dict where the data of dict_pri will be merged to

    Returns:
        Dict: topo_sec that contains merged data from top_sec and top_pri
    """
    keys_pri = list(topo_pri.keys())

    # first transfer all completely missing items from dict_prim to dict_sec
    for key in keys_pri:
        if key not in topo_sec.keys():
            topo_sec[key] = topo_pri[key]
        else:
            topo_sec[key]['connections'].update(topo_pri[key].get('connections', {}))
            topo_sec[key]['interfaces'] = list(set((topo_sec[key]['interfaces'] + topo_pri[key].get('interfaces', []))))
        topo_pri.pop(key)
    return topo_sec


def compare_dicts(dict1: Dict, dict2: Dict) -> bool:
    # check top level keys
    if not is_list_of_str_equal(list(dict1.keys()), list(dict2.keys())):
        # print('top level dont match')
        # print(f'dict1: {list(dict1.keys())}')
        # print(f'dict1: {list(dict2.keys())}')
        return False

    for key, value in dict1.items():
        _type = type(value)
        if _type == dict:
            if not compare_dicts(value, dict2[key]):
                return False
        elif _type == list:
            if not is_list_of_str_equal(value, dict2[key]):
                # print(f'list1: {value}')
                # print(f'list2: {dict2[key]}')
                return False
        elif _type == str:
            if not value == dict2[key]:
                # print('value dont match')
                # print(f'value1: {value}')
                # print(f'value2 {dict2[key]}')
                return False
        else:
            return False

    return True


def is_equal_with_default(data: Dict, file: str) -> bool:
    default_file = Path(file)
    if default_file.exists():
        default_data = literal_eval(default_file.read_text())
        return compare_dicts(data, default_data)


def parse_arguments(create_topology_version: str) -> arg_Namespace:
    parser = ArgumentParser(
        prog='create_topology_data.py',
        description='This script creates the topology data file needed for the Checkmk "network_visualization"\n'
                    'plugin by Andreas Boesl and schnetz. For more information see\n'
                    'the announcement from schnetz: https://forum.checkmk.com/t/network-visualization/41680\n'
                    'and the plugin on the Exchange: https://exchange.checkmk.com/p/network-visualization .\n'
                    '\n'
                    'The required inventory data can be created with my inventory plugins:\n'
                    'CDP: https://thl-cmk.hopto.org/gitlab/checkmk/vendor-independent/inventory/inv_cdp_cache\n'
                    'LLDP: https://thl-cmk.hopto.org/gitlab/checkmk/vendor-independent/inventory/inv_lldp_cache\n'
                    '\n'
                    f'\nVersion: {create_topology_version} | Written by: thl-cmk\n'
                    f'for more information see: https://thl-cmk.hopto.org',
        formatter_class=RawTextHelpFormatter,
        epilog='Usage:\n'
               'for CDP (the default):\n'
               f'{script} -s {sample_seeds} -d\n'
               'for LLDP:\n'
               f'{script} -s {sample_seeds} -d --lldp\n',
    )
    command_group = parser.add_mutually_exclusive_group()

    parser.add_argument(
        '-d', '--default', default=False, action='store_const', const=True,
        help='Set the created topology data as default',
    )
    parser.add_argument(
        '-m', '--merge',
        nargs=2,
        choices=['CDP', 'LLDP'],
        help=f'Merge topologies. This runs the topology creation for CDP and LLDP.\n'
             f'The topologies are then merged in the specified order.\n'
             f'I.e. -m CDP LLDP merges the CDP topology into the LLDP topology, overwriting\n'
             f'the LLDP data in case there are conflicts.\n'
             f'NOTE: static connection data from the user file will always merged with the\n'
             f' highest priority',
    )
    parser.add_argument(
        '-o', '--output-directory', type=str,
        help='Directory name where to save the topology data.\n'
             'I.e.: my_topology. Default is the actual date/time\n'
             'in "--time-format" format.\n'
             'NOTE: the directory is a sub directory under "~/var/topology_data/"',
    )
    parser.add_argument(
        '-s', '--seed-devices', type=str, nargs='+',
        help=f'List of devices to start the topology discovery from.\n'
             f'I.e. {sample_seeds}',
    )
    parser.add_argument(
        '-u', '--user-data-file', type=str,
        help='Set the name uf the user provided data file\n'
             'Default is ~local/bin/topology_data/create_topology_data.toml\n',
    )
    parser.add_argument(
        '-v', '--version', default=False, action='store_const', const=True,
        help='Print version of this script and exit',
    )
    parser.add_argument(
        '--check-user-data-only', default=False, action='store_const', const=True,
        help=f'Only tries to read/parse the user data from {user_data_file} and exits.',
    )
    parser.add_argument(
        '--data-source', type=str,
        help=f'The source from which the topology data originates.\n'
             f'I.e. {cdp_label} for CDP data from the inventory.\n'
             'NOTE: right now this only an unused label.',
    )
    parser.add_argument(
        '--debug', default=False, action='store_const', const=True,
        help='Print debug information',
    )
    parser.add_argument(
        '--dont-compare', default=False, action='store_const', const=True,
        help='Do not compare the actual topology data with the default topology\n'
             'data. By default, the actual topology is compared with the default\n'
             'topology. If the data matches, the actual topology is not saved.\n'
             'So, if you run this tool in a cron job, a new topology will be\n'
             'created only if there was a change, unless you use "--dont-compare".'
    )
    parser.add_argument(
        '--inventory-columns', type=str,
        help=f'Columns used from the inventory data.\n'
             f'I.e. "{cdp_columns}"\n'
             'NOTE: the columns must be in the order: neighbour, local_port,\n'
             'neighbour_port',
    )
    parser.add_argument(
        '--keep-domain', default=False, action='store_const', const=True,
        help='Do not remove the domain name from the neighbor name',
    )
    parser.add_argument(
        '--keep', type=int,
        help=f'Number of topologies to keep. The oldest topologies above keep\n'
             f'max will be deleted. The minimum value for --keep is 1.\n'
             f'NOTE: The default topologies will be always kept.\n'
    )
    parser.add_argument(
        '--lldp', default=False, action='store_const', const=True,
        help=f'Sets data source to {lldp_label}, inventory path \n'
             f'to "{lldp_path}" and columns\n'
             f'to "{lldp_columns}"',
    )
    command_group.add_argument(
        '--lowercase', default=False, action='store_const', const=True,
        help='Change neighbour names to all lower case',
    )
    parser.add_argument(
        '--min-age', type=int,
        help=f'The minimum number of days before a topology is deleted\n'
             f'by "--keep".\n'
             f'NOTE: Topologies that are not older than 1 days are always kept.',
    )
    parser.add_argument(
        '--path-in-inventory', type=str,
        help=f'Checkmk inventory path to the topology data.\n'
             f'I.e. "{cdp_path}"',
    )
    parser.add_argument(
        '--time-format', type=str,
        help='Format string to render the time. (default: %%Y-%%m-%%dT%%H:%%M:%%S.%%m)',
    )
    command_group.add_argument(
        '--uppercase', default=False, action='store_const', const=True,
        help='Change neighbour names to all upper case',
    )
    return parser.parse_args()