powerdns-admin/powerdnsadmin/lib/utils.py

import logging
import re
import json
import requests
import ipaddress
import idna

from collections.abc import Iterable
from distutils.version import StrictVersion
from urllib.parse import urlparse


def auth_from_url(url):
    auth = None
    parsed_url = urlparse(url).netloc
    if '@' in parsed_url:
        auth = parsed_url.split('@')[0].split(':')
        auth = requests.auth.HTTPBasicAuth(auth[0], auth[1])
    return auth


def fetch_remote(remote_url,
                 method='GET',
                 data=None,
                 accept=None,
                 params=None,
                 timeout=None,
                 headers=None,
                 verify=True):
    if data is not None and type(data) != str:
        data = json.dumps(data)

    verify = bool(verify)  # enforce type boolean

    our_headers = {
        'user-agent': 'powerdnsadmin/0',
        'pragma': 'no-cache',
        'cache-control': 'no-cache'
    }
    if accept is not None:
        our_headers['accept'] = accept
    if headers is not None:
        our_headers.update(headers)

    r = requests.request(method,
                         remote_url,
                         headers=headers,
                         verify=verify,
                         auth=auth_from_url(remote_url),
                         timeout=timeout,
                         data=data,
                         params=params)
    logging.debug(
        'Querying remote server "{0}" ({1}) finished with code {2} (took {3}s)'
        .format(remote_url, method, r.status_code, r.elapsed.total_seconds()))
    try:
        if r.status_code not in (200, 201, 204, 400, 409, 422):
            r.raise_for_status()
    except Exception as e:
        msg = "Returned status {0} and content {1}".format(r.status_code, r.text)
        raise RuntimeError('Error while fetching {0}. {1}'.format(
            remote_url, msg))

    return r


def fetch_json(remote_url,
               method='GET',
               data=None,
               params=None,
               headers=None,
               timeout=None,
               verify=True):
    r = fetch_remote(remote_url,
                     method=method,
                     data=data,
                     params=params,
                     headers=headers,
                     timeout=timeout,
                     verify=verify,
                     accept='application/json; q=1')

    if method == "DELETE":
        return True

    if r.status_code == 204:
        return {}
    elif r.status_code == 409:
        return {
            'error': 'Resource already exists or conflict',
            'http_code': r.status_code
        }

    try:
        assert ('json' in r.headers['content-type'])
    except Exception as e:
        raise RuntimeError(
            'Error while fetching {0}'.format(remote_url)) from e

    # don't use r.json here, as it will read from r.text, which will trigger
    # content encoding auto-detection in almost all cases, WHICH IS EXTREMELY
    # SLOOOOOOOOOOOOOOOOOOOOOOW. just don't.
    data = None
    try:
        data = json.loads(r.content.decode('utf-8'))
    except UnicodeDecodeError:
        # If the decoding fails, switch to slower but probably working .json()
        try:
            logging.warning("UTF-8 content.decode failed, switching to slower .json method")
            data = r.json()
        except Exception as e:
            raise e
    except Exception as e:
        raise RuntimeError(
            'Error while loading JSON data from {0}'.format(remote_url)) from e
    return data


def display_record_name(data):
    record_name, domain_name = data
    if record_name == domain_name:
        return '@'
    else:
        return re.sub('\.{}$'.format(domain_name), '', record_name)


def display_master_name(data):
    """
    input data: "[u'127.0.0.1', u'8.8.8.8']"
    """
    matches = re.findall(r'\'(.+?)\'', data)
    return ", ".join(matches)


def display_time(amount, units='s', remove_seconds=True):
    """
    Convert timestamp to normal time format
    """
    amount = int(amount)
    INTERVALS = [(lambda mlsec: divmod(mlsec, 1000), 'ms'),
                 (lambda seconds: divmod(seconds, 60), 's'),
                 (lambda minutes: divmod(minutes, 60), 'm'),
                 (lambda hours: divmod(hours, 24), 'h'),
                 (lambda days: divmod(days, 7), 'D'),
                 (lambda weeks: divmod(weeks, 4), 'W'),
                 (lambda years: divmod(years, 12), 'M'),
                 (lambda decades: divmod(decades, 10), 'Y')]

    for index_start, (interval, unit) in enumerate(INTERVALS):
        if unit == units:
            break

    amount_abrev = []
    last_index = 0
    amount_temp = amount
    for index, (formula,
                abrev) in enumerate(INTERVALS[index_start:len(INTERVALS)]):
        divmod_result = formula(amount_temp)
        amount_temp = divmod_result[0]
        amount_abrev.append((divmod_result[1], abrev))
        if divmod_result[1] > 0:
            last_index = index
    amount_abrev_partial = amount_abrev[0:last_index + 1]
    amount_abrev_partial.reverse()

    final_string = ''
    for amount, abrev in amount_abrev_partial:
        final_string += str(amount) + abrev + ' '

    if remove_seconds and 'm' in final_string:
        final_string = final_string[:final_string.rfind(' ')]
        return final_string[:final_string.rfind(' ')]

    return final_string


def pdns_api_extended_uri(version):
    """
    Check the pdns version
    """
    if StrictVersion(version) >= StrictVersion('4.0.0'):
        return "/api/v1"
    else:
        return ""


def display_setting_state(value):
    if value == 1:
        return "ON"
    elif value == 0:
        return "OFF"
    else:
        return "UNKNOWN"


def validate_ipaddress(address):
    try:
        ip = ipaddress.ip_address(address)
    except ValueError:
        pass
    else:
        if isinstance(ip, (ipaddress.IPv4Address, ipaddress.IPv6Address)):
            return [ip]
    return []


def pretty_json(data):
    return json.dumps(data, sort_keys=True, indent=4)


def ensure_list(l):
    if not l:
        l = []
    elif not isinstance(l, Iterable) or isinstance(l, str):
        l = [l]

    yield from l


class customBoxes:
    boxes = {
        "reverse": (" ", " "),
        "ip6arpa": ("ip6", "%.ip6.arpa"),
        "inaddrarpa": ("in-addr", "%.in-addr.arpa")
    }
    order = ["reverse", "ip6arpa", "inaddrarpa"]

def pretty_domain_name(value):
    """
    Display domain name in original format.
    If it is IDN domain (Punycode starts with xn--), do the
    idna decoding.
    Note that any part of the domain name can be individually punycoded
    """
    if isinstance(value, str):
        if value.startswith('xn--') \
        or value.find('.xn--') != -1:
            try:
                return to_idna(value, 'decode')
            except:
                raise Exception('Cannot decode IDN domain')
        else:
            return value
    else:
        raise Exception('Require the Punycode in string format')

def to_idna(value, action):
    splits = value.split()
    result = []
    if action == 'encode':
        for split in splits:
            try:
                # Try encoding to idna
                result.append(idna.encode(split).decode())
            except idna.IDNAError:
                result.append(split)
    elif action == 'decode':
        for split in splits:
            result.append(idna.decode(split))   
    else:
        raise Exception('No valid action received')
    return ' '.join(result)