python.d/isc_dhcpd.chart.py

   1 # -*- coding: utf-8 -*-
   2 # Description: isc dhcpd lease netdata python.d module
   3 # Author: l2isbad
   4
   5 from base import SimpleService
   6 from re import compile
   7 from time import mktime, strptime, gmtime, time
   8 try:
   9     from ipaddress import IPv4Address as ipaddress
  10     from ipaddress import ip_network
  11     have_ipaddress = True
  12 except ImportError:
  13     have_ipaddress = False
  14
  15 priority = 60000
  16 retries = 60
  17 update_every = 60
  18
  19 class Service(SimpleService):
  20     def __init__(self, configuration=None, name=None):
  21         SimpleService.__init__(self, configuration=configuration, name=name)
  22         self.leases_path = self.configuration.get('leases_path', '/var/lib/dhcp/dhcpd.leases')
  23         self.pools = self.configuration.get('pools')
  24
  25         # Will work only with 'default' db-time-format (weekday year/month/day hour:minute:second)
  26         # TODO: update algorithm to parse correctly 'local' db-time-format
  27         # (epoch <seconds-since-epoch>; # <day-name> <month-name> <day-number> <hours>:<minutes>:<seconds> <year>)
  28         # Also only ipv4 supported
  29         self.regex = compile(r'\d+(?:\.\d+){3}')
  30
  31     def check(self):
  32         if not self._get_raw_data():
  33             self.error('Make sure leases_path is correct and leases log file is readable by netdata')
  34             return False
  35         elif not have_ipaddress:
  36             self.error('No ipaddress module. Please install (py2-ipaddress in case of python2)')
  37             return False
  38         else:
  39             try:
  40                 self.pools = self.pools.split()
  41                 if not [ip_network(pool) for pool in self.pools]:
  42                     self.error('Pools list is empty')
  43                     return False
  44             except (ValueError, IndexError, AttributeError, SyntaxError):
  45                 self.error('Pools configurations is incorrect')
  46                 return False
  47
  48             # Creating dynamic charts
  49             self.order = ['parse_time', 'utilization']
  50             self.definitions = {'utilization':
  51                                     {'options':
  52                                          [None, 'Pools utilization', 'used %', 'Utulization', 'isc_dhcpd.util', 'line'],
  53                                      'lines': []},
  54                                'parse_time':
  55                                    {'options':
  56                                         [None, 'Parse time', 'ms', 'Parse statistics', 'isc_dhcpd.parse', 'line'],
  57                                     'lines': [['ptime', 'time', 'absolute']]}}
  58             for pool in self.pools:
  59                 self.definitions['utilization']['lines'].append([''.join(['ut_', pool]), pool, 'absolute'])
  60                 self.order.append(''.join(['leases_', pool]))
  61                 self.definitions[''.join(['leases_', pool])] = \
  62                     {'options': [None, 'Active leases', 'leases', 'Leases', 'isc_dhcpd.lease', 'area'],
  63                      'lines': [[''.join(['le_', pool]), pool, 'absolute']]}
  64
  65             self.info('Plugin was started succesfully')
  66             return True
  67
  68     def _get_raw_data(self):
  69         """
  70         Parses log file
  71         :return: tuple(
  72                        [ipaddress, lease end time, ...],
  73                        length of list,
  74                        time to parse leases file
  75                       )
  76         """
  77         try:
  78             with open(self.leases_path, 'rt') as dhcp_leases:
  79                 raw_result = []
  80
  81                 time_start = time()
  82                 for line in dhcp_leases:
  83                     if line[0:3] == 'lea':
  84                         raw_result.append(self.regex.search(line).group())
  85                     elif line[2:6] == 'ends':
  86                         raw_result.append(line[7:28])
  87                     else:
  88                         continue
  89                 time_end = time()
  90                 file_parse_time = round((time_end - time_start) * 1000)
  91
  92         except Exception:
  93             return None
  94
  95         else:
  96             raw_result_length = len(raw_result)
  97             result = (raw_result, raw_result_length, file_parse_time)
  98             return result
  99
 100     def _get_data(self):
 101         """
 102         :return: dict
 103         """
 104         raw_leases = self._get_raw_data()
 105
 106         if not raw_leases:
 107             return None
 108
 109         # Result: {ipaddress: end lease time, ...}
 110         all_leases = dict(zip([raw_leases[0][_] for _ in range(0, raw_leases[1], 2)],
 111                               [raw_leases[0][_] for _ in range(1, raw_leases[1], 2)]))
 112
 113         # Result: [active binding, active binding....]. (Expire time (ends date;) - current time > 0)
 114         active_leases = [k for k, v in all_leases.items() if is_bind_active(all_leases[k])]
 115
 116         # Result: {pool: number of active bindings in pool, ...}
 117         pools_count = {pool: len([lease for lease in active_leases if is_address_in(lease, pool)])
 118                        for pool in self.pools}
 119
 120         # Result: {pool: number of host ip addresses in pool, ...}
 121         pools_max = {pool: (2 ** (32 - int(pool.split('/')[1])) - 2)
 122                      for pool in self.pools}
 123
 124         # Result: {pool: % utilization, ....} (percent)
 125         pools_util = {pool:int(round(float(pools_count[pool]) / pools_max[pool] * 100, 0))
 126                       for pool in self.pools}
 127
 128         # Bulding dicts to send to netdata
 129         final_count = {''.join(['le_', k]): v for k, v in pools_count.items()}
 130         final_util = {''.join(['ut_', k]): v for k, v in pools_util.items()}
 131
 132         to_netdata = {'ptime': int(raw_leases[2])}
 133         to_netdata.update(final_util)
 134         to_netdata.update(final_count)
 135
 136         return to_netdata
 137
 138 def is_bind_active(binding):
 139     return mktime(strptime(binding, '%w %Y/%m/%d %H:%M:%S')) - mktime(gmtime()) > 0
 140
 141 def is_address_in(address, pool):
 142     return ipaddress(address) in ip_network(pool)