isc dhcpd plugin added

diff --git a/python.d/isc_dhcdp.chart.py b/python.d/isc_dhcdp.chart.py
new file mode 100644 (file)
index 0000000..82b2c45
--- /dev/null
+++ b/python.d/isc_dhcdp.chart.py
@@ -0,0 +1,109 @@
+# -*- coding: utf-8 -*-
+# Description: isc dhcpd lease netdata python.d module
+# Author: l2isbad
+
+from base import SimpleService
+from re import compile, search
+from time import mktime, strptime, gmtime
+try:
+    from ipaddress import IPv4Address as ipaddress
+    from ipaddress import ip_network
+    have_ipaddress = True
+except ImportError:
+    have_ipaddress = False
+
+priority = 60000
+retries = 60
+update_every = 60
+
+class Service(SimpleService):
+    def __init__(self, configuration=None, name=None):
+        SimpleService.__init__(self, configuration=configuration, name=name)
+        self.leases_path = self.configuration.get('leases_path', '/var/lib/dhcp/dhcpd.leases')
+        self.pools = self.configuration.get('pools')
+
+        # Will work only with 'default' db-time-format (weekday year/month/day hour:minute:second)
+        # TODO: update the regex to parse correctly 'local' db-time-format
+        # (epoch <seconds-since-epoch>; # <day-name> <month-name> <day-number> <hours>:<minutes>:<seconds> <year>)
+        # Also only ipv4 supported
+        self.regex = compile(r'(\d+(?:\.\d+){3}).*?((?<=ends )[0-9].*?(?=;))')
+
+    def check(self):
+        if not self._get_raw_data():
+            self.error('Make sure leases_path is correct and dhcpd.leases is readable by netdata')
+            return False
+        elif not have_ipaddress:
+            self.error('No ipaddress module. Please install (py2-ipaddress in case of python2)')
+            return False
+        else:
+            try:
+                self.pools = self.pools.split()
+                if not [ip_network(pool) for pool in self.pools]:
+                    self.error('Pools list is empty')
+                    return False
+            except (ValueError, IndexError, AttributeError, SyntaxError):
+                self.error('Pools configurations is incorrect')
+                return False
+            
+            # Creating dynamic charts
+            self.order = ['utilization']
+            self.definitions = {'utilization': {'options': [None, 'Pools utilization', 'used %', 'Utulization', 'isc_dhcpd.util', 'line'], 'lines': []} }
+            for pool in self.pools:
+                self.definitions['utilization']['lines'].append([''.join(['ut_', pool]), pool, 'absolute'])
+                self.order.append(''.join(['leases_', pool]))
+                self.definitions[''.join(['leases_', pool])] = \
+                    {'options': [None, 'Active leases', 'leases', 'Leases', 'isc_dhcpd.lease', 'area'], 
+                     'lines': [[''.join(['le_', pool]), pool, 'absolute']]}
+
+            self.info('Plugin was started succesfully')
+            return True
+
+    def _get_raw_data(self):
+        """
+        Open log file
+        :return: str
+        """
+        try:
+            with open(self.leases_path, 'rt') as leases:
+                result = leases.read()
+        except Exception:
+            return None
+        else:
+            return result
+
+    def _get_data(self):
+        """
+        Parse dhcpd.leases file.
+        """
+        raw_leases = self._get_raw_data()
+        all_leases = dict(self.regex.findall(' '.join(raw_leases.split())))
+
+        if  not all_leases:
+            self.error('Cant parse leases file correctly')
+            return None
+
+        # Result: [active binding, active binding....]. (Expire time (ends date;) - current time > 0)
+        active_leases = [k for k, v in all_leases.items() if is_bind_active(all_leases[k])]
+
+        # Result: {pool: number of active bindings in pool, ...}
+        pools_count = {pool: len([lease for lease in active_leases if is_address_in(lease, pool)]) for pool in self.pools}
+
+        # Result: {pool: number of host ip addresses in pool, }
+        pools_max = {pool: (2 ** (32 - int(pool.split('/')[1])) - 2) for pool in self.pools}
+
+        # Result: {pool: % utilization, ....} (percent)
+        pools_util = {pool:int(round(float(pools_count[pool]) / pools_max[pool] * 100, 0)) for pool in self.pools}
+
+        # Bulding dicts to send to netdata
+        final_count = {''.join(['le_', k]): v for k, v in pools_count.items()}
+        final_util = {''.join(['ut_', k]): v for k, v in pools_util.items()}
+
+        final_count.update(final_util)
+
+        return final_count
+    
+def is_bind_active(binding):
+    return mktime(strptime(binding, '%w %Y/%m/%d %H:%M:%S')) - mktime(gmtime()) > 0
+
+def is_address_in(address, pool):
+    return ipaddress(address) in ip_network(pool)