NetSnmp

Complexity

Total Complexity

14

Size/Duplication

Total Lines	117
Duplicated Lines	69.23 %

Importance

Changes	2
Bugs	0	Features	0

3 Methods

Rating	Name	Duplication	Size	Complexity
A	poll()	0	6	1
F	check()	65	66	12
A	__init__()	14	15	1

# -*- coding: utf-8 -*-
"""SNMP metric reader for /proc on Linux."""
import time
from collections import deque

import plumd
from plumd.util import Differential
from plumd.util import Filter

__author__ = 'Kenny Freeman'
__email__ = 'kenny.freeman@gmail.com'
__license__ = "ISCL"
__docformat__ = 'reStructuredText'


# todo: switch from list with pop(0) to deque
class NetSnmp(plumd.Reader):
    """Plugin to measure various kernel metrics from /proc."""

    defaults = {
        'poll.interval': 10,
        'proc_path': '/proc',
        'proc_netsnmp_gauges': {
            'Ip': ['Forwarding', 'InReceives', 'InHdrErrors', 'InAddrErrors',
                   'ForwDatagrams', 'InUnknownProtos', 'InDiscards',
                   'InDelivers', 'OutRequests', 'OutDiscards',
                   'ReasmTimeout', 'ReasmReqds', 'ReasmOKs', 'ReasmFails',
                   'FragOKs', 'FragFails', 'FragCreates'],
            'Icmp': ['InMsgs', 'InErrors', 'InCsumErrors', 'InDestUnreachs',
                     'InTimeExcds', 'InParmProbs', 'InSrcQuenchs',
                     'InRedirects', 'InEchos', 'InEchoReps', 'OutMsgs',
                     'OutErrors', 'OutDestUnreachs', 'OutTimeExcds',
                     'OutParmProbs', 'OutSrcQuenchs', 'OutRedirects',
                     'OutEchos', 'OutEchoReps'],
            'IcmpMsg': ['OutType3'],
            'Tcp': ['MaxConn', 'ActiveOpens', 'PassiveOpens', 'AttemptFails',
                    'EstabResets', 'CurrEstab', 'InSegs', 'OutSegs',
                    'RetransSegs', 'InErrs', 'OutRsts', 'InCsumErrors'],
            'Udp': ['InDatagrams', 'NoPorts', 'InErrors', 'OutDatagrams',
                    'RcvbufErrors', 'SndbufErrors', 'InCsumErrors']
        },
        'proc_netsnmp_rates': {}
    }

    def __init__(self, log, config):
        """Plugin to measure various kernel metrics from /proc.

        :param log: A logger
        :type log: logging.RootLogger
        :param config: a plumd.config.Conf configuration helper instance.
        :type config: plumd.config.Conf
        """
        super(NetSnmp, self).__init__(log, config)
        self.config.defaults(NetSnmp.defaults)
        self.calc = Differential()
        self.proc_file = "{0}/net/snmp".format(config.get('proc_path'))
        self.filter = Filter()
        self.gauges = self.config.get('proc_netsnmp_gauges')
        self.rates = self.config.get('proc_netsnmp_rates')

    def poll(self):
        """Poll for kernel metrics under /proc.

        :rtype: ResultSet
        """
        return plumd.ResultSet(self.check())

    def check(self):
        """Return network protocol metrics from proc file net/snmp.

        Add entries to the configuration value 'skip_proc_net_snmp' to skip
        metrics.

        Add entries to the configuration value 'net_snmp_items' to match the
        format/order of the proc file net/snmp entries on the system.

        :rtype: plumd.Result
        """
        result = plumd.Result("netsnmp")

        # read the proc file
        dat = []
        with open(self.proc_file, 'r') as pfd:
            dat = pfd.read().strip().split("\n")

        # timestamp for Differential calculations
        times = time.time()

        # split values into lists
        dlist = deque([entry.split() for entry in dat])

        # put lists into key: value dict
        metrics = {}
        while dlist:
            headers = dlist.popleft()
            values = dlist.popleft()
            # { 'IpExt': {'InNoRoutes': 0, ...} } - [:-1] on IpExt: removes :
            metrics[headers[0][:-1]] = dict(zip(headers, values))

        # record gauges
        for proto, mnames in self.gauges.items():
            if proto not in metrics:
                self.log.warn("netsnmp: unknown protocol: {0}".format(proto))
                del self.gauges[proto]
                continue
            values = metrics[proto]
            for mname in mnames:
                if mname in values:
                    mstr = "{0}.{1}".format(proto, mname)
                    result.add(plumd.Int(mstr, values[mname]))
                else:
                    self.log.warn("netstat: unknown metric {0}".format(mname))
                    self.gauges[proto].remove(mname)
                    continue

        # record rates
        for proto, mnames in self.rates.items():
            if proto not in metrics:
                self.log.warn("netsnmp: unknown protocol: {0}".format(proto))
                del self.gauges[proto]
                continue
            values = metrics[proto]
            for mname in mnames:
                if mname in values:
                    mstr = "{0}.{1}".format(proto, mname)
                    mval = self.calc.per_second(mstr, int(values[mname]), times)
                    result.add(plumd.Int(mstr, mval))
                else:
                    self.log.warn("netstat: unknown metric {0}".format(mname))
                    self.rates[proto].remove(mname)
                    continue

        return [result]