Munin contributed plugins

#!/usr/bin/python3

"""

=head1 NAME

monit_parser -  Monit status parser plugin for munin.

=head1 APPLICABLE SYSTEMS

Any system being able to query monit servers via http.

Monit needs to be configured with the httpd port enabled, e.g.:

    set httpd port 2812

Optionally monit authentication can be configured, e.g.:

    set httpd port 2812

      allow munin:s3cr3t read-only

=head1 CONFIGURATION

By default the monit instance at localhost is queried:

  [monit_parser]

  env.port 2812

  env.host localhost

Optionally monit authentication can be configured, e.g.:

  [monit_parser]

  env.username munin

  env.password s3cr3t

=head1 AUTHOR

  Todd Troxell <ttroxell@debian.org>

  Lars Kruse <devel@sumpfralle.de>

=head1 MAGIC MARKERS

  family=auto

  capabilities=autoconf

=cut

"""

import xml.dom.minidom

import os

import sys

import urllib.request

import base64

MONIT_XML_URL = ("http://{host}:{port}/_status?format=xml"

                 .format(host=os.getenv("host", "localhost"),

                         port=os.getenv("port", "2812")))

def sanitize(s):

    OK_CHARS = "abcdefghijklmnopqrstuvwxyz0123456789"

    return "".join([char for char in s if char in OK_CHARS])

def get_monit_status_xml():

    try:

        req = urllib.request.Request(url=MONIT_XML_URL)

        if os.getenv("password"):

            auth_str = "%s:%s" % (os.getenv("username"), os.getenv("password"))

            auth_bytes = bytes(auth_str, "utf-8")

            auth_base64_bytes = base64.b64encode(auth_bytes)

            auth_base64_str = str(auth_base64_bytes, "ascii")

            auth_value = "Basic %s" % auth_base64_str

            req.add_header("Authorization", auth_value)

        conn = urllib.request.urlopen(req)

    except urllib.error.URLError as exc:

        conn = None

    if conn is None:

        raise RuntimeError("Failed to open monit status URL: {}".format(MONIT_XML_URL))

    else:

        return xml.dom.minidom.parse(conn)

def parse_processes():

    dom = get_monit_status_xml()

    procs = {}

    for item in dom.getElementsByTagName("service"):

        if item.getAttribute("type") == "3":

            # daemon with memory usage and CPU

            name = item.getElementsByTagName("name")[0].childNodes[0].data

            memory_usage = item.getElementsByTagName("memory")[0].getElementsByTagName(

                "kilobytetotal")[0].childNodes[0].data

            cpu_usage = item.getElementsByTagName("cpu")[0].getElementsByTagName(

                "percenttotal")[0].childNodes[0].data

            procs[name] = {}

            procs[name]["total_memory"] = memory_usage

            procs[name]["total_cpu"] = cpu_usage

    return procs

action = sys.argv[1] if (len(sys.argv) > 1) else None

if action == 'autoconf':

    try:

        get_monit_status_xml()

        print("yes")

    except RuntimeError:

        print("no (failed to request monit status)")

elif action == 'config':

    procs = parse_processes()

    print('graph_title Per process stats from Monit')

    print('graph_vlabel usage of memory [kB] or cpu [%]')

    print('graph_category munin')

    for process in procs:

        for stat in procs[process]:

            print("monit_%s_%s.label %s.%s" % (sanitize(process), stat, process, stat))

            if stat == 'total_memory':

                # the allocated memory may never be zero

                print("monit_%s_%s.warning 1:" % (sanitize(process), stat))

else:

    for process, stats in parse_processes().items():

        for stat_key, stat_value in stats.items():

            print("monit_%s_%s.value %s" % (sanitize(process), stat_key, stat_value))