agents/plugins/apache_status

   1 #!/usr/bin/python
   2 # -*- encoding: utf-8; py-indent-offset: 4 -*-
   3 # +------------------------------------------------------------------+
   4 # |             ____ _               _        __  __ _  __           |
   5 # |            / ___| |__   ___  ___| | __   |  \/  | |/ /           |
   6 # |           | |   | '_ \ / _ \/ __| |/ /   | |\/| | ' /            |
   7 # |           | |___| | | |  __/ (__|   <    | |  | | . \            |
   8 # |            \____|_| |_|\___|\___|_|\_\___|_|  |_|_|\_\           |
   9 # |                                                                  |
  10 # | Copyright Mathias Kettner 2014             mk@mathias-kettner.de |
  11 # +------------------------------------------------------------------+
  12 #
  13 # This file is part of Check_MK.
  14 # The official homepage is at http://mathias-kettner.de/check_mk.
  15 #
  16 # check_mk is free software;  you can redistribute it and/or modify it
  17 # under the  terms of the  GNU General Public License  as published by
  18 # the Free Software Foundation in version 2.  check_mk is  distributed
  19 # in the hope that it will be useful, but WITHOUT ANY WARRANTY;  with-
  20 # out even the implied warranty of  MERCHANTABILITY  or  FITNESS FOR A
  21 # PARTICULAR PURPOSE. See the  GNU General Public License for more de-
  22 # tails. You should have  received  a copy of the  GNU  General Public
  23 # License along with GNU Make; see the file  COPYING.  If  not,  write
  24 # to the Free Software Foundation, Inc., 51 Franklin St,  Fifth Floor,
  25 # Boston, MA 02110-1301 USA.
  26
  27 # Check_MK-Agent-Plugin - Apache Server Status
  28 #
  29 # Fetches the server-status page from detected or configured apache
  30 # processes to gather status information about this apache process.
  31 #
  32 # To make this agent plugin work you have to load the status_module
  33 # into your apache process. It is also needed to enable the "server-status"
  34 # handler below the URL "/server-status".
  35 #
  36 # By default this plugin tries to detect all locally running apache processes
  37 # and to monitor them. If this is not good for your environment you might
  38 # create an apache_status.cfg file in MK_CONFDIR and populate the servers
  39 # list to prevent executing the detection mechanism.
  40 #
  41 # It is also possible to override or extend the ssl_ports variable to make the
  42 # check contact other ports than 443 with HTTPS requests.
  43
  44 import os
  45 import re
  46 import socket
  47 import sys
  48 import urllib2
  49 import ssl
  50
  51 config_dir = os.getenv("MK_CONFDIR", "/etc/check_mk")
  52 config_file = config_dir + "/apache_status.conf"
  53
  54 if not os.path.exists(config_file):
  55     config_file = config_dir + "/apache_status.cfg"
  56
  57 # We have to deal with socket timeouts. Python > 2.6
  58 # supports timeout parameter for the urllib2.urlopen method
  59 # but we are on a python 2.5 system here which seem to use the
  60 # default socket timeout. We are local here so  set it to 1 second.
  61 socket.setdefaulttimeout(5.0)
  62
  63 # None or list of (proto, ipaddress, port) tuples.
  64 # proto is 'http' or 'https'
  65 servers = None
  66 ssl_ports = [443]
  67
  68 if os.path.exists(config_file):
  69     execfile(config_file)
  70
  71
  72 def try_detect_servers():
  73     results = []
  74
  75     for netstat_line in os.popen('netstat -tlnp 2>/dev/null').readlines():
  76         parts = netstat_line.split()
  77         # Skip lines with wrong format
  78         if len(parts) < 7 or '/' not in parts[6]:
  79             continue
  80
  81         pid, proc = parts[6].split('/', 1)
  82         to_replace = re.compile('^.*/')
  83         proc = to_replace.sub('', proc)
  84
  85         procs = ['apache2', 'httpd', 'httpd2-prefork', 'httpd2-worker', 'httpd.worker', 'fcgi-pm']
  86         # the pid/proc field length is limited to 19 chars. Thus in case of
  87         # long PIDs, the process names are stripped of by that length.
  88         # Workaround this problem here
  89         procs = [p[:19 - len(pid) - 1] for p in procs]
  90
  91         # Skip unwanted processes
  92         if proc not in procs:
  93             continue
  94
  95         server_address, server_port = parts[3].rsplit(':', 1)
  96         server_port = int(server_port)
  97
  98         # Use localhost when listening globally
  99         if server_address == '0.0.0.0':
 100             server_address = '127.0.0.1'
 101         elif server_address == '::':
 102             server_address = '[::1]'
 103         elif ':' in server_address:
 104             server_address = '[%s]' % server_address
 105
 106         # Switch protocol if port is SSL port. In case you use SSL on another
 107         # port you would have to change/extend the ssl_port list
 108         if server_port in ssl_ports:
 109             scheme = 'https'
 110         else:
 111             scheme = 'http'
 112
 113         results.append((scheme, server_address, server_port))
 114
 115     return results
 116
 117
 118 if servers is None:
 119     servers = try_detect_servers()
 120
 121 if not servers:
 122     sys.exit(0)
 123
 124 sys.stdout.write('<<<apache_status>>>\n')
 125 for server in servers:
 126     if isinstance(server, tuple):
 127         proto, address, port = server
 128         page = 'server-status'
 129     else:
 130         proto = server['protocol']
 131         address = server['address']
 132         port = server['port']
 133         page = server.get('page', 'server-status')
 134
 135     portspec = ':%d' % port if port else ''
 136
 137     try:
 138         url = '%s://%s%s/%s?auto' % (proto, address, portspec, page)
 139         # Try to fetch the status page for each server
 140         try:
 141             request = urllib2.Request(url, headers={"Accept": "text/plain"})
 142             fd = urllib2.urlopen(request)
 143         except urllib2.URLError, e:
 144             if 'unknown protocol' in str(e):
 145                 # HACK: workaround misconfigurations where port 443 is used for
 146                 # serving non ssl secured http
 147                 url = 'http://%s%s/server-status?auto' % (address, portspec)
 148                 fd = urllib2.urlopen(url)
 149             else:
 150                 raise
 151         except Exception, e:
 152             if 'doesn\'t match' in str(e) and address in ("127.0.0.1", "[::1]", "localhost"):
 153                 # HACK: workaround if SSL port is found and localhost is using
 154                 # SSL connections but certificate does not match
 155                 no_cert_context = ssl.create_default_context()
 156                 no_cert_context.check_hostname = False
 157                 no_cert_context.verify_mode = ssl.CERT_NONE
 158                 fd = urllib2.urlopen(url, context=no_cert_context)
 159             else:
 160                 raise
 161
 162         for line in fd.read().split('\n'):
 163             if not line.strip():
 164                 continue
 165             if line.lstrip()[0] == '<':
 166                 # Seems to be html output. Skip this server.
 167                 break
 168
 169             sys.stdout.write("%s %s %s\n" % (address, port, line))
 170     except urllib2.HTTPError, e:
 171         sys.stderr.write('HTTP-Error (%s%s): %s %s\n' % (address, portspec, e.code, e))
 172
 173     except Exception, e:
 174         sys.stderr.write('Exception (%s%s): %s\n' % (address, portspec, e))