check_mediawiki_version.py

#! /usr/bin/python3
#
# Icinga plugin for monitoring MediaWiki versions.
#
# Copy this file into /usr/local/lib/nagios/plugins/
#
# Usage: check_mediawiki_version.py <url_of_wiki>
#

import re
import sys

from lxml import etree
import requests

USER_AGENT = "check_mediawiki_version.py/0.0.1 Icinga Plugin"
URL_MW_DOWNLOAD = "https://www.mediawiki.org/wiki/Download"

parser = etree.HTMLParser()
headers = {"user-agent": USER_AGENT}

try:
    # Scrape the monitored mediawiki site. Look for:
    # <meta name="generator" content="MediaWiki 1.26.2" />

    current_version = None

    r = requests.get(sys.argv[1], headers=headers)
    r.raise_for_status()

    root = etree.fromstring(r.content, parser)
    for e in root.xpath('//meta[@name="generator"]'):
        m = re.match(r"^MediaWiki (\d+\.\d+\.\d+)$", e.get("content"))
        if m:
            current_version = m.group(1).split(".")
            break

    if current_version is None:
        raise Exception('<meta name="generator"> not found')

    # print (current_version)

    # Next scrape the mediawiki foundation download site.  Look for:
    # <a href="//releases.wikimedia.org/mediawiki/1.27/mediawiki-1.27.3.tar.gz">download</a>

    supported_versions = []

    r = requests.get(URL_MW_DOWNLOAD, headers=headers)
    r.raise_for_status()

    root = etree.fromstring(r.content, parser)
    for e in root.xpath(
        '//table//a[starts-with (@href, "//releases.wikimedia.org/mediawiki/")]'
    ):
        m = re.search("\d+\.\d+\.\d+", e.get("href"))
        if m:
            supported_versions.append(m.group(0).split("."))

    # print (supported_versions)

    # check if the monitored site is still supported
    # and exit accordingly

    if current_version in supported_versions:
        print("MEDIAWIKI OK - Version: %s" % ".".join(current_version))
        sys.exit(0)

    upgrade_paths = [
        ".".join(v) for v in sorted(supported_versions) if v > current_version
    ]
    # print (upgrade_paths)

    print(
        "MEDIAWIKI CRITICAL - Version: %s, Supported versions: %s"
        % (".".join(current_version), ", ".join(upgrade_paths))
    )
    sys.exit(2)

except Exception as exc:
    print("MEDIAWIKI UNKNOWN: %s" % str(exc))
    sys.exit(3)