Nextcloud update check for Check_MK

check_nextcloud_update.php

#! /usr/bin/env php
<?php
/**
 * This is a simple local check for Check_MK which triggers a warning in case an update for your Nextcloud installation is available.
 *
 * The check does not request the update information from the Nextcloud update server, the cached data stored in the database is used instead.
 *
 * The check was tested with Nextcloud 12. As this script is not using some official API of Nextcloud, a future update of Nextcloud might break it.
 *
 * Installation:
 * 1. Specify the location to your Nextcloud installation in the $baseDir$ variable
 * 2. Save the script in the local checks folder of the Check_MK Agent (e.g. /usr/lib/check_mk_agent/local/check_nextcloud_update.php)
 * 3. Make it executable (chmod +x /usr/lib/check_mk_agent/local/check_nextcloud_update.php)
 */

$baseDir = "/var/www/nextcloud";// Specify the path to your Nextcloud installation

function getNewVersion($baseDir)
{
    require $baseDir . "/config/config.php";

    $pdo = new PDO(sprintf("mysql:host=%s;dbname=%s", $CONFIG["dbhost"], $CONFIG["dbname"]), $CONFIG["dbuser"], $CONFIG["dbpassword"]);

    $query = $pdo->query("
        SELECT `configvalue`
        FROM `oc_appconfig`
        WHERE `appid` = 'core' AND `configkey` = 'lastupdateResult'
    ");

    if (!$query->rowCount()) {
        return null;
    }

    $json = json_decode($query->fetchObject()->configvalue, true);

    if ($json === null) {
        return null;
    }

    if (!is_array($json)) {
        return null;
    }

    if (empty($json)) {
        return true;
    }

    if (!isset($json["version"])) {
        return null;
    }

    if (!is_string($json["version"])) {
        return null;
    }

    return $json["version"];
}

function getCurrentVersion($baseDir)
{
    require $baseDir . "/version.php";

    return implode(".", $OC_Version);
}

function output($state, $message)
{
    printf("%d Nextcloud_Version - %s\n", $state, $message);
}

$newVersion = getNewVersion($baseDir);
$currentVersion = getCurrentVersion($baseDir);

if ($newVersion === null) {
    output(1, "Unable to read new version");
} elseif (!is_string($currentVersion)) {
    output(1, "Unable to read current version");
} elseif ($newVersion === true or $newVersion === $currentVersion) {
    output(0, sprintf("No update available (installed version: %s)", $currentVersion));
} else {
    output(1, sprintf("An update to version %s is available (installed version: %s)", $newVersion, $currentVersion));
}