Autocheck for new DOMjudge releases

Discussed during the hackathon in 2023. We allow admins to toggle an
autoquery to domjudge.org for 2 reasons:
- Alerting users that a new version might exist, helping us in case of
  security releases.
- Giving a gentle nudge for people to upgrade making support easier.
- Getting some information on what installations are out there.

Author: vmcj

etc/db-config.yaml

@@ -392,6 +392,11 @@
             description: Time in seconds after an external contest source reader last checked in before showing its status as `critical`.
             regex: /^\d+$/
             error_message: A non-negative number is required.
+        -   name: check_new_version
+            type: bool
+            default_value: false
+            public: false
+            description: Automatically check for new DOMjudge release?
         -   name: adminer_enabled
             type: bool
             default_value: false

webapp/composer.json

@@ -111,7 +111,8 @@
 		"twig/extra-bundle": "^3.5",
 		"twig/markdown-extra": "^3.5",
 		"twig/string-extra": "^3.5",
-		"twig/twig": "^3.6"
+		"twig/twig": "^3.6",
+		"z4kn4fein/php-semver": "^3.0"
 	},
 	"require-dev": {
 		"ext-dom": "*",

webapp/composer.lock

@@ -38,6 +38,7 @@
 use Doctrine\ORM\NoResultException;
 use Doctrine\ORM\Query\Expr\Join;
 use Doctrine\ORM\QueryBuilder;
+use Exception;
 use InvalidArgumentException;
 use Psr\Log\LoggerInterface;
 use ReflectionClass;
@@ -63,6 +64,7 @@
 use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;
 use Symfony\Component\Security\Core\User\UserInterface;
 use Twig\Environment;
+use z4kn4fein\SemVer\Version;
 use ZipArchive;
 
 class DOMJudgeService
@@ -1671,4 +1673,59 @@ public function getAllowedLanguagesForContest(?Contest $contest) : array {
             ->getQuery()
             ->getResult();
     }
+
+    public function checkNewVersion(): string|false {
+        if (!$this->config->get('check_new_version')) {
+            return false;
+        }
+        $versionLocalString = explode("/", str_replace("DEV", "-prerelease", DOMJUDGE_VERSION))[0];
+        $versionLocal = Version::parse($versionLocalString, false);
+        $versionUrl = 'https://versions.domjudge.org';
+        $options = ['http' => ['method' => 'GET', 'header' => "User-Agent: tarball/" . $versionLocalString . "\r\n"]];
+        $context = stream_context_create($options);
+        $response = @file_get_contents($versionUrl, false, $context);
+	if ($response === false) {
+            return false;
+        }
+        $versions = json_decode($response, true);
+        /* Steer towards to the latest patch first 
+         * the user can see on the website if there is a new Major/minor themselves
+         * otherwise the latest minor, or Major release. So the user might make the upgrade path:
+         * DJ6.0.0 -> DJ6.0.6 -> DJ6.6.0 -> DJ9.0.0 instead of
+         *         -> DJ6.0.[1..6] -> DJ6.[1..6] -> DJ[7..9].0.0
+         */
+        $latestPatchString = $versionLocal;
+        if (isset($versions[$versionLocal->getMajor()][$versionLocal->getMinor()])) {
+            $latestPatchString = Version::rsortString($versions[$versionLocal->getMajor()][$versionLocal->getMinor()])[0];
+            $latestPatch = Version::parse($latestPatchString);
+            if (Version::compare($versionLocal, $latestPatch) < 0) {
+                return $latestPatchString;
+            }
+        }
+        $latestMinorString = $versionLocal;
+        if (isset($versions[$versionLocal->getMajor()])) {
+            $highestMinorInMajor = array_keys($versions[$versionLocal->getMajor()]);
+            rsort($highestMinorInMajor);
+            $latestMinorString = Version::rsortString($versions[$versionLocal->getMajor()][$highestMinorInMajor[0]])[0];
+            $latestMinor = Version::parse($latestMinorString);
+            if (Version::compare($versionLocal, $latestMinor) < 0) {
+                return $latestMinorString;
+            }
+        }
+        $latestMajorString = $versionLocal;
+        try {
+            $highestMajor = array_keys($versions);
+            rsort($highestMajor);
+            $highestMinorInMajor = array_keys($versions[$highestMajor[0]]);
+            rsort($highestMinorInMajor);
+            $latestMajorString = Version::rsortString($versions[$highestMajor[0]][$highestMinorInMajor[0]])[0];
+            $latestMajor = Version::parse($latestMajorString);
+            if (Version::compare($versionLocal, $latestMajor) < 0) {
+                return $latestMajorString;
+            }
+        } catch (Exception $e) {
+            return false;
+        }
+        return false;
+    }
 }

webapp/src/Service/DOMJudgeService.php

@@ -159,6 +159,7 @@ public function getGlobals(): array
             'doc_links'                     => $this->dj->getDocLinks(),
             'allow_registration'            => $selfRegistrationCategoriesCount !== 0,
             'enable_ranking'                => $this->config->get('enable_ranking'),
+            'new_version_available'         => $this->dj->checkNewVersion(),
             'editor_themes'                 => [
                 'vs'                        => ['name' => 'Visual Studio (light)'],
                 'vs-dark'                   => ['name' => 'Visual Studio (dark)'],

webapp/src/Twig/TwigExtension.php

@@ -93,6 +93,13 @@
                 </li>
             </ul>
         {% endif %}
+        {% if new_version_available %}
+            <ul class="navbar-nav">
+                <li class="nav-item nav-link">
+                    <i class="fa-solid fa-ship fa-2x"></i> New release {{ new_version_available }} available.
+                </li>
+            </ul>
+        {% endif %}
 
         <ul class="navbar-nav ml-auto">