Maintenance mode feature

app/controllers/redirect.php

@@ -4,7 +4,9 @@
 use Opencast\Models\VideosShares;
 use Opencast\Models\LTI\LtiHelper;
 use Opencast\Models\REST\ApiEventsClient;
+use Opencast\Models\REST\RestClient;
 use Opencast\Errors\Error;
+use Opencast\Errors\MaintenanceError;
 
 class RedirectController extends Opencast\Controller
 {
@@ -231,10 +233,13 @@ private function getLtiLinkFor($lti, $endpoint)
     }
 
     /**
-     * Load preview image from opencast and show it
+     * Serves a video preview image for the given video token.
      *
-     * @param String $episode_id
+     * Checks user permissions, fetches the preview image from Opencast if available,
+     * or falls back to a default image. Sets the appropriate content type header and outputs the image.
      *
+     * @param string $token The video token.
+     * @throws \Exception If access is denied.
      * @return void
      */
     public function preview_action($token)
@@ -247,17 +252,36 @@ public function preview_action($token)
             throw new \Exception('Access denied!');
         }
 
-        // get preview image
-        $api_events = ApiEventsClient::getInstance($video->config_id);
+        $plugin_path = $GLOBALS['ABSOLUTE_PATH_STUDIP'] . $this->plugin->getPluginPath();
+        $default_image_relative_path = '/assets/images/default-preview.png';
+        $image_default_url = URLHelper::getURL($this->plugin->getPluginUrl() . $default_image_relative_path);
+        $image_mimetype = mime_content_type($plugin_path . $default_image_relative_path);
+        $image_content = null;
+        if ($video->preview) {
+            $rest_client = null;
+            try {
+                $rest_client = ApiEventsClient::getInstance($video->config_id);
+            } catch (\Throwable $th) {
+                if ($th instanceof MaintenanceError) {
+                    $rest_client = RestClient::createReadOnlyInstance($video->config_id);
+                }
+            }
+
+            if (!empty($rest_client)) {
+                $response = $rest_client->fileRequest($video->preview);
+                $image_content = $response['body'] ?? null;
+                $image_mimetype = $response['mimetype'] ?? $image_mimetype;
+            }
+        }
 
-        $image = $video->preview ?
-            : URLHelper::getURL($this->plugin->getPluginUrl() . '/assets/images/default-preview.png');
+        if (empty($image_content)) {
+            $image_content = file_get_contents($image_default_url);
+        }
 
-        $response = $api_events->fileRequest($image);
+        header('Content-Type: '. $image_mimetype);
 
-        header('Content-Type: '. $response['mimetype'][0]);
+        echo $image_content;
 
-        echo $response['body'];
         die;
     }
 }

assets/css/opencast.scss

@@ -1477,4 +1477,18 @@ label.oc--file-upload {
     .oc--loading-indicator {
         left: 50%;
     }
-}
+}
+
+/* * * * * * * * * * * */
+/*     MESSAGE BOX     */
+/* * * * * * * * * * * */
+
+.messagebox {
+    .messagebox-html-container {
+        font-weight: 400 !important;
+        margin: 0px !important;
+        > p {
+            margin: 0px !important;
+        }
+    }
+}

cronjobs/opencast_clear_recycle_bin.php

@@ -46,8 +46,8 @@ public function execute($last_result, $parameters = array())
         foreach ($videos_by_config as $config_id => $videos) {
             echo 'Working on config with id #' . $config_id . "\n";
 
-            // Checking the connection.
-            if (!$this->isOpencastReachable($config_id)) {
+            // Checking the connection and maintenance status.
+            if (!$this->isOpencastReachable($config_id) || $this->isOpencastUnderMaintenance($config_id)) {
                 continue;
             }
 

cronjobs/opencast_discover_videos.php

@@ -51,7 +51,8 @@ public function execute($last_result, $parameters = array())
         foreach ($configs as $config) {
             echo 'Working on config with id #' . $config->id . "\n";
 
-            if (!$this->isOpencastReachable($config->id)) {
+            // Checking the connection and maintenance status.
+            if (!$this->isOpencastReachable($config->id) || $this->isOpencastUnderMaintenance($config->id)) {
                 continue;
             }
 

cronjobs/opencast_refresh_scheduling.php

@@ -55,7 +55,8 @@ public function execute($last_result, $parameters = array())
 
             echo 'Working on config with id #' . $config_id . "\n";
 
-            if (!$this->isOpencastReachable($config_id)) {
+            // Checking the connection and maintenance status.
+            if (!$this->isOpencastReachable($config_id) || $this->isOpencastUnderMaintenance($config_id)) {
                 continue;
             }
 

cronjobs/opencast_sync_acls.php

@@ -41,7 +41,8 @@ public function execute($last_result, $parameters = array())
         foreach ($configs as $config) {
             echo 'Working on config with id #' . $config->id . "\n";
 
-            if (!$this->isOpencastReachable($config->id)) {
+            // Checking the connection and maintenance status.
+            if (!$this->isOpencastReachable($config->id) || $this->isOpencastUnderMaintenance($config->id)) {
                 continue;
             }
 

cronjobs/opencast_sync_playlists.php

@@ -35,7 +35,8 @@ public function execute($last_result, $parameters = array())
         foreach ($configs as $config) {
             echo 'Working on config with id #' . $config->id . "\n";
 
-            if (!$this->isOpencastReachable($config->id)) {
+            // Checking the connection and maintenance status.
+            if (!$this->isOpencastReachable($config->id) || $this->isOpencastUnderMaintenance($config->id)) {
                 continue;
             }
 

lib/Errors/MaintenanceError.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Opencast\Errors;
+
+class MaintenanceError extends Error
+{
+    function __construct($message = null)
+    {
+        $message = $message ?? _('Opencast befindet sich derzeit in Wartung');
+        parent::__construct($message, 503);
+    }
+}

lib/Helpers/CronjobUtils/OpencastConnectionCheckerTrait.php

@@ -3,6 +3,7 @@
 namespace Opencast\Helpers\CronjobUtils;
 
 use Opencast\Models\REST\Config as OCConfig;
+use Opencast\Models\Config as ConfigModel;
 
 trait OpencastConnectionCheckerTrait
 {
@@ -11,6 +12,11 @@ trait OpencastConnectionCheckerTrait
      */
     private $not_reachable_message = 'Opencast is currently unreachable. Process postponed.';
 
+    /**
+     * @var string $not_reachable_message Message to display when Opencast is not reachable.
+     */
+    private $maintenance_message = 'Opencast is currently under maintenance. Process postponed.';
+
     /**
      * Checks if the Opencast instance is reachable for the given configuration ID.
      *
@@ -35,4 +41,26 @@ protected function isOpencastReachable(int $config_id, bool $check_engage_node =
         }
         return $is_opencast_reachable;
     }
+
+    /**
+     * Checks if the Opencast instance is under maintenance for the given configuration ID.
+     *
+     * This method checks if the Opencast instance is currently under maintenance.
+     * If it is, it prints a message and returns true. Otherwise, it returns false.
+     *
+     * @param int $config_id The ID of the Opencast configuration to check.
+     * @return bool True if Opencast is under maintenance, false otherwise.
+     */
+    protected function isOpencastUnderMaintenance(int $config_id)
+    {
+        $oc_config = ConfigModel::findOneBySql("id = ?", [$config_id]);
+        if ($oc_config) {
+            list($maintenance_active, $read_only) = $oc_config->isUnderMaintenance();
+            if ($maintenance_active) {
+                echo $this->maintenance_message . "\n";
+                return true;
+            }
+        }
+        return false;
+    }
 }

lib/Models/Config.php

@@ -16,6 +16,10 @@ class Config extends \SimpleOrMap
         'lti_consumerkey', 'lti_consumersecret', 'debug', 'ssl_ignore_cert_errors', 'episode_id_role_access'
     ];
 
+    const MAINTENANCE_MODE_OFF = 'off';
+    const MAINTENANCE_MODE_ON = 'on';
+    const MAINTENANCE_MODE_READONLY = 'read-only';
+
     protected static function configure($config = [])
     {
         $config['db_table'] = 'oc_config';
@@ -28,27 +32,62 @@ protected static function configure($config = [])
     }
 
     /**
-     * function getConfigForService  - retries configutation for a given REST-Service-Client
-     *
-     * @param string $service_type - client label
+     * Returns the merged configuration and endpoint data for a given service type and config ID.
      *
-     * @return array configuration for corresponding client
+     * Retrieves the Opencast configuration and endpoint for the specified service type and configuration ID,
+     * taking maintenance mode into account. Returns false if configuration or endpoint is missing,
+     * or null if access is not allowed due to maintenance restrictions.
      *
+     * @param string $service_type The type of Opencast service (e.g., 'ingest', 'search').
+     * @param int $config_id The configuration ID (default: 1).
+     * @return array|false|null Merged configuration and endpoint data, false if not found, or null if not accessible.
+     * @throws \Exception In case something goes wrong!
      */
     public static function getConfigForService($service_type, $config_id = 1)
     {
         if (isset($service_type)) {
-            $config = Endpoints::findOneBySQL(
+            $result = [];
+
+            $oc_config = self::find($config_id);
+            $endpoint_config = Endpoints::findOneBySQL(
                 'service_type = ? AND config_id = ?' ,
                 [$service_type, $config_id]
             );
 
-            if ($config) {
-                return $config->toArray() + self::find($config_id)->toArray();
-            } else {
+            if (empty($oc_config) || empty($endpoint_config)) {
                 return false;
             }
 
+            list($maintenance_on, $maintenance_readonly) = $oc_config->isUnderMaintenance();
+
+            $can_access = !$maintenance_on ||
+                ($maintenance_readonly && in_array($service_type, RESTConfig::ENGAGE_NODE_SERVICE_TYPES));
+
+            if (!$can_access) {
+                return null;
+            }
+
+            $oc_config_array = $oc_config->toArray();
+            $endpoint_config_array = $endpoint_config->toArray();
+
+            // Here we need to replace the service_url with the maintenance_engage_url_fallback (1. priority) if provided in config
+            // or the endpoint service_url (2. priority)
+            if ($maintenance_readonly) {
+                $replacing_server_url = $oc_config_array['maintenance_engage_url_fallback'];
+                if (empty($replacing_server_url)) {
+                    $replacing_server_url = $endpoint_config_array['service_url'];
+                }
+                $replacing_server_url_parsed = parse_url($replacing_server_url);
+
+                $replacing_server_url_clean = $replacing_server_url_parsed['scheme'] . '://'. $replacing_server_url_parsed['host']
+                    . (isset($replacing_server_url_parsed['port']) ? ':' . $replacing_server_url_parsed['port'] : '');
+
+                $oc_config_array['service_url'] = $replacing_server_url_clean;
+            }
+
+            $result = $endpoint_config_array + $oc_config_array;
+
+            return $result;
         } else {
             throw new \Exception(_("Es wurde kein Servicetyp angegeben."));
         }
@@ -163,6 +202,18 @@ public function updateSettings($json)
      */
     public function updateEndpoints()
     {
+
+        list($maintenance_on, $maintenance_readonly) = $this->isUnderMaintenance();
+
+        // Prevent updating endpoints if the server is under maintenance.
+        if ($maintenance_on) {
+            $message = [
+                'type' => 'warning',
+                'text' => _('Diese Opencast-Instanz ist derzeit im Wartungsmodus, daher können Endpunkte nicht aktualisiert werden.')
+            ];
+            return $message;
+        }
+
         $service_url =  parse_url($this->service_url);
 
         // check the selected url for validity
@@ -257,7 +308,7 @@ public function updateEndpoints()
                     }
 
                     // create new entries for workflow_config table
-                    WorkflowConfig::createAndUpdateByConfigId($this->id, $workflows);
+                    WorkflowConfig::createAndUpdateByConfigId($this->id);
 
                     $success_message[] = sprintf(
                         _('Die Opencast-Installation "%s" wurde erfolgreich konfiguriert.'),
@@ -282,4 +333,22 @@ public function updateEndpoints()
 
         return $message;
     }
+
+    /**
+     * Checks if the Opencast instance is in maintenance mode.
+     *
+     * @param bool $with_keys Whether to return an associative array with keys ('active', 'read_only').
+     * @return array [maintenance_on, maintenance_readonly] or ['active' => bool, 'read_only' => bool] if $with_keys is true.
+     */
+    public function isUnderMaintenance($with_keys = false)
+    {
+        $maintenance_on = ($this->maintenance_mode === self::MAINTENANCE_MODE_ON
+            || $this->maintenance_mode === self::MAINTENANCE_MODE_READONLY);
+
+        $res = [
+            'active' => $maintenance_on,
+            'read_only' => $this->maintenance_mode === self::MAINTENANCE_MODE_READONLY
+        ];
+        return $with_keys ? $res : array_values($res);
+    }
 }

lib/Models/LTI/LtiHelper.php

@@ -5,6 +5,7 @@
 use Opencast\Models\Config;
 use Opencast\Models\Endpoints;
 use Opencast\Providers\Perm;
+use Opencast\Models\REST\Config as RESTConfig;
 
 /**
  * LTI Helper class to create launch data
@@ -22,15 +23,27 @@ class LtiHelper
     public static function getLtiLinks($config_id)
     {
         $links = [];
-        $endpoints = Endpoints::findByConfig_id($config_id);
         $config    = Config::find($config_id);
 
+        list($maintenance_active, $read_only) = $config->isUnderMaintenance();
+
+        if ($maintenance_active && !$read_only) {
+            return [];
+        }
+
+        $endpoints = Endpoints::findByConfig_id($config_id);
+
         foreach ($endpoints as $endpoint) {
             // skip 'services' endpoints
             if ($endpoint->service_type == 'services') {
                 continue;
             }
 
+            // In read-only maintenance mode, we only allow engage node services!
+            if ($read_only && !in_array($endpoint->service_type, RESTConfig::ENGAGE_NODE_SERVICE_TYPES)) {
+                continue;
+            }
+
             $url = parse_url($endpoint['service_url']);
 
             $lti_url = $url['scheme'] . '://'. $url['host']

lib/Models/REST/ApiEventsClient.php

@@ -1,23 +1,19 @@
 <?php
 namespace Opencast\Models\REST;
 
-use Opencast\Models\Config;
 use Opencast\Models\Helpers;
 use Opencast\Models\Pager;
 
 class ApiEventsClient extends RestClient
 {
     public static $me;
-    public        $serviceName = 'ApiEvents';
 
     public function __construct($config_id = 1)
     {
-        if ($config = Config::getConfigForService('apievents', $config_id)) {
-            parent::__construct($config);
-        } else {
-            throw new \Exception ($this->serviceName . ': '
-                . _('Die Opencast-Konfiguration wurde nicht korrekt angegeben'));
-        }
+        $this->serviceName = 'ApiEvents';
+        $this->serviceType = 'apievents';
+        $config = $this->getConfigForClient($config_id);
+        parent::__construct($config);
     }
 
     /**