Make possible to disable sending mentions to users

lib/AppConfig.php

@@ -225,6 +225,13 @@ class AppConfig {
      */
     private $_verification = "verify_peer_off";
 
+    /**
+     * The config for mentions
+     *
+     * @var string
+     */
+    private $_mentions = "mentions";
+
     /**
      * The config key for the secret key in jwt
      *
@@ -1153,6 +1160,16 @@ public function isUserAllowedToUse($userId = null) {
         return false;
     }
 
+    /**
+     * Check if sending mentions to users is enabled
+     *
+     * @return bool
+     */
+    public function isMentionsEnabled() {
+        $value = $this->config->getAppValue($this->appName, $this->_mentions, "true");
+        return in_array($value, ["on", "yes", "true"]);
+    }
+
     /**
      * Save the document service verification setting to the application configuration
      *

lib/Controller/EditorController.php

@@ -363,12 +363,15 @@ public function createNew($name, $dir, $templateId = null) {
     public function users($fileId, $operationType = null) {
         $this->logger->debug("Search users", ["app" => $this->appName]);
         $result = [];
-        $currentUserGroups = [];
 
         if (!$this->config->isUserAllowedToUse()) {
             return $result;
         }
 
+        if (!$this->config->isMentionsEnabled()) {
+            return $result;
+        }
+
         if (!$this->shareManager->allowEnumeration()) {
             return $result;
         }
@@ -505,6 +508,10 @@ public function mention($fileId, $anchor, $comment, $emails) {
             return ["error" => $this->trans->t("Not permitted")];
         }
 
+        if (!$this->config->isMentionsEnabled()) {
+            return ["error" => $this->trans->t("Mentions are not enabled")];
+        }
+
         if (empty($emails)) {
             return ["error" => $this->trans->t("Failed to send notification")];
         }