impl checking token existence

src/server/routes/apiv3/slack-integration-settings.js

@@ -112,7 +112,11 @@ module.exports = (crowi) => {
     // retrieve connection statuses
     let connectionStatuses;
     if (currentBotType === 'customBotWithoutProxy') {
-      connectionStatuses = Object.fromEntries(await getConnectionStatuses([settings.slackBotToken]));
+      const token = settings.slackBotToken;
+      // check the token is not null
+      if (token != null) {
+        connectionStatuses = Object.fromEntries(await getConnectionStatuses([]));
+      }
     }
     else {
       // connectionStatuses = getConnectionStatusesFromProxy();