create subscription document that is subscribed to by default when the page is created

packages/app/src/server/routes/apiv3/pages.js

@@ -1,6 +1,8 @@
 import { pagePathUtils } from '@growi/core';
 import loggerFactory from '~/utils/logger';
 
+import Subscription, { STATUS_SUBSCRIBE } from '~/server/models/subscription';
+
 const logger = loggerFactory('growi:routes:apiv3:pages'); // eslint-disable-line no-unused-vars
 const express = require('express');
 const pathUtils = require('growi-commons').pathUtils;
@@ -316,6 +318,13 @@ module.exports = (crowi) => {
       }
     }
 
+    try {
+      await Subscription.subscribeByPageId(req.user._id, createdPage._id, STATUS_SUBSCRIBE);
+    }
+    catch (err) {
+      logger.error('Failed to update subscribe status', err);
+    }
+
     return res.apiv3(result, 201);
   });