next-csrf
Version:
CSRF mitigation library for Next.js
39 lines (38 loc) • 1.38 kB
JavaScript
/*
* Copyright 2020 Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
let isUnloading = false;
let listenersAdded = false;
const onPageHide = (event) => {
isUnloading = !event.persisted;
};
const addListeners = () => {
addEventListener('pagehide', onPageHide);
// Unload is needed to fix this bug:
// https://bugs.chromium.org/p/chromium/issues/detail?id=987409
// eslint-disable-next-line @typescript-eslint/no-empty-function
addEventListener('unload', () => { });
};
export const onHidden = (cb, once = false) => {
if (!listenersAdded) {
addListeners();
listenersAdded = true;
}
addEventListener('visibilitychange', ({ timeStamp }) => {
if (document.visibilityState === 'hidden') {
cb({ timeStamp, isUnloading });
}
}, { capture: true, once });
};