/*------------------------------------------------------------------------------- | |
* Copyright (C) 2017 ANSYS medini Technologies AG | |
* | |
* This program and the accompanying materials are made | |
* available under the terms of the Eclipse Public License 2.0 | |
* which is available at https://www.eclipse.org/legal/epl-2.0/ | |
* | |
* SPDX-License-Identifier: EPL-2.0 | |
* | |
* Contributors: | |
* ANSYS medini Technologies AG - initial API and implementation | |
*------------------------------------------------------------------------------*/ | |
// In production, we register a service worker to serve assets from local cache. | |
// This lets the app load faster on subsequent visits in production, and gives | |
// it offline capabilities. However, it also means that developers (and users) | |
// will only see deployed updates on the "N+1" visit to a page, since previously | |
// cached resources are updated in the background. | |
// To learn more about the benefits of this model, read https://goo.gl/KwvDNy. | |
// This link also includes instructions on opting out of this behavior. | |
const isLocalhost = Boolean( | |
window.location.hostname === 'localhost' || | |
// [::1] is the IPv6 localhost address. | |
window.location.hostname === '[::1]' || | |
// 127.0.0.1/8 is considered localhost for IPv4. | |
window.location.hostname.match( | |
/^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/ | |
) | |
); | |
export default function register() { | |
if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) { | |
// The URL constructor is available in all browsers that support SW. | |
const publicUrl = new URL(process.env.PUBLIC_URL, window.location); | |
if (publicUrl.origin !== window.location.origin) { | |
// Our service worker won't work if PUBLIC_URL is on a different origin | |
// from what our page is served on. This might happen if a CDN is used to | |
// serve assets; see https://github.com/facebookincubator/create-react-app/issues/2374 | |
return; | |
} | |
window.addEventListener('load', () => { | |
const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`; | |
if (!isLocalhost) { | |
// Is not local host. Just register service worker | |
registerValidSW(swUrl); | |
} else { | |
// This is running on localhost. Lets check if a service worker still exists or not. | |
checkValidServiceWorker(swUrl); | |
} | |
}); | |
} | |
} | |
function registerValidSW(swUrl) { | |
navigator.serviceWorker | |
.register(swUrl) | |
.then(registration => { | |
registration.onupdatefound = () => { | |
const installingWorker = registration.installing; | |
installingWorker.onstatechange = () => { | |
if (installingWorker.state === 'installed') { | |
if (navigator.serviceWorker.controller) { | |
// At this point, the old content will have been purged and | |
// the fresh content will have been added to the cache. | |
// It's the perfect time to display a "New content is | |
// available; please refresh." message in your web app. | |
console.log('New content is available; please refresh.'); | |
} else { | |
// At this point, everything has been precached. | |
// It's the perfect time to display a | |
// "Content is cached for offline use." message. | |
console.log('Content is cached for offline use.'); | |
} | |
} | |
}; | |
}; | |
}) | |
.catch(error => { | |
console.error('Error during service worker registration:', error); | |
}); | |
} | |
function checkValidServiceWorker(swUrl) { | |
// Check if the service worker can be found. If it can't reload the page. | |
fetch(swUrl) | |
.then(response => { | |
// Ensure service worker exists, and that we really are getting a JS file. | |
if ( | |
response.status === 404 || | |
response.headers.get('content-type').indexOf('javascript') === -1 | |
) { | |
// No service worker found. Probably a different app. Reload the page. | |
navigator.serviceWorker.ready.then(registration => { | |
registration.unregister().then(() => { | |
window.location.reload(); | |
}); | |
}); | |
} else { | |
// Service worker found. Proceed as normal. | |
registerValidSW(swUrl); | |
} | |
}) | |
.catch(() => { | |
console.log( | |
'No internet connection found. App is running in offline mode.' | |
); | |
}); | |
} | |
export function unregister() { | |
if ('serviceWorker' in navigator) { | |
navigator.serviceWorker.ready.then(registration => { | |
registration.unregister(); | |
}); | |
} | |
} |