unbrake-frontend/src/serviceWorker.js
/*
* This optional code is used to register a service worker.
* register() is not called by default.
*/
/*
* 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 subsequent visits to a page, after all the
* existing tabs open on the page have been closed, since previously cached
* resources are updated in the background.
*/
/*
* To learn more about the benefits of this model and instructions on how to
* opt-in, read https://bit.ly/CRA-PWA
*/
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}$/
)
);
function registerValidSW(swUrl, config) {
navigator.serviceWorker
.register(swUrl)
.then(registration => {
// eslint-disable-next-line no-param-reassign
registration.onupdatefound = () => {
const installingWorker = registration.installing;
if (installingWorker === null) {
return;
}
installingWorker.onstatechange = () => {
if (installingWorker.state === "installed") {
if (navigator.serviceWorker.controller) {
/*
* At this point, the updated precached content has been fetched,
* but the previous service worker will still serve the older
* content until all client tabs are closed.
* console.log(
* "New content is available and will be used when all " +
* "tabs for this page are closed. See https://bit.ly/CRA-PWA."
* );
*/
// Execute callback
if (config && config.onUpdate) {
config.onUpdate(registration);
}
} else if (config && config.onSuccess) {
/*
* 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.");
*/
// Execute callback
config.onSuccess(registration);
} 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, config) {
// 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.
const contentType = response.headers.get("content-type");
const notFoundHttpStatus = 404;
const notFoundInArray = -1;
if (
response.status === notFoundHttpStatus ||
(contentType !== null &&
contentType.indexOf("javascript") === notFoundInArray)
) {
// 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, config);
}
})
.catch(() => {
/*
* console.log(
* "No internet connection found. App is running in offline mode."
* );
*/
});
}
export function register(config) {
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.href);
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/facebook/create-react-app/issues/2374
*/
return;
}
window.addEventListener("load", () => {
const swUrl = `${process.env.PUBLIC_URL}/service-worker.js`;
if (isLocalhost) {
// This is running on localhost. Let"s check if a service worker still exists or not.
checkValidServiceWorker(swUrl, config);
/*
* Add some additional logging to localhost, pointing developers to the
* service worker/PWA documentation.
*/
navigator.serviceWorker.ready.then(() => {
/*
* console.log(
* "This web app is being served cache-first by a service " +
* "worker. To learn more, visit https://bit.ly/CRA-PWA"
* );
*/
});
} else {
// Is not localhost. Just register service worker
registerValidSW(swUrl, config);
}
});
}
}
export function unregister() {
if ("serviceWorker" in navigator) {
navigator.serviceWorker.ready.then(registration => {
registration.unregister();
});
}
}