42 lines
1.5 KiB
JavaScript
42 lines
1.5 KiB
JavaScript
|
/*
|
||
|
|
Copyright 2018 Google LLC
|
||
|
|
|
||
|
|
Use of this source code is governed by an MIT-style
|
||
|
|
license that can be found in the LICENSE file or at
|
||
|
|
https://opensource.org/licenses/MIT.
|
||
|
|
*/
|
||
|
|
import { logger } from 'workbox-core/_private/logger.js';
|
||
|
|
import { isSupported } from './isSupported.js';
|
||
|
|
import './_version.js';
|
||
|
|
/**
|
||
|
|
* If the browser supports Navigation Preload, then this will enable it.
|
||
|
|
*
|
||
|
|
* @param {string} [headerValue] Optionally, allows developers to
|
||
|
|
* [override](https://developers.google.com/web/updates/2017/02/navigation-preload#changing_the_header)
|
||
|
|
* the value of the `Service-Worker-Navigation-Preload` header which will be
|
||
|
|
* sent to the server when making the navigation request.
|
||
|
|
*
|
||
|
|
* @memberof workbox-navigation-preload
|
||
|
|
*/
|
||
|
|
function enable(headerValue) {
|
||
|
|
if (isSupported()) {
|
||
|
|
self.addEventListener('activate', (event) => {
|
||
|
|
event.waitUntil(self.registration.navigationPreload.enable().then(() => {
|
||
|
|
// Defaults to Service-Worker-Navigation-Preload: true if not set.
|
||
|
|
if (headerValue) {
|
||
|
|
void self.registration.navigationPreload.setHeaderValue(headerValue);
|
||
|
|
}
|
||
|
|
if (process.env.NODE_ENV !== 'production') {
|
||
|
|
logger.log(`Navigation preload is enabled.`);
|
||
|
|
}
|
||
|
|
}));
|
||
|
|
});
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
if (process.env.NODE_ENV !== 'production') {
|
||
|
|
logger.log(`Navigation preload is not supported in this browser.`);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
export { enable };
|