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/*
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 { assert } from 'workbox-core/_private/assert.js';
import { timeout } from 'workbox-core/_private/timeout.js';
import { resultingClientExists } from 'workbox-core/_private/resultingClientExists.js';
import { logger } from 'workbox-core/_private/logger.js';
import { responsesAreSame } from './responsesAreSame.js';
import { CACHE_UPDATED_MESSAGE_META, CACHE_UPDATED_MESSAGE_TYPE, DEFAULT_HEADERS_TO_CHECK, NOTIFY_ALL_CLIENTS, } from './utils/constants.js';
import './_version.js';
// UA-sniff Safari: https://stackoverflow.com/questions/7944460/detect-safari-browser
// TODO(philipwalton): remove once this Safari bug fix has been released.
// https://bugs.webkit.org/show_bug.cgi?id=201169
const isSafari = /^((?!chrome|android).)*safari/i.test(navigator.userAgent);
/**
* Generates the default payload used in update messages. By default the
* payload includes the `cacheName` and `updatedURL` fields.
*
* @return Object
* @private
*/
function defaultPayloadGenerator(data) {
return {
cacheName: data.cacheName,
updatedURL: data.request.url,
};
}
/**
* Uses the `postMessage()` API to inform any open windows/tabs when a cached
* response has been updated.
*
* For efficiency's sake, the underlying response bodies are not compared;
* only specific response headers are checked.
*
* @memberof workbox-broadcast-update
*/
class BroadcastCacheUpdate {
/**
* Construct a BroadcastCacheUpdate instance with a specific `channelName` to
* broadcast messages on
*
* @param {Object} [options]
* @param {Array<string>} [options.headersToCheck=['content-length', 'etag', 'last-modified']]
* A list of headers that will be used to determine whether the responses
* differ.
* @param {string} [options.generatePayload] A function whose return value
* will be used as the `payload` field in any cache update messages sent
* to the window clients.
* @param {boolean} [options.notifyAllClients=true] If true (the default) then
* all open clients will receive a message. If false, then only the client
* that make the original request will be notified of the update.
*/
constructor({ generatePayload, headersToCheck, notifyAllClients, } = {}) {
this._headersToCheck = headersToCheck || DEFAULT_HEADERS_TO_CHECK;
this._generatePayload = generatePayload || defaultPayloadGenerator;
this._notifyAllClients = notifyAllClients !== null && notifyAllClients !== void 0 ? notifyAllClients : NOTIFY_ALL_CLIENTS;
}
/**
* Compares two [Responses](https://developer.mozilla.org/en-US/docs/Web/API/Response)
* and sends a message (via `postMessage()`) to all window clients if the
* responses differ. Neither of the Responses can be
* [opaque](https://developer.chrome.com/docs/workbox/caching-resources-during-runtime/#opaque-responses).
*
* The message that's posted has the following format (where `payload` can
* be customized via the `generatePayload` option the instance is created
* with):
*
* ```
* {
* type: 'CACHE_UPDATED',
* meta: 'workbox-broadcast-update',
* payload: {
* cacheName: 'the-cache-name',
* updatedURL: 'https://example.com/'
* }
* }
* ```
*
* @param {Object} options
* @param {Response} [options.oldResponse] Cached response to compare.
* @param {Response} options.newResponse Possibly updated response to compare.
* @param {Request} options.request The request.
* @param {string} options.cacheName Name of the cache the responses belong
* to. This is included in the broadcast message.
* @param {Event} options.event event The event that triggered
* this possible cache update.
* @return {Promise} Resolves once the update is sent.
*/
async notifyIfUpdated(options) {
if (process.env.NODE_ENV !== 'production') {
assert.isType(options.cacheName, 'string', {
moduleName: 'workbox-broadcast-update',
className: 'BroadcastCacheUpdate',
funcName: 'notifyIfUpdated',
paramName: 'cacheName',
});
assert.isInstance(options.newResponse, Response, {
moduleName: 'workbox-broadcast-update',
className: 'BroadcastCacheUpdate',
funcName: 'notifyIfUpdated',
paramName: 'newResponse',
});
assert.isInstance(options.request, Request, {
moduleName: 'workbox-broadcast-update',
className: 'BroadcastCacheUpdate',
funcName: 'notifyIfUpdated',
paramName: 'request',
});
}
// Without two responses there is nothing to compare.
if (!options.oldResponse) {
return;
}
if (!responsesAreSame(options.oldResponse, options.newResponse, this._headersToCheck)) {
if (process.env.NODE_ENV !== 'production') {
logger.log(`Newer response found (and cached) for:`, options.request.url);
}
const messageData = {
type: CACHE_UPDATED_MESSAGE_TYPE,
meta: CACHE_UPDATED_MESSAGE_META,
payload: this._generatePayload(options),
};
// For navigation requests, wait until the new window client exists
// before sending the message
if (options.request.mode === 'navigate') {
let resultingClientId;
if (options.event instanceof FetchEvent) {
resultingClientId = options.event.resultingClientId;
}
const resultingWin = await resultingClientExists(resultingClientId);
// Safari does not currently implement postMessage buffering and
// there's no good way to feature detect that, so to increase the
// chances of the message being delivered in Safari, we add a timeout.
// We also do this if `resultingClientExists()` didn't return a client,
// which means it timed out, so it's worth waiting a bit longer.
if (!resultingWin || isSafari) {
// 3500 is chosen because (according to CrUX data) 80% of mobile
// websites hit the DOMContentLoaded event in less than 3.5 seconds.
// And presumably sites implementing service worker are on the
// higher end of the performance spectrum.
await timeout(3500);
}
}
if (this._notifyAllClients) {
const windows = await self.clients.matchAll({ type: 'window' });
for (const win of windows) {
win.postMessage(messageData);
}
}
else {
// See https://github.com/GoogleChrome/workbox/issues/2895
if (options.event instanceof FetchEvent) {
const client = await self.clients.get(options.event.clientId);
client === null || client === void 0 ? void 0 : client.postMessage(messageData);
}
}
}
}
}
export { BroadcastCacheUpdate };