GoScrobble/web/node_modules/workbox-strategies/NetworkFirst.js

/*
  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 { cacheNames } from 'workbox-core/_private/cacheNames.js';
import { cacheWrapper } from 'workbox-core/_private/cacheWrapper.js';
import { fetchWrapper } from 'workbox-core/_private/fetchWrapper.js';
import { getFriendlyURL } from 'workbox-core/_private/getFriendlyURL.js';
import { logger } from 'workbox-core/_private/logger.js';
import { WorkboxError } from 'workbox-core/_private/WorkboxError.js';
import { messages } from './utils/messages.js';
import { cacheOkAndOpaquePlugin } from './plugins/cacheOkAndOpaquePlugin.js';
import './_version.js';
/**
 * An implementation of a
 * [network first]{@link https://developers.google.com/web/fundamentals/instant-and-offline/offline-cookbook/#network-falling-back-to-cache}
 * request strategy.
 *
 * By default, this strategy will cache responses with a 200 status code as
 * well as [opaque responses]{@link https://developers.google.com/web/tools/workbox/guides/handle-third-party-requests}.
 * Opaque responses are are cross-origin requests where the response doesn't
 * support [CORS]{@link https://enable-cors.org/}.
 *
 * If the network request fails, and there is no cache match, this will throw
 * a `WorkboxError` exception.
 *
 * @memberof module:workbox-strategies
 */
class NetworkFirst {
    /**
     * @param {Object} options
     * @param {string} options.cacheName Cache name to store and retrieve
     * requests. Defaults to cache names provided by
     * [workbox-core]{@link module:workbox-core.cacheNames}.
     * @param {Array<Object>} options.plugins [Plugins]{@link https://developers.google.com/web/tools/workbox/guides/using-plugins}
     * to use in conjunction with this caching strategy.
     * @param {Object} options.fetchOptions Values passed along to the
     * [`init`](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/fetch#Parameters)
     * of all fetch() requests made by this strategy.
     * @param {Object} options.matchOptions [`CacheQueryOptions`](https://w3c.github.io/ServiceWorker/#dictdef-cachequeryoptions)
     * @param {number} options.networkTimeoutSeconds If set, any network requests
     * that fail to respond within the timeout will fallback to the cache.
     *
     * This option can be used to combat
     * "[lie-fi]{@link https://developers.google.com/web/fundamentals/performance/poor-connectivity/#lie-fi}"
     * scenarios.
     */
    constructor(options = {}) {
        this._cacheName = cacheNames.getRuntimeName(options.cacheName);
        if (options.plugins) {
            const isUsingCacheWillUpdate = options.plugins.some((plugin) => !!plugin.cacheWillUpdate);
            this._plugins = isUsingCacheWillUpdate ?
                options.plugins : [cacheOkAndOpaquePlugin, ...options.plugins];
        }
        else {
            // No plugins passed in, use the default plugin.
            this._plugins = [cacheOkAndOpaquePlugin];
        }
        this._networkTimeoutSeconds = options.networkTimeoutSeconds || 0;
        if (process.env.NODE_ENV !== 'production') {
            if (this._networkTimeoutSeconds) {
                assert.isType(this._networkTimeoutSeconds, 'number', {
                    moduleName: 'workbox-strategies',
                    className: 'NetworkFirst',
                    funcName: 'constructor',
                    paramName: 'networkTimeoutSeconds',
                });
            }
        }
        this._fetchOptions = options.fetchOptions;
        this._matchOptions = options.matchOptions;
    }
    /**
     * This method will perform a request strategy and follows an API that
     * will work with the
     * [Workbox Router]{@link module:workbox-routing.Router}.
     *
     * @param {Object} options
     * @param {Request|string} options.request A request to run this strategy for.
     * @param {Event} [options.event] The event that triggered the request.
     * @return {Promise<Response>}
     */
    async handle({ event, request }) {
        const logs = [];
        if (typeof request === 'string') {
            request = new Request(request);
        }
        if (process.env.NODE_ENV !== 'production') {
            assert.isInstance(request, Request, {
                moduleName: 'workbox-strategies',
                className: 'NetworkFirst',
                funcName: 'handle',
                paramName: 'makeRequest',
            });
        }
        const promises = [];
        let timeoutId;
        if (this._networkTimeoutSeconds) {
            const { id, promise } = this._getTimeoutPromise({ request, event, logs });
            timeoutId = id;
            promises.push(promise);
        }
        const networkPromise = this._getNetworkPromise({ timeoutId, request, event, logs });
        promises.push(networkPromise);
        // Promise.race() will resolve as soon as the first promise resolves.
        let response = await Promise.race(promises);
        // If Promise.race() resolved with null, it might be due to a network
        // timeout + a cache miss. If that were to happen, we'd rather wait until
        // the networkPromise resolves instead of returning null.
        // Note that it's fine to await an already-resolved promise, so we don't
        // have to check to see if it's still "in flight".
        if (!response) {
            response = await networkPromise;
        }
        if (process.env.NODE_ENV !== 'production') {
            logger.groupCollapsed(messages.strategyStart('NetworkFirst', request));
            for (const log of logs) {
                logger.log(log);
            }
            messages.printFinalResponse(response);
            logger.groupEnd();
        }
        if (!response) {
            throw new WorkboxError('no-response', { url: request.url });
        }
        return response;
    }
    /**
     * @param {Object} options
     * @param {Request} options.request
     * @param {Array} options.logs A reference to the logs array
     * @param {Event} [options.event]
     * @return {Promise<Response>}
     *
     * @private
     */
    _getTimeoutPromise({ request, logs, event }) {
        let timeoutId;
        const timeoutPromise = new Promise((resolve) => {
            const onNetworkTimeout = async () => {
                if (process.env.NODE_ENV !== 'production') {
                    logs.push(`Timing out the network response at ` +
                        `${this._networkTimeoutSeconds} seconds.`);
                }
                resolve(await this._respondFromCache({ request, event }));
            };
            timeoutId = setTimeout(onNetworkTimeout, this._networkTimeoutSeconds * 1000);
        });
        return {
            promise: timeoutPromise,
            id: timeoutId,
        };
    }
    /**
     * @param {Object} options
     * @param {number|undefined} options.timeoutId
     * @param {Request} options.request
     * @param {Array} options.logs A reference to the logs Array.
     * @param {Event} [options.event]
     * @return {Promise<Response>}
     *
     * @private
     */
    async _getNetworkPromise({ timeoutId, request, logs, event }) {
        let error;
        let response;
        try {
            response = await fetchWrapper.fetch({
                request,
                event,
                fetchOptions: this._fetchOptions,
                plugins: this._plugins,
            });
        }
        catch (err) {
            error = err;
        }
        if (timeoutId) {
            clearTimeout(timeoutId);
        }
        if (process.env.NODE_ENV !== 'production') {
            if (response) {
                logs.push(`Got response from network.`);
            }
            else {
                logs.push(`Unable to get a response from the network. Will respond ` +
                    `with a cached response.`);
            }
        }
        if (error || !response) {
            response = await this._respondFromCache({ request, event });
            if (process.env.NODE_ENV !== 'production') {
                if (response) {
                    logs.push(`Found a cached response in the '${this._cacheName}'` +
                        ` cache.`);
                }
                else {
                    logs.push(`No response found in the '${this._cacheName}' cache.`);
                }
            }
        }
        else {
            // Keep the service worker alive while we put the request in the cache
            const responseClone = response.clone();
            const cachePut = cacheWrapper.put({
                cacheName: this._cacheName,
                request,
                response: responseClone,
                event,
                plugins: this._plugins,
            });
            if (event) {
                try {
                    // The event has been responded to so we can keep the SW alive to
                    // respond to the request
                    event.waitUntil(cachePut);
                }
                catch (err) {
                    if (process.env.NODE_ENV !== 'production') {
                        logger.warn(`Unable to ensure service worker stays alive when ` +
                            `updating cache for '${getFriendlyURL(request.url)}'.`);
                    }
                }
            }
        }
        return response;
    }
    /**
     * Used if the network timeouts or fails to make the request.
     *
     * @param {Object} options
     * @param {Request} request The request to match in the cache
     * @param {Event} [options.event]
     * @return {Promise<Object>}
     *
     * @private
     */
    _respondFromCache({ event, request }) {
        return cacheWrapper.match({
            cacheName: this._cacheName,
            request,
            event,
            matchOptions: this._matchOptions,
            plugins: this._plugins,
        });
    }
}
export { NetworkFirst };