/* 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 { logger } from 'workbox-core/_private/logger.js'; import { WorkboxError } from 'workbox-core/_private/WorkboxError.js'; import { getFriendlyURL } from 'workbox-core/_private/getFriendlyURL.js'; import { normalizeHandler } from './utils/normalizeHandler.js'; import './_version.js'; /** * The Router can be used to process a FetchEvent through one or more * [Routes]{@link module:workbox-routing.Route} responding with a Request if * a matching route exists. * * If no route matches a given a request, the Router will use a "default" * handler if one is defined. * * Should the matching Route throw an error, the Router will use a "catch" * handler if one is defined to gracefully deal with issues and respond with a * Request. * * If a request matches multiple routes, the **earliest** registered route will * be used to respond to the request. * * @memberof module:workbox-routing */ class Router { /** * Initializes a new Router. */ constructor() { this._routes = new Map(); } /** * @return {Map>} routes A `Map` of HTTP * method name ('GET', etc.) to an array of all the corresponding `Route` * instances that are registered. */ get routes() { return this._routes; } /** * Adds a fetch event listener to respond to events when a route matches * the event's request. */ addFetchListener() { // See https://github.com/Microsoft/TypeScript/issues/28357#issuecomment-436484705 self.addEventListener('fetch', ((event) => { const { request } = event; const responsePromise = this.handleRequest({ request, event }); if (responsePromise) { event.respondWith(responsePromise); } })); } /** * Adds a message event listener for URLs to cache from the window. * This is useful to cache resources loaded on the page prior to when the * service worker started controlling it. * * The format of the message data sent from the window should be as follows. * Where the `urlsToCache` array may consist of URL strings or an array of * URL string + `requestInit` object (the same as you'd pass to `fetch()`). * * ``` * { * type: 'CACHE_URLS', * payload: { * urlsToCache: [ * './script1.js', * './script2.js', * ['./script3.js', {mode: 'no-cors'}], * ], * }, * } * ``` */ addCacheListener() { // See https://github.com/Microsoft/TypeScript/issues/28357#issuecomment-436484705 self.addEventListener('message', ((event) => { if (event.data && event.data.type === 'CACHE_URLS') { const { payload } = event.data; if (process.env.NODE_ENV !== 'production') { logger.debug(`Caching URLs from the window`, payload.urlsToCache); } const requestPromises = Promise.all(payload.urlsToCache.map((entry) => { if (typeof entry === 'string') { entry = [entry]; } const request = new Request(...entry); return this.handleRequest({ request }); // TODO(philipwalton): TypeScript errors without this typecast for // some reason (probably a bug). The real type here should work but // doesn't: `Array | undefined>`. })); // TypeScript event.waitUntil(requestPromises); // If a MessageChannel was used, reply to the message on success. if (event.ports && event.ports[0]) { requestPromises.then(() => event.ports[0].postMessage(true)); } } })); } /** * Apply the routing rules to a FetchEvent object to get a Response from an * appropriate Route's handler. * * @param {Object} options * @param {Request} options.request The request to handle (this is usually * from a fetch event, but it does not have to be). * @param {FetchEvent} [options.event] The event that triggered the request, * if applicable. * @return {Promise|undefined} A promise is returned if a * registered route can handle the request. If there is no matching * route and there's no `defaultHandler`, `undefined` is returned. */ handleRequest({ request, event }) { if (process.env.NODE_ENV !== 'production') { assert.isInstance(request, Request, { moduleName: 'workbox-routing', className: 'Router', funcName: 'handleRequest', paramName: 'options.request', }); } const url = new URL(request.url, location.href); if (!url.protocol.startsWith('http')) { if (process.env.NODE_ENV !== 'production') { logger.debug(`Workbox Router only supports URLs that start with 'http'.`); } return; } const { params, route } = this.findMatchingRoute({ url, request, event }); let handler = route && route.handler; const debugMessages = []; if (process.env.NODE_ENV !== 'production') { if (handler) { debugMessages.push([ `Found a route to handle this request:`, route, ]); if (params) { debugMessages.push([ `Passing the following params to the route's handler:`, params, ]); } } } // If we don't have a handler because there was no matching route, then // fall back to defaultHandler if that's defined. if (!handler && this._defaultHandler) { if (process.env.NODE_ENV !== 'production') { debugMessages.push(`Failed to find a matching route. Falling ` + `back to the default handler.`); } handler = this._defaultHandler; } if (!handler) { if (process.env.NODE_ENV !== 'production') { // No handler so Workbox will do nothing. If logs is set of debug // i.e. verbose, we should print out this information. logger.debug(`No route found for: ${getFriendlyURL(url)}`); } return; } if (process.env.NODE_ENV !== 'production') { // We have a handler, meaning Workbox is going to handle the route. // print the routing details to the console. logger.groupCollapsed(`Router is responding to: ${getFriendlyURL(url)}`); debugMessages.forEach((msg) => { if (Array.isArray(msg)) { logger.log(...msg); } else { logger.log(msg); } }); logger.groupEnd(); } // Wrap in try and catch in case the handle method throws a synchronous // error. It should still callback to the catch handler. let responsePromise; try { responsePromise = handler.handle({ url, request, event, params }); } catch (err) { responsePromise = Promise.reject(err); } if (responsePromise instanceof Promise && this._catchHandler) { responsePromise = responsePromise.catch((err) => { if (process.env.NODE_ENV !== 'production') { // Still include URL here as it will be async from the console group // and may not make sense without the URL logger.groupCollapsed(`Error thrown when responding to: ` + ` ${getFriendlyURL(url)}. Falling back to Catch Handler.`); logger.error(`Error thrown by:`, route); logger.error(err); logger.groupEnd(); } return this._catchHandler.handle({ url, request, event }); }); } return responsePromise; } /** * Checks a request and URL (and optionally an event) against the list of * registered routes, and if there's a match, returns the corresponding * route along with any params generated by the match. * * @param {Object} options * @param {URL} options.url * @param {Request} options.request The request to match. * @param {Event} [options.event] The corresponding event (unless N/A). * @return {Object} An object with `route` and `params` properties. * They are populated if a matching route was found or `undefined` * otherwise. */ findMatchingRoute({ url, request, event }) { if (process.env.NODE_ENV !== 'production') { assert.isInstance(url, URL, { moduleName: 'workbox-routing', className: 'Router', funcName: 'findMatchingRoute', paramName: 'options.url', }); assert.isInstance(request, Request, { moduleName: 'workbox-routing', className: 'Router', funcName: 'findMatchingRoute', paramName: 'options.request', }); } const routes = this._routes.get(request.method) || []; for (const route of routes) { let params; const matchResult = route.match({ url, request, event }); if (matchResult) { // See https://github.com/GoogleChrome/workbox/issues/2079 params = matchResult; if (Array.isArray(matchResult) && matchResult.length === 0) { // Instead of passing an empty array in as params, use undefined. params = undefined; } else if ((matchResult.constructor === Object && Object.keys(matchResult).length === 0)) { // Instead of passing an empty object in as params, use undefined. params = undefined; } else if (typeof matchResult === 'boolean') { // For the boolean value true (rather than just something truth-y), // don't set params. // See https://github.com/GoogleChrome/workbox/pull/2134#issuecomment-513924353 params = undefined; } // Return early if have a match. return { route, params }; } } // If no match was found above, return and empty object. return {}; } /** * Define a default `handler` that's called when no routes explicitly * match the incoming request. * * Without a default handler, unmatched requests will go against the * network as if there were no service worker present. * * @param {module:workbox-routing~handlerCallback} handler A callback * function that returns a Promise resulting in a Response. */ setDefaultHandler(handler) { this._defaultHandler = normalizeHandler(handler); } /** * If a Route throws an error while handling a request, this `handler` * will be called and given a chance to provide a response. * * @param {module:workbox-routing~handlerCallback} handler A callback * function that returns a Promise resulting in a Response. */ setCatchHandler(handler) { this._catchHandler = normalizeHandler(handler); } /** * Registers a route with the router. * * @param {module:workbox-routing.Route} route The route to register. */ registerRoute(route) { if (process.env.NODE_ENV !== 'production') { assert.isType(route, 'object', { moduleName: 'workbox-routing', className: 'Router', funcName: 'registerRoute', paramName: 'route', }); assert.hasMethod(route, 'match', { moduleName: 'workbox-routing', className: 'Router', funcName: 'registerRoute', paramName: 'route', }); assert.isType(route.handler, 'object', { moduleName: 'workbox-routing', className: 'Router', funcName: 'registerRoute', paramName: 'route', }); assert.hasMethod(route.handler, 'handle', { moduleName: 'workbox-routing', className: 'Router', funcName: 'registerRoute', paramName: 'route.handler', }); assert.isType(route.method, 'string', { moduleName: 'workbox-routing', className: 'Router', funcName: 'registerRoute', paramName: 'route.method', }); } if (!this._routes.has(route.method)) { this._routes.set(route.method, []); } // Give precedence to all of the earlier routes by adding this additional // route to the end of the array. this._routes.get(route.method).push(route); } /** * Unregisters a route with the router. * * @param {module:workbox-routing.Route} route The route to unregister. */ unregisterRoute(route) { if (!this._routes.has(route.method)) { throw new WorkboxError('unregister-route-but-not-found-with-method', { method: route.method, }); } const routeIndex = this._routes.get(route.method).indexOf(route); if (routeIndex > -1) { this._routes.get(route.method).splice(routeIndex, 1); } else { throw new WorkboxError('unregister-route-route-not-registered'); } } } export { Router };