Question

我有一个服务工作者的代码：

'use strict';

// Incrementing CACHE_VERSION will kick off the install event and force previously cached
// resources to be cached again.
const CACHE_VERSION = 1;
let CURRENT_CACHES = {
    offline: 'offline-v' + CACHE_VERSION
};
const OFFLINE_URL = 'offline.php';

function createCacheBustedRequest(url) {
    let request = new Request(url, {cache: 'reload'});
    // See https://fetch.spec.whatwg.org/#concept-request-mode
    // This is not yet supported in Chrome as of M48, so we need to explicitly check to see
    // if the cache: 'reload' option had any effect.
    if ('cache' in request) {
        return request;
    }

    // If {cache: 'reload'} didn't have any effect, append a cache-busting URL parameter instead.
    let bustedUrl = new URL(url, self.location.href);
    bustedUrl.search += (bustedUrl.search ? '&' : '') + 'cachebust=' + Date.now();
    return new Request(bustedUrl);
}

self.addEventListener('install', event => {
    event.waitUntil(
        // We can't use cache.add() here, since we want OFFLINE_URL to be the cache key, but
        // the actual URL we end up requesting might include a cache-busting parameter.
        fetch(createCacheBustedRequest(OFFLINE_URL)).then(function(response) {
            return caches.open(CURRENT_CACHES.offline).then(function(cache) {
                return cache.put(OFFLINE_URL, response);
            });
        })
    );
});

self.addEventListener('activate', event => {
    // Delete all caches that aren't named in CURRENT_CACHES.
    // While there is only one cache in this example, the same logic will handle the case where
    // there are multiple versioned caches.
    let expectedCacheNames = Object.keys(CURRENT_CACHES).map(function(key) {
        return CURRENT_CACHES[key];
    });

event.waitUntil(
    caches.keys().then(cacheNames => {
        return Promise.all(
            cacheNames.map(cacheName => {
                if (expectedCacheNames.indexOf(cacheName) === -1) {
    // If this cache name isn't present in the array of "expected" cache names,
    // then delete it.
    console.log('Deleting out of date cache:', cacheName);
    return caches.delete(cacheName);
}
})
);
})
);
});

self.addEventListener('fetch', event => {
    // We only want to call event.respondWith() if this is a navigation request
    // for an HTML page.
    // request.mode of 'navigate' is unfortunately not supported in Chrome
    // versions older than 49, so we need to include a less precise fallback,
    // which checks for a GET request with an Accept: text/html header.
    if (event.request.mode === 'navigate' ||
        (event.request.method === 'GET' &&
            event.request.headers.get('accept').includes('text/html'))) {
    console.log('Handling fetch event for', event.request.url);
    event.respondWith(
        fetch(createCacheBustedRequest(event.request.url)).catch(error => {
            // The catch is only triggered if fetch() throws an exception, which will most likely
            // happen due to the server being unreachable.
            // If fetch() returns a valid HTTP response with an response code in the 4xx or 5xx
            // range, the catch() will NOT be called. If you need custom handling for 4xx or 5xx
            // errors, see https://github.com/GoogleChrome/samples/tree/gh-pages/service-worker/fallback-response
            console.log('Fetch failed; returning offline page instead.', error);
    return caches.match(OFFLINE_URL);
})
);
}

// If our if() condition is false, then this fetch handler won't intercept the request.
// If there are any other fetch handlers registered, they will get a chance to call
// event.respondWith(). If no fetch handlers call event.respondWith(), the request will be
// handled by the browser as if there were no service worker involvement.
});

怎么可能以某种方式使它不必在缓存中保存任何东西？有问题的webapp始终需要连接。因此，此服务工作者的主要目的是有资格进行电话安装并具有稍后的推送通知功能。

Answer 1

经过一些在线研究，这是最好的解决方案：

sw_install.js

    console.log('Started', self);
self.addEventListener('install', function(event) {
    self.skipWaiting();
    console.log('Installed', event);
});
self.addEventListener('activate', function(event) {
    console.log('Activated', event);
});
self.addEventListener('push', function(event) {
    console.log('Push message received', event);
    // TODO
});

main.js

    if ('serviceWorker' in navigator) {
    console.log('Service Worker is supported');
    navigator.serviceWorker.register('sw_install.js').then(function(reg){
        console.log(':^)', reg);
        // TODO
    }).catch(function(err) {
        console.log(':^(', err);
    });
}

Answer 2

您可以使用npm sw-toolbox库（https://www.npmjs.com/package/sw-toolbox）。

<强> main.js

if (navigator.serviceWorker){
  navigator.serviceWorker.register('/service-worker.js', {scope: './'})
        .then(function (registration) {
            console.log("sw registered",registration);
        })
        .catch(function (e) {
            console.error("error",e);
        })
    } else {
        console.log('Service Worker is not supported in this browser.')
    }
}

<强>服务worker.js

(global => {
  'use strict';
  // Load the sw-tookbox library.
  importScripts('/js/sw-toolbox.js');

  var precache_urls = [
      '/index.html',
      '/img/logo.png',
      '/img/main.png'
  ];

  //for debugging only
  global.toolbox.options.debug = true;

  global.toolbox.router.get('/img/(.*)', self.toolbox.cacheFirst, {
  cache: {
    name: "Images",
    maxEntries: 10
    }
  });
  global.toolbox.router.default = global.toolbox.networkFirst;

  global.addEventListener('install', event => event.waitUntil(global.skipWaiting()));
  global.addEventListener('activate', event => event.waitUntil(global.clients.claim()));
  global.addEventListener('push', event => {
    var pushObj = event.data.json();
    var pushData = pushObj.data;

    // push payload if there, if not make an ajax get call to get it (can use fetch)
    var title = pushData && pushData.title;
    var body = pushData && pushData.body;
    var icon = '/img/logo.png';
                event.waitUntil(global.registration.showNotification(title, {
                body: body,
                icon: icon,
                badge: icon
                data:pushData
            }));

         });
  global.addEventListener('notificationclick', event => {
    event.notification.close();
    var url = event.notification.data.url|| '/';
    event.waitUntil(
      clients.matchAll({
        type: 'window'
      }).then(windowClients => {
        console.log('WindowClients', windowClients);
        for (var i = 0; i < windowClients.length; i++) {
          var client = windowClients[i];
          console.log('WindowClient', client);
          if (client.url === url && 'focus' in client) {
            return client.focus();
          }
       }
       if (clients.openWindow) {
         return clients.openWindow(url);
       }
    }));
  });
})(self);

服务人员基本设置

2 个答案: