PWA：渐进式网页应用、Service Worker 和清单的基础知识

if ('serviceWorker' in navigator) {
  navigator.serviceWorker.register('/sw.js')
    .then(registration => {
      console.log('SW 已注册：', registration.scope);
    })
    .catch(error => {
      console.log('SW 注册失败：', error);
    });
}

self.addEventListener('install', event => {
  event.waitUntil(
    caches.open('pwa-cache-v1').then(cache => {
      return cache.addAll([
        '/',
        '/index.html',
        '/styles/main.css',
        '/scripts/app.js',
        '/images/logo.png'
      ]);
    })
  );
});

self.addEventListener('activate', event => {
  const cacheWhitelist = ['pwa-cache-v2'];
  event.waitUntil(
    caches.keys().then(cacheNames => {
      return Promise.all(
        cacheNames.map(cacheName => {
          if (!cacheWhitelist.includes(cacheName)) {
            return caches.delete(cacheName);
          }
        })
      );
    })
  );
});

self.addEventListener('fetch', event => {
  event.respondWith(
    caches.match(event.request).then(response => {
      return response || fetch(event.request).then(fetchResponse => {
        return caches.open('pwa-cache-v1').then(cache => {
          cache.put(event.request, fetchResponse.clone());
          return fetchResponse;
        });
      });
    })
  );
});

self.addEventListener('fetch', event => {
  event.respondWith(
    fetch(event.request).then(response => {
      return caches.open('pwa-dynamic-v1').then(cache => {
        cache.put(event.request, response.clone());
        return response;
      });
    }).catch(() => {
      return caches.match(event.request);
    })
  );
});

self.addEventListener('fetch', event => {
  event.respondWith(
    caches.match(event.request).then(cached => {
      const fetchPromise = fetch(event.request).then(response => {
        return caches.open('pwa-dynamic-v1').then(cache => {
          cache.put(event.request, response.clone());
          return response;
        });
      });
      return cached || fetchPromise;
    })
  );
});

{
  "name": "PWA Demo App",
  "short_name": "PWA Demo",
  "description": "演示 PWA 应用程序",
  "start_url": "/",
  "display": "standalone",
  "background_color": "#ffffff",
  "theme_color": "#3f51b5",
  "orientation": "portrait",
  "icons": [
    {
      "src": "/icons/icon-192x192.png",
      "sizes": "192x192",
      "type": "image/png"
    },
    {
      "src": "/icons/icon-512x512.png",
      "sizes": "512x512",
      "type": "image/png",
      "purpose": "any maskable"
    }
  ]
}

Notification.requestPermission().then(permission => {
  if (permission === 'granted') {
    console.log('推送已允许');
  }
});

self.addEventListener('push', event => {
  const data = event.data.json();
  self.registration.showNotification(data.title, {
    body: data.body,
    icon: '/icons/icon-192x192.png',
    badge: '/icons/badge-72x72.png',
    actions: [
      { action: 'open', title: '打开' },
      { action: 'close', title: '关闭' }
    ]
  });
});

self.addEventListener('notificationclick', event => {
  event.notification.close();
  if (event.action === 'open') {
    clients.openWindow('/');
  }
});

self.addEventListener('fetch', event => {
  event.respondWith(
    caches.match(event.request).then(response => {
      return response || fetch(event.request);
    }).catch(() => {
      return caches.match('/offline.html');
    })
  );
});

self.addEventListener('sync', event => {
  if (event.tag === 'sync-messages') {
    event.waitUntil(sendMessages());
  }
});

function sendMessages() {
  return caches.open('pwa-pending-v1').then(cache => {
    return cache.keys().then(requests => {
      return Promise.all(requests.map(request => {
        return fetch(request).then(() => cache.delete(request));
      }));
    });
  });
}

import { precacheAndRoute } from 'workbox-precaching';
import { registerRoute } from 'workbox-routing';
import { StaleWhileRevalidate } from 'workbox-strategies';

precacheAndRoute(self.__WB_MANIFEST);

registerRoute(
  /\.(?:png|jpg|jpeg|svg|gif)$/,
  new StaleWhileRevalidate()
);