semaphore/src/service-worker.js

import {
  assets as __assets__,
  shell as __shell__,
  routes as __routes__
} from '../__sapper__/service-worker.js'
import { get, post } from './routes/_utils/ajax.js'
import { setWebShareData, closeKeyValIDBConnection } from './routes/_database/webShare.js'
import { getKnownInstances } from './routes/_database/knownInstances.js'
import { basename } from './routes/_api/utils.js'

const timestamp = process.env.SAPPER_TIMESTAMP
const ASSETS = `assets_${timestamp}`
const WEBPACK_ASSETS = `webpack_assets_${timestamp}`

const ON_DEMAND_CACHE = [
  {
    regex: /tesseract-core\.wasm/,
    cache: WEBPACK_ASSETS
  },
  {
    regex: /traineddata\.gz/,
    cache: ASSETS
  },
  {
    regex: /\$polyfill\$/,
    cache: WEBPACK_ASSETS
  },
  {
    regex: /TwemojiCountryFlags\.woff2/,
    cache: ASSETS
  },
  {
    regex: /_splash\.png$/,
    cache: ASSETS
  }
]

// `static` is an array of everything in the `static` directory
const assets = __assets__
  .map(file => file.startsWith('/') ? file : `/${file}`)
  .filter(filename => !filename.endsWith('.map'))
  .filter(filename => filename !== '/robots.txt')
  .filter(filename => !filename.includes('traineddata.gz')) // cache on-demand
  .filter(filename => !filename.endsWith('.webapp')) // KaiOS manifest
  .filter(filename => !/emoji-.*?\.json$/.test(filename)) // useless to cache; it already goes in IndexedDB
  .filter(filename => !/screenshot-.*?\.png/.test(filename)) // only used during PWA installation, don't bother caching
  .filter(filename => !/TwemojiCountryFlags\.woff2/.test(filename)) // cache on-demand
  .filter(filename => !/_splash\.png$/.test(filename)) // only used for iOS PWA splash screen, cache on-demand

// `shell` is an array of all the files generated by webpack
// also contains '/index.html' for some reason
const webpackAssets = __shell__
  .filter(filename => !filename.endsWith('.map')) // don't bother with sourcemaps
  .filter(filename => !filename.includes('tesseract-core.wasm')) // cache on-demand
  .filter(filename => !filename.includes('LICENSE')) // don't bother with license files
  .filter(filename => !filename.includes('$polyfill$')) // polyfills are cached dynamically

// `routes` is an array of `{ pattern: RegExp }` objects that
// match the pages in your src
const routes = __routes__

self.addEventListener('install', event => {
  event.waitUntil((async () => {
    await Promise.all([
      caches.open(WEBPACK_ASSETS).then(cache => cache.addAll(webpackAssets)),
      caches.open(ASSETS).then(cache => cache.addAll(assets))
    ])
    // We shouldn't have to do this, but the previous page could be an old one,
    // which would not send us a postMessage to skipWaiting().
    // See https://github.com/nolanlawson/pinafore/issues/1243
    self.skipWaiting()
  })())
})

self.addEventListener('activate', event => {
  event.waitUntil((async () => {
    const keys = await caches.keys()

    // delete old asset/ondemand caches
    for (const key of keys) {
      if (key !== ASSETS &&
        !key.startsWith('webpack_assets_')) {
        await caches.delete(key)
      }
    }

    // for webpack static, keep the two latest builds because we may need
    // them when the service worker has installed but the page has not
    // yet reloaded (e.g. when it gives the toast saying "please reload"
    // but then you don't refresh and instead load an async chunk)
    const webpackKeysToDelete = keys
      .filter(key => key.startsWith('webpack_assets_'))
      .sort((a, b) => {
        const aTimestamp = parseInt(a.substring(15), 10)
        const bTimestamp = parseInt(b.substring(15), 10)
        return bTimestamp < aTimestamp ? -1 : 1
      })
      .slice(2)

    for (const key of webpackKeysToDelete) {
      await caches.delete(key)
    }

    await self.clients.claim()
  })())
})

self.addEventListener('fetch', event => {
  const req = event.request
  const url = new URL(req.url)

  // don't try to handle e.g. data: URIs
  if (!url.protocol.startsWith('http')) {
    return
  }

  event.respondWith((async () => {
    const sameOrigin = url.origin === self.origin

    if (sameOrigin) {
      if (req.method === 'POST' && url.pathname === '/share') {
        // handle Web Share Target requests (see manifest.json)
        const formData = await req.formData()
        const title = formData.get('title')
        const text = formData.get('text')
        const url = formData.get('url')
        const file = formData.get('file')
        await setWebShareData({ title, text, url, file })
        await closeKeyValIDBConnection() // don't need to keep the IDB connection open
        return Response.redirect(
          '/?pwa=true&compose=true', // pwa=true because this can only be invoked from a PWA
          303 // 303 recommended by https://web.dev/web-share-target/
        )
      }

      // always serve webpack-generated resources and
      // static from the cache if possible
      const response = await caches.match(req)
      if (response) {
        return response
      }

      for (const { regex, cache } of ON_DEMAND_CACHE) {
        if (regex.test(url.pathname)) {
          // cache this on-demand
          const response = await fetch(req)
          if (response && response.status >= 200 && response.status < 300) {
            const clonedResponse = response.clone()
            /* no await */
            caches.open(cache).then(cache => cache.put(req, clonedResponse))
          }
          return response
        }
      }

      // for routes, serve the /service-worker-index.html file from the most recent
      // static cache
      if (routes.find(route => route.pattern.test(url.pathname))) {
        const response = await caches.match('/service-worker-index.html')
        if (response) {
          return response
        }
      }
    }

    // for everything else, go network-only
    return fetch(req)
  })())
})

self.addEventListener('push', event => {
  event.waitUntil((async () => {
    const data = event.data.json()
    // If there is only once instance, then we know for sure that the push notification came from it
    const knownInstances = await getKnownInstances()
    if (knownInstances.length !== 1) {
      // TODO: Mastodon currently does not tell us which instance the push notification came from.
      // So we have to guess and currently just choose the first one. We _could_ locally store the instance that
      // currently has push notifications enabled, but this would only work for one instance at a time.
      // See: https://github.com/mastodon/mastodon/issues/22183
      await showSimpleNotification(data)
      return
    }

    const origin = basename(knownInstances[0])
    try {
      const notification = await get(`${origin}/api/v1/notifications/${data.notification_id}`, {
        Authorization: `Bearer ${data.access_token}`
      }, { timeout: 2000 })

      await showRichNotification(data, notification)
    } catch (e) {
      await showSimpleNotification(data)
    }
  })())
})

async function showSimpleNotification (data) {
  await self.registration.showNotification(data.title, {
    badge: '/icon-push-badge.png',
    icon: data.icon,
    body: data.body,
    tag: data.notification_id,
    data: {
      url: `${self.origin}/notifications`
    }
  })
}

async function showRichNotification (data, notification) {
  const { icon, body } = data
  const tag = notification.id
  const { origin } = self.location
  const badge = '/icon-push-badge.png'

  switch (notification.type) {
    case 'follow':
    case 'follow_request':
    case 'admin.report':
    case 'admin.sign_up': {
      await self.registration.showNotification(data.title, {
        badge,
        icon,
        body,
        tag,
        data: {
          url: `${origin}/accounts/${notification.account.id}`
        }
      })
      break
    }
    case 'reblog':
    case 'favourite':
    case 'status':
    case 'poll': {
      await self.registration.showNotification(data.title, {
        badge,
        icon,
        body,
        tag,
        data: {
          url: `${origin}/statuses/${notification.status.id}`
        }
      })
      break
    }
    case 'mention': {
      const isPublic = ['public', 'unlisted'].includes(notification.status.visibility)
      const actions = [
        isPublic && {
          action: 'reblog',
          icon: '/icon-push-fa-retweet.png', // generated manually from font-awesome-svg
          title: 'intl.reblog'
        },
        {
          action: 'favourite',
          icon: '/icon-push-fa-star.png', // generated manually from font-awesome-svg
          title: 'intl.favorite'
        }
      ].filter(Boolean)

      await self.registration.showNotification(data.title, {
        badge,
        icon,
        body,
        tag,
        data: {
          instance: new URL(data.icon).origin,
          status_id: notification.status.id,
          access_token: data.access_token,
          url: `${origin}/statuses/${notification.status.id}`
        },
        actions
      })
      break
    }
  }
}

const cloneNotification = notification => {
  const clone = {}

  for (const k in notification) {
    // deliberately not doing a hasOwnProperty check, but skipping
    // functions and null props like onclick and onshow and showTrigger
    if (typeof notification[k] !== 'function' && notification[k] !== null) {
      clone[k] = notification[k]
    }
  }

  return clone
}

const updateNotificationWithoutAction = (notification, action) => {
  const newNotification = cloneNotification(notification)

  newNotification.actions = newNotification.actions.filter(item => item.action !== action)

  return self.registration.showNotification(newNotification.title, newNotification)
}

self.addEventListener('notificationclick', event => {
  event.waitUntil((async () => {
    switch (event.action) {
      case 'reblog': {
        const url = `${event.notification.data.instance}/api/v1/statuses/${event.notification.data.status_id}/reblog`
        await post(url, null, {
          Authorization: `Bearer ${event.notification.data.access_token}`
        })
        await updateNotificationWithoutAction(event.notification, 'reblog')
        break
      }
      case 'favourite': {
        const url = `${event.notification.data.instance}/api/v1/statuses/${event.notification.data.status_id}/favourite`
        await post(url, null, {
          Authorization: `Bearer ${event.notification.data.access_token}`
        })
        await updateNotificationWithoutAction(event.notification, 'favourite')
        break
      }
      default: {
        await self.clients.openWindow(event.notification.data.url)
        await event.notification.close()
        break
      }
    }
  })())
})

self.addEventListener('message', (event) => {
  switch (event.data) {
    case 'skip-waiting':
      self.skipWaiting()
      break
  }
})