RuoYi-Vue/browser-extension/multi-platform-publisher-1.1.17/background/service-worker.js

const VERSION = chrome.runtime.getManifest().version

const PLATFORM_URLS = Object.freeze({
  xiaohongshu: 'https://creator.xiaohongshu.com/publish/publish?source=official',
  douyin: 'https://creator.douyin.com/creator-micro/content/upload',
  wechat_channels: 'https://channels.weixin.qq.com/platform/post/create',
  bilibili: 'https://member.bilibili.com/platform/upload/video/frame',
  xianyu: 'https://www.goofish.pro/sale/product/add?from=%2Fon-sale'
})

const PLATFORM_HOSTS = Object.freeze({
  xiaohongshu: 'creator.xiaohongshu.com',
  douyin: 'creator.douyin.com',
  wechat_channels: 'channels.weixin.qq.com',
  bilibili: 'member.bilibili.com',
  xianyu: 'goofish.pro'
})

const TERMINAL_STATUSES = new Set(['READY_TO_PUBLISH', 'SUCCEEDED', 'FAILED', 'CANCELLED'])
const BATCH_ADVANCE_STATUSES = new Set(['READY_TO_PUBLISH', 'FAILED', 'LOGIN_REQUIRED', 'CANCELLED'])
const BATCH_WATCHDOG_PREFIX = 'publisher_batch_watchdog:'
const advancingBatches = new Set()

chrome.runtime.onInstalled.addListener(() => {
  chrome.storage.local.set({ publisherExtensionVersion: VERSION })
  configureSidePanel().catch(() => {})
  recoverStoredBatches().catch(() => {})
})

chrome.runtime.onStartup.addListener(() => {
  configureSidePanel().catch(() => {})
  recoverStoredBatches().catch(() => {})
})

configureSidePanel().catch(() => {})

chrome.alarms.onAlarm.addListener(alarm => {
  if (!alarm || !alarm.name.startsWith(BATCH_WATCHDOG_PREFIX)) return
  const batchId = alarm.name.slice(BATCH_WATCHDOG_PREFIX.length)
  continueTimedOutBatch(batchId).catch(() => {})
})

chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
  if (!message || typeof message.type !== 'string') return false

  if (message.type === 'ADMIN_PING') {
    sendResponse({ ok: isAllowedAdmin(sender.url), version: VERSION })
    return false
  }

  if (message.type === 'ADMIN_START_PUBLISH') {
    startPublish(message.payload, sender)
      .then(result => sendResponse({ ok: true, ...result }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'ADMIN_START_PUBLISH_BATCH') {
    startPublishBatch(message.payload, sender)
      .then(result => sendResponse({ ok: true, ...result }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'PLATFORM_READY') {
    resumeTaskForTab(sender.tab, message.platform)
      .then(result => sendResponse(result))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'PLATFORM_FILL_CONTENT') {
    fillPlatformContent(message.payload, sender)
      .then(result => sendResponse({ ok: true, ...result }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'PUBLISH_STATUS') {
    receivePlatformStatus(message.payload, sender)
      .then(() => sendResponse({ ok: true }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'SIDEPANEL_GET_TASKS') {
    listSidePanelTasks()
      .then(tasks => sendResponse({ ok: true, tasks }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'SIDEPANEL_RETRY_TASK') {
    retryTask(message.taskId)
      .then(result => sendResponse({ ok: true, ...result }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  if (message.type === 'SIDEPANEL_ACTIVATE_TASK') {
    activateTaskTab(message.taskId)
      .then(result => sendResponse({ ok: true, ...result }))
      .catch(error => sendResponse({ ok: false, message: readableError(error) }))
    return true
  }

  return false
})

chrome.tabs.onUpdated.addListener((tabId, changeInfo, tab) => {
  if (changeInfo.status !== 'complete') return
  getContextForTab(tabId).then(context => {
    if (!context || !isExpectedPlatformUrl(tab.url, context.platform)) return
    sendTaskMessage(tabId, context)
  }).catch(() => {})
})

chrome.tabs.onRemoved.addListener(tabId => {
  getContextForTab(tabId).then(async context => {
    if (!context) return
    if (!TERMINAL_STATUSES.has(context.status)) {
      await updateStatus(context, 'CANCELLED', '平台页面已关闭', '')
      await advanceBatch(context)
    }
    context.platformTabId = null
    context.closedAt = Date.now()
    await chrome.storage.local.set({ [taskKey(context.taskId)]: context })
    await chrome.storage.local.remove(tabKey(tabId))
  }).catch(() => {})
})

async function configureSidePanel() {
  if (!chrome.sidePanel || !chrome.sidePanel.setPanelBehavior) return
  await chrome.sidePanel.setPanelBehavior({ openPanelOnActionClick: true })
}

async function listSidePanelTasks() {
  const stored = await chrome.storage.local.get(null)
  const expiry = Date.now() - 4 * 60 * 60 * 1000
  const contexts = Object.keys(stored)
    .filter(key => key.startsWith('publisher_task_'))
    .map(key => stored[key])
    .filter(context => context && context.taskId && context.platform && context.createdAt >= expiry)
    .sort((left, right) => (right.createdAt || 0) - (left.createdAt || 0))
  const latestByPlatform = new Map()
  for (const context of contexts) {
    if (!latestByPlatform.has(context.platform)) latestByPlatform.set(context.platform, context)
  }
  return Array.from(latestByPlatform.values()).map(context => ({
    taskId: context.taskId,
    platform: context.platform,
    platformName: platformName(context.platform),
    title: context.task && context.task.title || '',
    status: context.status || 'PENDING',
    statusMessage: context.statusMessage || '',
    platformTabId: context.platformTabId || null,
    createdAt: context.createdAt || 0,
    canRetry: context.status !== 'SUCCEEDED'
  }))
}

async function activateTaskTab(taskId) {
  const context = await requireStoredTask(taskId)
  if (!context.platformTabId) throw new Error('平台页面已关闭，可点击刷新按钮重新打开')
  const tab = await chrome.tabs.get(context.platformTabId).catch(() => null)
  if (!tab) throw new Error('平台页面已关闭，可点击刷新按钮重新打开')
  await focusTab(tab)
  return { taskId: context.taskId, tabId: tab.id }
}

async function retryTask(taskId) {
  const context = await requireStoredTask(taskId)
  if (context.status === 'SUCCEEDED') throw new Error('已发布成功的任务不能重试，以免重复发布')
  context.status = 'OPENING'
  context.statusMessage = '正在从侧边栏重试'
  context.closedAt = null
  await updateStatus(context, 'OPENING', '正在重试' + platformName(context.platform) + '发布任务', '')

  let tab = context.platformTabId
    ? await chrome.tabs.get(context.platformTabId).catch(() => null)
    : null
  if (tab) {
    await chrome.storage.local.set({ [tabKey(tab.id)]: context.taskId })
    tab = await chrome.tabs.update(tab.id, { url: PLATFORM_URLS[context.platform], active: true })
  } else {
    tab = await chrome.tabs.create({ url: PLATFORM_URLS[context.platform], active: true })
  }
  context.platformTabId = tab.id
  await chrome.storage.local.set({
    [taskKey(context.taskId)]: context,
    [tabKey(tab.id)]: context.taskId
  })
  await focusTab(tab)
  return { taskId: context.taskId, tabId: tab.id }
}

async function requireStoredTask(taskId) {
  if (typeof taskId !== 'string' || !/^publish_[a-f0-9]{32}$/.test(taskId)) {
    throw new Error('发布任务编号无效')
  }
  const stored = await chrome.storage.local.get(taskKey(taskId))
  const context = stored[taskKey(taskId)]
  if (!context) throw new Error('发布任务已过期，请从后台重新创建')
  return context
}

async function focusTab(tab) {
  if (tab.windowId) await chrome.windows.update(tab.windowId, { focused: true }).catch(() => {})
  await chrome.tabs.update(tab.id, { active: true })
}

async function startPublish(payload, sender) {
  if (!isAllowedAdmin(sender.url) || !sender.tab) {
    throw new Error('发布请求不是来自允许的后台页面')
  }
  validatePayload(payload)
  const apiBaseUrl = normalizeApiBase(payload.apiBaseUrl, sender.url)
  const task = await fetchBridgeTask(apiBaseUrl, payload.taskId, payload.token)
  if (task.platform !== payload.platform || !PLATFORM_URLS[task.platform]) {
    throw new Error('任务平台与页面请求不一致')
  }

  const context = {
    taskId: payload.taskId,
    token: payload.token,
    apiBaseUrl,
    platform: task.platform,
    task,
    adminTabId: sender.tab.id,
    batchId: payload.batchId || '',
    status: 'OPENING',
    createdAt: Date.now()
  }

  await updateStatus(context, 'OPENING', '正在打开' + platformName(task.platform) + '创作者中心', '')
  const tab = await chrome.tabs.create({ url: PLATFORM_URLS[task.platform], active: true })
  context.platformTabId = tab.id
  await chrome.storage.local.set({
    [taskKey(context.taskId)]: context,
    [tabKey(tab.id)]: context.taskId
  })
  await sendTaskMessageWithRetry(tab.id, context, 15000)
  return { taskId: context.taskId, tabId: tab.id }
}

async function startPublishBatch(payload, sender) {
  if (!isAllowedAdmin(sender.url) || !sender.tab) {
    throw new Error('批量发布请求不是来自允许的后台页面')
  }
  if (!payload || typeof payload.batchId !== 'string'
      || !/^publish_batch_[a-zA-Z0-9_]+$/.test(payload.batchId)
      || !Array.isArray(payload.tasks) || !payload.tasks.length || payload.tasks.length > 5) {
    throw new Error('多平台发布批次参数不正确')
  }
  const platforms = new Set()
  const tasks = payload.tasks.map(item => {
    const task = {
      taskId: item.taskId,
      token: item.token,
      platform: item.platform,
      apiBaseUrl: payload.apiBaseUrl
    }
    validatePayload(task)
    if (platforms.has(task.platform)) throw new Error('多平台发布中存在重复平台')
    platforms.add(task.platform)
    return task
  })
  const batch = {
    batchId: payload.batchId,
    tasks,
    nextIndex: 0,
    currentTaskId: '',
    adminTabId: sender.tab.id,
    adminUrl: sender.url,
    createdAt: Date.now()
  }
  await chrome.storage.local.set({ [batchKey(batch.batchId)]: batch })
  await processNextBatchTask(batch.batchId)
  return { batchId: batch.batchId, taskCount: tasks.length }
}

async function processNextBatchTask(batchId) {
  const stored = await chrome.storage.local.get(batchKey(batchId))
  const batch = stored[batchKey(batchId)]
  if (!batch || batch.currentTaskId) return
  if (batch.nextIndex >= batch.tasks.length) {
    await chrome.storage.local.remove(batchKey(batchId))
    return
  }

  const task = batch.tasks[batch.nextIndex]
  batch.nextIndex += 1
  batch.currentTaskId = task.taskId
  await chrome.storage.local.set({ [batchKey(batchId)]: batch })
  await scheduleBatchWatchdog(batchId)
  try {
    await startPublish(
      { ...task, batchId },
      { url: batch.adminUrl, tab: { id: batch.adminTabId } }
    )
  } catch (error) {
    const context = {
      taskId: task.taskId,
      token: task.token,
      apiBaseUrl: task.apiBaseUrl,
      platform: task.platform,
      adminTabId: batch.adminTabId,
      batchId
    }
    try {
      await updateStatus(context, 'FAILED', '平台任务启动失败', readableError(error))
    } catch (ignored) {}
    await advanceBatch(context)
  }
}

async function advanceBatch(context) {
  if (!context || !context.batchId) return
  if (advancingBatches.has(context.batchId)) return
  advancingBatches.add(context.batchId)
  let shouldProcessNext = false
  try {
    const key = batchKey(context.batchId)
    const stored = await chrome.storage.local.get(key)
    const batch = stored[key]
    if (!batch || batch.currentTaskId !== context.taskId) return
    await chrome.alarms.clear(batchWatchdogName(context.batchId))
    batch.currentTaskId = ''
    await chrome.storage.local.set({ [key]: batch })
    shouldProcessNext = true
  } finally {
    advancingBatches.delete(context.batchId)
  }
  // 启动下一项前必须先释放批次锁。否则下一项在启动阶段失败时，
  // 它的补偿推进会因同一把锁仍被占用而直接返回，整个批次就会停住。
  if (shouldProcessNext) await processNextBatchTask(context.batchId)
}

async function scheduleBatchWatchdog(batchId) {
  await chrome.alarms.create(batchWatchdogName(batchId), { delayInMinutes: 4 })
}

async function continueTimedOutBatch(batchId) {
  const stored = await chrome.storage.local.get(batchKey(batchId))
  const batch = stored[batchKey(batchId)]
  if (!batch || !batch.currentTaskId) return
  const taskId = batch.currentTaskId
  const taskStored = await chrome.storage.local.get(taskKey(taskId))
  const context = taskStored[taskKey(taskId)] || {
    taskId,
    batchId,
    token: '',
    apiBaseUrl: '',
    platform: ''
  }
  context.batchId = batchId
  if (context.token && context.apiBaseUrl && !TERMINAL_STATUSES.has(context.status)) {
    try {
      await updateStatus(
        context,
        'FAILED',
        '当前平台处理超时，批次已自动继续',
        '扩展超过4分钟未收到完成信号，请检查该平台页面'
      )
    } catch (ignored) {}
  }
  await advanceBatch({ batchId, taskId })
}

async function recoverStoredBatches() {
  const stored = await chrome.storage.local.get(null)
  const batches = Object.keys(stored)
    .filter(key => key.startsWith('publisher_batch_'))
    .map(key => stored[key])
    .filter(Boolean)
  for (const batch of batches) {
    if (!batch.currentTaskId) {
      await processNextBatchTask(batch.batchId)
      continue
    }
    const context = stored[taskKey(batch.currentTaskId)]
    if (context && BATCH_ADVANCE_STATUSES.has(context.status)) {
      await advanceBatch(context)
    } else {
      await scheduleBatchWatchdog(batch.batchId)
    }
  }
}

async function resumeTaskForTab(tab, platform) {
  if (!tab || !tab.id) return { ok: false, message: '无法识别平台标签页' }
  const context = await getContextForTab(tab.id)
  if (!context) return { ok: false, message: '当前标签页没有待执行任务' }
  if (context.platform !== platform || !isExpectedPlatformUrl(tab.url, platform)) {
    return { ok: false, message: '平台标签页与发布任务不匹配' }
  }
  if (['SUCCEEDED', 'FAILED', 'CANCELLED'].includes(context.status)) {
    return { ok: false, message: '发布任务已经结束' }
  }
  await sendTaskMessage(tab.id, context)
  return { ok: true, taskId: context.taskId }
}

async function sendTaskMessage(tabId, context) {
  try {
    await chrome.tabs.sendMessage(tabId, {
      type: context.status === 'READY_TO_PUBLISH' ? 'WATCH_PUBLISH_OUTCOME' : 'RUN_PUBLISH',
      payload: {
        task: context.task,
        taskId: context.taskId,
        token: context.token,
        apiBaseUrl: context.apiBaseUrl,
        batchId: context.batchId || ''
      }
    })
    return true
  } catch (error) {
    // 页面脚本可能仍在加载，PLATFORM_READY 会再次触发发送。
    return false
  }
}

async function sendTaskMessageWithRetry(tabId, context, timeout) {
  const started = Date.now()
  while (Date.now() - started < timeout) {
    if (await sendTaskMessage(tabId, context)) return true
    await sleep(500)
  }
  // 登录页或较慢的页面仍可在加载完成后通过 PLATFORM_READY 恢复任务。
  return false
}

async function receivePlatformStatus(payload, sender) {
  if (!payload || !payload.taskId || !payload.status || !sender.tab) {
    throw new Error('平台状态参数不完整')
  }
  const context = await getContextForTab(sender.tab.id)
  if (!context || context.taskId !== payload.taskId) {
    throw new Error('未找到当前平台标签页对应的发布任务')
  }
  if (!isExpectedPlatformUrl(sender.url, context.platform)) {
    throw new Error('平台状态来源不可信')
  }
  let statusError = null
  try {
    await updateStatus(context, payload.status, payload.message || '', payload.error || '')
  } catch (error) {
    statusError = error
  }
  // 批次推进以平台页面的完成信号为准。后台状态接口偶发失败时，
  // 仍继续打开下一平台，避免一个回写请求把整个多平台批次卡住。
  if (BATCH_ADVANCE_STATUSES.has(payload.status)) {
    await advanceBatch(context)
  }
  if (statusError) throw statusError
}

async function fillPlatformContent(payload, sender) {
  if (!sender.tab || !sender.tab.id || !payload || payload.platform !== 'wechat_channels'
      || !isExpectedPlatformUrl(sender.url, payload.platform)) {
    throw new Error('文案填写请求来源不可信')
  }
  const value = String(payload.value || '')
  if (!value || value.length > 10000) throw new Error('视频号发布文案为空或过长')
  const results = await chrome.scripting.executeScript({
    target: { tabId: sender.tab.id, allFrames: true },
    world: 'MAIN',
    func: fillWechatChannelsContent,
    args: [value]
  })
  const frameResults = results.map(item => item.result).filter(Boolean)
  const hit = frameResults.find(item => item.ok)
  if (!hit) {
    const details = frameResults.map(item => (item.url || 'unknown') + ': ' + (item.error || '未找到编辑器'))
    throw new Error('视频号文案写入失败；' + details.join(' | ').slice(0, 800))
  }
  return { frameUrl: hit.url }
}

function fillWechatChannelsContent(value) {
  const normalize = text => String(text || '').replace(/\s+/g, ' ').trim()
  const isVisible = element => {
    if (!element || !element.isConnected) return false
    const rect = element.getBoundingClientRect()
    const style = getComputedStyle(element)
    return rect.width > 0 && rect.height > 0
      && style.display !== 'none' && style.visibility !== 'hidden'
  }
  const queryAllDeep = (root, selector) => {
    const matches = Array.from(root.querySelectorAll(selector))
    for (const element of root.querySelectorAll('*')) {
      if (element.shadowRoot) matches.push(...queryAllDeep(element.shadowRoot, selector))
    }
    return matches
  }
  const selectors = [
    'div.input-editor[contenteditable][data-placeholder="添加描述"]',
    '[contenteditable][data-placeholder*="描述"]',
    '.post-desc-box [contenteditable]'
  ]
  let editor = null
  for (const selector of selectors) {
    const candidates = queryAllDeep(document, selector).filter(element =>
      isVisible(element.closest && element.closest('.post-desc-box') || element)
    )
    if (candidates.length === 1) {
      editor = candidates[0]
      break
    }
  }
  if (!editor) {
    return { ok: false, url: location.href, error: '可见描述编辑器数量不为 1' }
  }

  editor.focus()
  const selection = getSelection()
  const range = document.createRange()
  range.selectNodeContents(editor)
  selection.removeAllRanges()
  selection.addRange(range)
  let inserted = false
  try {
    inserted = document.execCommand('insertText', false, value)
    if (!inserted) inserted = document.execCommand('insertHTML', false, value)
  } catch (error) {
    return { ok: false, url: location.href, error: error.message }
  }
  editor.dispatchEvent(new InputEvent('input', {
    bubbles: true, inputType: 'insertText', data: value
  }))
  editor.dispatchEvent(new Event('change', { bubbles: true }))
  editor.blur()
  const current = normalize(editor.textContent)
  return {
    ok: inserted && current === normalize(value),
    url: location.href,
    error: inserted ? '写入后内容校验不一致' : '富文本写入命令未生效'
  }
}

async function updateStatus(context, status, message, error) {
  const url = bridgeUrl(context, '/status')
  const response = await fetch(url, {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({ status, message, error })
  })
  const body = await readJson(response)
  if (!response.ok || body.code !== 200) {
    throw new Error(body.msg || '发布状态回写失败')
  }
  context.status = status
  context.statusMessage = message || ''
  context.lastError = error || ''
  if (context.platformTabId) {
    await chrome.storage.local.set({ [taskKey(context.taskId)]: context })
  }
  await broadcastStatus(context, status, message, error)
}

async function broadcastStatus(context, status, message, error) {
  const event = {
    type: 'ADMIN_PUBLISH_STATUS',
    payload: {
      taskId: context.taskId,
      platform: context.platform,
      status,
      message,
      error
    }
  }
  if (context.adminTabId) {
    try {
      await chrome.tabs.sendMessage(context.adminTabId, event)
      return
    } catch (ignored) {}
  }
  const tabs = await chrome.tabs.query({})
  await Promise.all(tabs.filter(tab => isAllowedAdmin(tab.url)).map(tab =>
    chrome.tabs.sendMessage(tab.id, event).catch(() => {})
  ))
}

async function fetchBridgeTask(apiBaseUrl, taskId, token) {
  const url = apiBaseUrl + '/office/publish/bridge/task/' + encodeURIComponent(taskId)
    + '?token=' + encodeURIComponent(token)
  const response = await fetch(url, { method: 'GET', cache: 'no-store' })
  const body = await readJson(response)
  if (!response.ok || body.code !== 200 || !body.data) {
    throw new Error(body.msg || '读取发布任务失败')
  }
  return body.data
}

async function readJson(response) {
  try {
    return await response.json()
  } catch (error) {
    return { code: response.status, msg: '服务返回了无法识别的内容' }
  }
}

async function getContextForTab(tabId) {
  const tabEntry = await chrome.storage.local.get(tabKey(tabId))
  const taskId = tabEntry[tabKey(tabId)]
  if (!taskId) return null
  const taskEntry = await chrome.storage.local.get(taskKey(taskId))
  return taskEntry[taskKey(taskId)] || null
}

function bridgeUrl(context, suffix) {
  return context.apiBaseUrl + '/office/publish/bridge/task/' + encodeURIComponent(context.taskId)
    + suffix + '?token=' + encodeURIComponent(context.token)
}

function validatePayload(payload) {
  if (!payload || typeof payload.taskId !== 'string' || typeof payload.token !== 'string'
      || typeof payload.platform !== 'string' || typeof payload.apiBaseUrl !== 'string') {
    throw new Error('发布任务参数不完整')
  }
  if (!PLATFORM_URLS[payload.platform]) throw new Error('不支持的发布平台')
  if (!/^publish_[a-f0-9]{32}$/.test(payload.taskId)) throw new Error('任务编号格式不正确')
  if (!/^[a-f0-9]{32}$/.test(payload.token)) throw new Error('任务凭证格式不正确')
}

function normalizeApiBase(value, senderUrl) {
  const api = new URL(value)
  const sender = new URL(senderUrl)
  if (api.origin !== sender.origin) throw new Error('任务接口必须与后台页面同源')
  return api.origin + api.pathname.replace(/\/$/, '')
}

function isAllowedAdmin(value) {
  if (!value) return false
  try {
    const url = new URL(value)
    const allowedHost = url.hostname === 'feast.yidaima.cn'
      || url.hostname === 'localhost'
      || url.hostname === '127.0.0.1'
    return allowedHost && url.pathname.indexOf('/office/publish') >= 0
  } catch (error) {
    return false
  }
}

function isExpectedPlatformUrl(value, platform) {
  if (!value || !PLATFORM_HOSTS[platform]) return false
  try {
    const hostname = new URL(value).hostname
    return hostname === PLATFORM_HOSTS[platform]
      || (platform === 'xianyu' && hostname === 'www.goofish.pro')
  } catch (error) {
    return false
  }
}

function platformName(platform) {
  return { xiaohongshu: '小红书', douyin: '抖音', wechat_channels: '视频号', bilibili: 'B站', xianyu: '闲鱼' }[platform] || platform
}

function taskKey(taskId) { return 'publisher_task_' + taskId }
function tabKey(tabId) { return 'publisher_tab_' + tabId }
function batchKey(batchId) { return 'publisher_batch_' + batchId }
function batchWatchdogName(batchId) { return BATCH_WATCHDOG_PREFIX + batchId }
function readableError(error) { return error && error.message ? error.message : String(error || '未知错误') }
function sleep(ms) { return new Promise(resolve => setTimeout(resolve, ms)) }