feat: add Chrome extension browser relay

2026-01-15 04:50:11 +00:00
parent 5fdaef3646
commit ef78b198cb
40 changed files with 2467 additions and 49 deletions
--- a/assets/chrome-extension/background.js
+++ b/assets/chrome-extension/background.js
@@ -0,0 +1,407 @@
+const DEFAULT_PORT = 18792
+
+const BADGE = {
+  on: { text: 'ON', color: '#0B6E4F' },
+  off: { text: '', color: '#000000' },
+  connecting: { text: '…', color: '#B45309' },
+  error: { text: '!', color: '#B91C1C' },
+}
+
+/** @type {WebSocket|null} */
+let relayWs = null
+/** @type {Promise<void>|null} */
+let relayConnectPromise = null
+
+let debuggerListenersInstalled = false
+
+let nextSession = 1
+
+/** @type {Map<number, {state:'connecting'|'connected', sessionId?:string, targetId?:string, attachOrder?:number}>} */
+const tabs = new Map()
+/** @type {Map<string, number>} */
+const tabBySession = new Map()
+/** @type {Map<string, number>} */
+const childSessionToTab = new Map()
+
+/** @type {Map<number, {resolve:(v:any)=>void, reject:(e:Error)=>void}>} */
+const pending = new Map()
+
+function nowStack() {
+  try {
+    return new Error().stack || ''
+  } catch {
+    return ''
+  }
+}
+
+async function getRelayPort() {
+  const stored = await chrome.storage.local.get(['relayPort'])
+  const raw = stored.relayPort
+  const n = Number.parseInt(String(raw || ''), 10)
+  if (!Number.isFinite(n) || n <= 0 || n > 65535) return DEFAULT_PORT
+  return n
+}
+
+function setBadge(tabId, kind) {
+  const cfg = BADGE[kind]
+  void chrome.action.setBadgeText({ tabId, text: cfg.text })
+  void chrome.action.setBadgeBackgroundColor({ tabId, color: cfg.color })
+}
+
+async function ensureRelayConnection() {
+  if (relayWs && relayWs.readyState === WebSocket.OPEN) return
+  if (relayConnectPromise) return await relayConnectPromise
+
+  relayConnectPromise = (async () => {
+    const port = await getRelayPort()
+    const httpBase = `http://127.0.0.1:${port}`
+    const wsUrl = `ws://127.0.0.1:${port}/extension`
+
+    // Fast preflight: is the relay server up?
+    try {
+      await fetch(`${httpBase}/`, { method: 'HEAD', signal: AbortSignal.timeout(2000) })
+    } catch (err) {
+      throw new Error(`Relay server not reachable at ${httpBase} (${String(err)})`)
+    }
+
+    const ws = new WebSocket(wsUrl)
+    relayWs = ws
+
+    await new Promise((resolve, reject) => {
+      const t = setTimeout(() => reject(new Error('WebSocket connect timeout')), 5000)
+      ws.onopen = () => {
+        clearTimeout(t)
+        resolve()
+      }
+      ws.onerror = () => {
+        clearTimeout(t)
+        reject(new Error('WebSocket connect failed'))
+      }
+      ws.onclose = (ev) => {
+        clearTimeout(t)
+        reject(new Error(`WebSocket closed (${ev.code} ${ev.reason || 'no reason'})`))
+      }
+    })
+
+    ws.onmessage = (event) => void onRelayMessage(String(event.data || ''))
+    ws.onclose = () => onRelayClosed('closed')
+    ws.onerror = () => onRelayClosed('error')
+
+    if (!debuggerListenersInstalled) {
+      debuggerListenersInstalled = true
+      chrome.debugger.onEvent.addListener(onDebuggerEvent)
+      chrome.debugger.onDetach.addListener(onDebuggerDetach)
+    }
+  })()
+
+  try {
+    await relayConnectPromise
+  } finally {
+    relayConnectPromise = null
+  }
+}
+
+function onRelayClosed(reason) {
+  relayWs = null
+  for (const [id, p] of pending.entries()) {
+    pending.delete(id)
+    p.reject(new Error(`Relay disconnected (${reason})`))
+  }
+
+  for (const tabId of tabs.keys()) {
+    void chrome.debugger.detach({ tabId }).catch(() => {})
+    setBadge(tabId, 'connecting')
+  }
+  tabs.clear()
+  tabBySession.clear()
+  childSessionToTab.clear()
+}
+
+function sendToRelay(payload) {
+  const ws = relayWs
+  if (!ws || ws.readyState !== WebSocket.OPEN) {
+    throw new Error('Relay not connected')
+  }
+  ws.send(JSON.stringify(payload))
+}
+
+function requestFromRelay(command) {
+  const id = command.id
+  return new Promise((resolve, reject) => {
+    pending.set(id, { resolve, reject })
+    try {
+      sendToRelay(command)
+    } catch (err) {
+      pending.delete(id)
+      reject(err instanceof Error ? err : new Error(String(err)))
+    }
+  })
+}
+
+async function onRelayMessage(text) {
+  /** @type {any} */
+  let msg
+  try {
+    msg = JSON.parse(text)
+  } catch {
+    return
+  }
+
+  if (msg && msg.method === 'ping') {
+    try {
+      sendToRelay({ method: 'pong' })
+    } catch {
+      // ignore
+    }
+    return
+  }
+
+  if (msg && typeof msg.id === 'number' && (msg.result !== undefined || msg.error !== undefined)) {
+    const p = pending.get(msg.id)
+    if (!p) return
+    pending.delete(msg.id)
+    if (msg.error) p.reject(new Error(String(msg.error)))
+    else p.resolve(msg.result)
+    return
+  }
+
+  if (msg && typeof msg.id === 'number' && msg.method === 'forwardCDPCommand') {
+    try {
+      const result = await handleForwardCdpCommand(msg)
+      sendToRelay({ id: msg.id, result })
+    } catch (err) {
+      sendToRelay({ id: msg.id, error: err instanceof Error ? err.message : String(err) })
+    }
+  }
+}
+
+function getTabBySessionId(sessionId) {
+  const direct = tabBySession.get(sessionId)
+  if (direct) return { tabId: direct, kind: 'main' }
+  const child = childSessionToTab.get(sessionId)
+  if (child) return { tabId: child, kind: 'child' }
+  return null
+}
+
+function getTabByTargetId(targetId) {
+  for (const [tabId, tab] of tabs.entries()) {
+    if (tab.targetId === targetId) return tabId
+  }
+  return null
+}
+
+async function attachTab(tabId, opts = {}) {
+  const debuggee = { tabId }
+  await chrome.debugger.attach(debuggee, '1.3')
+  await chrome.debugger.sendCommand(debuggee, 'Page.enable').catch(() => {})
+
+  const info = /** @type {any} */ (await chrome.debugger.sendCommand(debuggee, 'Target.getTargetInfo'))
+  const targetInfo = info?.targetInfo
+  const targetId = String(targetInfo?.targetId || '').trim()
+  if (!targetId) {
+    throw new Error('Target.getTargetInfo returned no targetId')
+  }
+
+  const sessionId = `cb-tab-${nextSession++}`
+  const attachOrder = nextSession
+
+  tabs.set(tabId, { state: 'connected', sessionId, targetId, attachOrder })
+  tabBySession.set(sessionId, tabId)
+
+  if (!opts.skipAttachedEvent) {
+    sendToRelay({
+      method: 'forwardCDPEvent',
+      params: {
+        method: 'Target.attachedToTarget',
+        params: {
+          sessionId,
+          targetInfo: { ...targetInfo, attached: true },
+          waitingForDebugger: false,
+        },
+      },
+    })
+  }
+
+  setBadge(tabId, 'on')
+  return { sessionId, targetId }
+}
+
+async function detachTab(tabId, reason) {
+  const tab = tabs.get(tabId)
+  if (tab?.sessionId && tab?.targetId) {
+    try {
+      sendToRelay({
+        method: 'forwardCDPEvent',
+        params: {
+          method: 'Target.detachedFromTarget',
+          params: { sessionId: tab.sessionId, targetId: tab.targetId, reason },
+        },
+      })
+    } catch {
+      // ignore
+    }
+  }
+
+  if (tab?.sessionId) tabBySession.delete(tab.sessionId)
+  tabs.delete(tabId)
+
+  for (const [childSessionId, parentTabId] of childSessionToTab.entries()) {
+    if (parentTabId === tabId) childSessionToTab.delete(childSessionId)
+  }
+
+  try {
+    await chrome.debugger.detach({ tabId })
+  } catch {
+    // ignore
+  }
+
+  setBadge(tabId, 'off')
+}
+
+async function connectOrToggleForActiveTab() {
+  const [active] = await chrome.tabs.query({ active: true, currentWindow: true })
+  const tabId = active?.id
+  if (!tabId) return
+
+  const existing = tabs.get(tabId)
+  if (existing?.state === 'connected') {
+    await detachTab(tabId, 'toggle')
+    return
+  }
+
+  tabs.set(tabId, { state: 'connecting' })
+  setBadge(tabId, 'connecting')
+
+  try {
+    await ensureRelayConnection()
+    await attachTab(tabId)
+  } catch (err) {
+    tabs.delete(tabId)
+    setBadge(tabId, 'error')
+    const message = err instanceof Error ? err.message : String(err)
+    // Service worker: best-effort surface via title.
+    void chrome.action.setTitle({ tabId, title: `Clawdbot: ${message}` })
+    // Extra breadcrumbs in chrome://extensions service worker logs.
+    console.warn('attach failed', message, nowStack())
+  }
+}
+
+async function handleForwardCdpCommand(msg) {
+  const method = String(msg?.params?.method || '').trim()
+  const params = msg?.params?.params || undefined
+  const sessionId = typeof msg?.params?.sessionId === 'string' ? msg.params.sessionId : undefined
+
+  // Map command to tab
+  const bySession = sessionId ? getTabBySessionId(sessionId) : null
+  const targetId = typeof params?.targetId === 'string' ? params.targetId : undefined
+  const tabId =
+    bySession?.tabId ||
+    (targetId ? getTabByTargetId(targetId) : null) ||
+    (() => {
+      // No sessionId: pick the first connected tab (stable-ish).
+      for (const [id, tab] of tabs.entries()) {
+        if (tab.state === 'connected') return id
+      }
+      return null
+    })()
+
+  if (!tabId) throw new Error(`No attached tab for method ${method}`)
+
+  /** @type {chrome.debugger.DebuggerSession} */
+  const debuggee = { tabId }
+
+  if (method === 'Runtime.enable') {
+    try {
+      await chrome.debugger.sendCommand(debuggee, 'Runtime.disable')
+      await new Promise((r) => setTimeout(r, 50))
+    } catch {
+      // ignore
+    }
+    return await chrome.debugger.sendCommand(debuggee, 'Runtime.enable', params)
+  }
+
+  if (method === 'Target.createTarget') {
+    const url = typeof params?.url === 'string' ? params.url : 'about:blank'
+    const tab = await chrome.tabs.create({ url, active: false })
+    if (!tab.id) throw new Error('Failed to create tab')
+    await new Promise((r) => setTimeout(r, 100))
+    const attached = await attachTab(tab.id)
+    return { targetId: attached.targetId }
+  }
+
+  if (method === 'Target.closeTarget') {
+    const target = typeof params?.targetId === 'string' ? params.targetId : ''
+    const toClose = target ? getTabByTargetId(target) : tabId
+    if (!toClose) return { success: false }
+    try {
+      await chrome.tabs.remove(toClose)
+    } catch {
+      return { success: false }
+    }
+    return { success: true }
+  }
+
+  if (method === 'Target.activateTarget') {
+    const target = typeof params?.targetId === 'string' ? params.targetId : ''
+    const toActivate = target ? getTabByTargetId(target) : tabId
+    if (!toActivate) return {}
+    const tab = await chrome.tabs.get(toActivate).catch(() => null)
+    if (!tab) return {}
+    if (tab.windowId) {
+      await chrome.windows.update(tab.windowId, { focused: true }).catch(() => {})
+    }
+    await chrome.tabs.update(toActivate, { active: true }).catch(() => {})
+    return {}
+  }
+
+  const tabState = tabs.get(tabId)
+  const mainSessionId = tabState?.sessionId
+  const debuggerSession =
+    sessionId && mainSessionId && sessionId !== mainSessionId
+      ? { ...debuggee, sessionId }
+      : debuggee
+
+  return await chrome.debugger.sendCommand(debuggerSession, method, params)
+}
+
+function onDebuggerEvent(source, method, params) {
+  const tabId = source.tabId
+  if (!tabId) return
+  const tab = tabs.get(tabId)
+  if (!tab?.sessionId) return
+
+  if (method === 'Target.attachedToTarget' && params?.sessionId) {
+    childSessionToTab.set(String(params.sessionId), tabId)
+  }
+
+  if (method === 'Target.detachedFromTarget' && params?.sessionId) {
+    childSessionToTab.delete(String(params.sessionId))
+  }
+
+  try {
+    sendToRelay({
+      method: 'forwardCDPEvent',
+      params: {
+        sessionId: source.sessionId || tab.sessionId,
+        method,
+        params,
+      },
+    })
+  } catch {
+    // ignore
+  }
+}
+
+function onDebuggerDetach(source, reason) {
+  const tabId = source.tabId
+  if (!tabId) return
+  if (!tabs.has(tabId)) return
+  void detachTab(tabId, reason)
+}
+
+chrome.action.onClicked.addListener(() => void connectOrToggleForActiveTab())
+
+chrome.runtime.onInstalled.addListener(() => {
+  // Useful: first-time instructions.
+  void chrome.runtime.openOptionsPage()
+})