refactor: implement <webview> methods via dedicated IPCs without the remote module (#14377)

lib/browser/rpc-server.js

@@ -373,19 +373,37 @@ handleRemoteCommand('ELECTRON_BROWSER_GUEST_WEB_CONTENTS', function (event, cont
   return valueToMeta(event.sender, contextId, guestViewManager.getGuest(guestInstanceId))
 })
 
-ipcMain.on('ELECTRON_BROWSER_ASYNC_CALL_TO_GUEST_VIEW', function (event, contextId, requestId, guestInstanceId, method, ...args) {
+ipcMain.on('ELECTRON_BROWSER_ASYNC_CALL_TO_GUEST_VIEW', function (event, requestId, guestInstanceId, method, args, hasCallback) {
+  new Promise(resolve => {
+    let guestViewManager = require('./guest-view-manager')
+    let guest = guestViewManager.getGuest(guestInstanceId)
+    if (guest.hostWebContents !== event.sender) {
+      throw new Error('Access denied')
+    }
+    if (hasCallback) {
+      guest[method](...args, resolve)
+    } else {
+      resolve(guest[method](...args))
+    }
+  }).then(result => {
+    return [null, result]
+  }, error => {
+    return [errorUtils.serialize(error)]
+  }).then(responseArgs => {
+    event.sender.send(`ELECTRON_RENDERER_ASYNC_CALL_TO_GUEST_VIEW_RESPONSE_${requestId}`, ...responseArgs)
+  })
+})
+
+ipcMain.on('ELECTRON_BROWSER_SYNC_CALL_TO_GUEST_VIEW', function (event, guestInstanceId, method, args) {
   try {
     let guestViewManager = require('@electron/internal/browser/guest-view-manager')
     let guest = guestViewManager.getGuest(guestInstanceId)
-    if (requestId) {
-      const responseCallback = function (result) {
-        event.sender.send(`ELECTRON_RENDERER_ASYNC_CALL_TO_GUEST_VIEW_RESPONSE_${requestId}`, result)
-      }
-      args.push(responseCallback)
+    if (guest.hostWebContents !== event.sender) {
+      throw new Error('Access denied')
     }
-    guest[method].apply(guest, args)
+    event.returnValue = [null, guest[method].apply(guest, args)]
   } catch (error) {
-    event.returnValue = exceptionToMeta(event.sender, contextId, error)
+    event.returnValue = [errorUtils.serialize(error)]
   }
 })
 

lib/renderer/web-view/web-view-attributes.js

@@ -1,8 +1,9 @@
 'use strict'
 
+const { ipcRenderer } = require('electron')
 const WebViewImpl = require('@electron/internal/renderer/web-view/web-view')
 const webViewConstants = require('@electron/internal/renderer/web-view/web-view-constants')
-const { remote } = require('electron')
+const errorUtils = require('@electron/internal/common/error-utils')
 
 // Helper function to resolve url set in attribute.
 const a = document.createElement('a')
@@ -180,8 +181,15 @@ class SrcAttribute extends WebViewAttribute {
     if (useragent) {
       opts.userAgent = useragent
     }
-    const guestContents = remote.getGuestWebContents(this.webViewImpl.guestInstanceId)
-    guestContents.loadURL(this.getValue(), opts)
+
+    const guestInstanceId = this.webViewImpl.guestInstanceId
+    const method = 'loadURL'
+    const args = [this.getValue(), opts]
+
+    const [error] = ipcRenderer.sendSync('ELECTRON_BROWSER_SYNC_CALL_TO_GUEST_VIEW', guestInstanceId, method, args)
+    if (error) {
+      throw errorUtils.deserialize(error)
+    }
   }
 }
 

lib/renderer/web-view/web-view.js

@@ -5,9 +5,7 @@ const { ipcRenderer, remote, webFrame } = require('electron')
 const v8Util = process.atomBinding('v8_util')
 const guestViewInternal = require('@electron/internal/renderer/web-view/guest-view-internal')
 const webViewConstants = require('@electron/internal/renderer/web-view/web-view-constants')
-
-// An unique ID that can represent current context.
-const contextId = v8Util.getHiddenValue(global, 'contextId')
+const errorUtils = require('@electron/internal/common/error-utils')
 
 // ID generator.
 let nextId = 0
@@ -66,7 +64,6 @@ class WebViewImpl {
       this.guestInstanceId = void 0
     }
 
-    this.webContents = null
     this.beforeFirstNavigation = true
     this.attributes[webViewConstants.ATTRIBUTE_PARTITION].validPartitionId = true
 
@@ -188,7 +185,6 @@ class WebViewImpl {
     }
     this.internalInstanceId = getNextId()
     this.guestInstanceId = guestInstanceId
-    this.webContents = remote.getGuestWebContents(this.guestInstanceId)
     guestViewInternal.attachGuest(this.internalInstanceId, this.guestInstanceId, this.buildParams(), this.internalElement.contentWindow)
     // ResizeObserver is a browser global not recognized by "standard".
     /* globals ResizeObserver */
@@ -277,14 +273,9 @@ const registerWebViewElement = function () {
     'stopFindInPage',
     'downloadURL',
     'inspectServiceWorker',
-    'print',
-    'printToPDF',
     'showDefinitionForSelection',
-    'capturePage',
     'setZoomFactor',
-    'setZoomLevel',
-    'getZoomLevel',
-    'getZoomFactor'
+    'setZoomLevel'
   ]
   const nonblockMethods = [
     'insertCSS',
@@ -292,17 +283,32 @@ const registerWebViewElement = function () {
     'send',
     'sendInputEvent',
     'setLayoutZoomLevelLimits',
-    'setVisualZoomLevelLimits'
+    'setVisualZoomLevelLimits',
+    // with callback
+    'capturePage',
+    'executeJavaScript',
+    'getZoomFactor',
+    'getZoomLevel',
+    'print',
+    'printToPDF'
   ]
 
+  const getGuestInstanceId = function (self) {
+    const internal = v8Util.getHiddenValue(self, 'internal')
+    if (!internal.guestInstanceId) {
+      throw new Error('The WebView must be attached to the DOM and the dom-ready event emitted before this method can be called.')
+    }
+    return internal.guestInstanceId
+  }
+
   // Forward proto.foo* method calls to WebViewImpl.foo*.
-  const createBlockHandler = function (m) {
+  const createBlockHandler = function (method) {
     return function (...args) {
-      const internal = v8Util.getHiddenValue(this, 'internal')
-      if (internal.webContents) {
-        return internal.webContents[m](...args)
+      const [error, result] = ipcRenderer.sendSync('ELECTRON_BROWSER_SYNC_CALL_TO_GUEST_VIEW', getGuestInstanceId(this), method, args)
+      if (error) {
+        throw errorUtils.deserialize(error)
       } else {
-        throw new Error(`Cannot call ${m} because the webContents is unavailable. The WebView must be attached to the DOM and the dom-ready event emitted before this method can be called.`)
+        return result
       }
     }
   }
@@ -310,36 +316,31 @@ const registerWebViewElement = function () {
     proto[method] = createBlockHandler(method)
   }
 
-  const createNonBlockHandler = function (m) {
+  const createNonBlockHandler = function (method) {
     return function (...args) {
-      const internal = v8Util.getHiddenValue(this, 'internal')
-      ipcRenderer.send('ELECTRON_BROWSER_ASYNC_CALL_TO_GUEST_VIEW', contextId, null, internal.guestInstanceId, m, ...args)
+      const callback = (typeof args[args.length - 1] === 'function') ? args.pop() : null
+      const requestId = getNextId()
+      ipcRenderer.once(`ELECTRON_RENDERER_ASYNC_CALL_TO_GUEST_VIEW_RESPONSE_${requestId}`, function (event, error, result) {
+        if (error == null) {
+          if (callback) callback(result)
+        } else {
+          throw errorUtils.deserialize(error)
+        }
+      })
+      ipcRenderer.send('ELECTRON_BROWSER_ASYNC_CALL_TO_GUEST_VIEW', requestId, getGuestInstanceId(this), method, args, callback != null)
     }
   }
   for (const method of nonblockMethods) {
     proto[method] = createNonBlockHandler(method)
   }
 
-  proto.executeJavaScript = function (code, hasUserGesture, callback) {
-    const internal = v8Util.getHiddenValue(this, 'internal')
-    if (typeof hasUserGesture === 'function') {
-      callback = hasUserGesture
-      hasUserGesture = false
-    }
-    const requestId = getNextId()
-    ipcRenderer.send('ELECTRON_BROWSER_ASYNC_CALL_TO_GUEST_VIEW', contextId, requestId, internal.guestInstanceId, 'executeJavaScript', code, hasUserGesture)
-    ipcRenderer.once(`ELECTRON_RENDERER_ASYNC_CALL_TO_GUEST_VIEW_RESPONSE_${requestId}`, function (event, result) {
-      if (callback) callback(result)
-    })
-  }
-
   // WebContents associated with this webview.
   proto.getWebContents = function () {
     const internal = v8Util.getHiddenValue(this, 'internal')
-    if (!internal.webContents) {
+    if (!internal.guestInstanceId) {
       internal.createGuestSync()
     }
-    return internal.webContents
+    return remote.getGuestWebContents(internal.guestInstanceId)
   }
 
   // Focusing the webview should move page focus to the underlying iframe.

spec/webview-spec.js

@@ -890,7 +890,6 @@ describe('<webview> tag', function () {
 
     it('throws a custom error when an API method is called before the event is emitted', () => {
       const expectedErrorMessage =
-          'Cannot call stop because the webContents is unavailable. ' +
           'The WebView must be attached to the DOM ' +
           'and the dom-ready event emitted before this method can be called.'
       expect(() => { webview.stop() }).to.throw(expectedErrorMessage)
@@ -1179,7 +1178,6 @@ describe('<webview> tag', function () {
       loadWebView(webview)
       setTimeout(() => {
         const expectedErrorMessage =
-            'Cannot call stop because the webContents is unavailable. ' +
             'The WebView must be attached to the DOM ' +
             'and the dom-ready event emitted before this method can be called.'
         expect(() => { webview.stop() }).to.throw(expectedErrorMessage)