Move event stuff of web_view.js to its own class/file.

chrome/renderer/resources/extensions/web_view_events.js

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Event management for WebViewInternal.
+
+var DeclarativeWebRequestSchema =
+    requireNative('schema_registry').GetSchema('declarativeWebRequest');
+var EventBindings = require('event_bindings');
+var IdGenerator = requireNative('id_generator');
+var MessagingNatives = requireNative('messaging_natives');
+var WebRequestEvent = require('webRequestInternal').WebRequestEvent;
+var WebRequestSchema =
+    requireNative('schema_registry').GetSchema('webRequest');
+var WebView = require('webview').WebView;
+
+var CreateEvent = function(name) {
+  var eventOpts = {supportsListeners: true, supportsFilters: true};
+  return new EventBindings.Event(name, undefined, eventOpts);
+};
+
+var FrameNameChangedEvent = CreateEvent('webview.onFrameNameChanged');
+var WebRequestMessageEvent = CreateEvent('webview.onMessage');
+
+// WEB_VIEW_EVENTS is a map of stable <webview> DOM event names to their
+//     associated extension event descriptor objects.
+// An event listener will be attached to the extension event |evt| specified in
+//     the descriptor.
+// |fields| specifies the public-facing fields in the DOM event that are
+//     accessible to <webview> developers.
+// |customHandler| allows a handler function to be called each time an extension
+//     event is caught by its event listener. The DOM event should be dispatched
+//     within this handler function. With no handler function, the DOM event
+//     will be dispatched by default each time the extension event is caught.
+// |cancelable| (default: false) specifies whether the event's default
+//     behavior can be canceled. If the default action associated with the event
+//     is prevented, then its dispatch function will return false in its event
+//     handler. The event must have a custom handler for this to be meaningful.
+var WEB_VIEW_EVENTS = {
+  'close': {
+    evt: CreateEvent('webview.onClose'),
+    fields: []
+  },
+  'consolemessage': {
+    evt: CreateEvent('webview.onConsoleMessage'),
+    fields: ['level', 'message', 'line', 'sourceId']
+  },
+  'contentload': {
+    evt: CreateEvent('webview.onContentLoad'),
+    fields: []
+  },
+  'contextmenu': {
+    evt: CreateEvent('webview.contextmenu'),
+    cancelable: true,
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handleContextMenu(event, webViewEvent);
+    },
+    fields: ['items']
+  },
+  'dialog': {
+    cancelable: true,
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handleDialogEvent(event, webViewEvent);
+    },
+    evt: CreateEvent('webview.onDialog'),
+    fields: ['defaultPromptText', 'messageText', 'messageType', 'url']
+  },
+  'exit': {
+     evt: CreateEvent('webview.onExit'),
+     fields: ['processId', 'reason']
+  },
+  'loadabort': {
+    cancelable: true,
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handleLoadAbortEvent(event, webViewEvent);
+    },
+    evt: CreateEvent('webview.onLoadAbort'),
+    fields: ['url', 'isTopLevel', 'reason']
+  },
+  'loadcommit': {
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handleLoadCommitEvent(event, webViewEvent);
+    },
+    evt: CreateEvent('webview.onLoadCommit'),
+    fields: ['url', 'isTopLevel']
+  },
+  'loadprogress': {
+    evt: CreateEvent('webview.onLoadProgress'),
+    fields: ['url', 'progress']
+  },
+  'loadredirect': {
+    evt: CreateEvent('webview.onLoadRedirect'),
+    fields: ['isTopLevel', 'oldUrl', 'newUrl']
+  },
+  'loadstart': {
+    evt: CreateEvent('webview.onLoadStart'),
+    fields: ['url', 'isTopLevel']
+  },
+  'loadstop': {
+    evt: CreateEvent('webview.onLoadStop'),
+    fields: []
+  },
+  'newwindow': {
+    cancelable: true,
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handleNewWindowEvent(event, webViewEvent);
+    },
+    evt: CreateEvent('webview.onNewWindow'),
+    fields: [
+      'initialHeight',
+      'initialWidth',
+      'targetUrl',
+      'windowOpenDisposition',
+      'name'
+    ]
+  },
+  'permissionrequest': {
+    cancelable: true,
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handlePermissionEvent(event, webViewEvent);
+    },
+    evt: CreateEvent('webview.onPermissionRequest'),
+    fields: [
+      'identifier',
+      'lastUnlockedBySelf',
+      'name',
+      'permission',
+      'requestMethod',
+      'url',
+      'userGesture'
+    ]
+  },
+  'responsive': {
+    evt: CreateEvent('webview.onResponsive'),
+    fields: ['processId']
+  },
+  'sizechanged': {
+    evt: CreateEvent('webview.onSizeChanged'),
+    customHandler: function(handler, event, webViewEvent) {
+      handler.handleSizeChangedEvent(event, webViewEvent);
+    },
+    fields: ['oldHeight', 'oldWidth', 'newHeight', 'newWidth']
+  },
+  'unresponsive': {
+    evt: CreateEvent('webview.onUnresponsive'),
+    fields: ['processId']
+  }
+};
+
+function DeclarativeWebRequestEvent(opt_eventName,
+                                    opt_argSchemas,
+                                    opt_eventOptions,
+                                    opt_webViewInstanceId) {
+  var subEventName = opt_eventName + '/' + IdGenerator.GetNextId();
+  EventBindings.Event.call(this, subEventName, opt_argSchemas, opt_eventOptions,
+      opt_webViewInstanceId);
+
+  var self = this;
+  // TODO(lazyboy): When do we dispose this listener?
+  WebRequestMessageEvent.addListener(function() {
+    // Re-dispatch to subEvent's listeners.
+    $Function.apply(self.dispatch, self, $Array.slice(arguments));
+  }, {instanceId: opt_webViewInstanceId || 0});
+}
+
+DeclarativeWebRequestEvent.prototype = {
+  __proto__: EventBindings.Event.prototype
+};
+
+// Constructor.
+function WebViewEvents(webViewInternal, viewInstanceId) {
+  this.webViewInternal = webViewInternal;
+  this.viewInstanceId = viewInstanceId;
+  this.setup();
+}
+
+// Sets up events.
+WebViewEvents.prototype.setup = function() {
+  this.setupFrameNameChangedEvent();
+  this.setupWebRequestEvents();
+  this.webViewInternal.setupExperimentalContextMenus();
+
+  var events = this.getEvents();
+  for (var eventName in events) {
+    this.setupEvent(eventName, events[eventName]);
+  }
+};
+
+WebViewEvents.prototype.setupFrameNameChangedEvent = function() {
+  var self = this;
+  FrameNameChangedEvent.addListener(function(e) {
+    self.webViewInternal.onFrameNameChanged(e.name);
+  }, {instanceId: self.viewInstanceId});
+};
+
+WebViewEvents.prototype.setupWebRequestEvents = function() {
+  var self = this;
+  var request = {};
+  var createWebRequestEvent = function(webRequestEvent) {
+    return function() {
+      if (!self[webRequestEvent.name]) {
+        self[webRequestEvent.name] =
+            new WebRequestEvent(
+                'webview.' + webRequestEvent.name,
+                webRequestEvent.parameters,
+                webRequestEvent.extraParameters, webRequestEvent.options,
+                self.viewInstanceId);
+      }
+      return self[webRequestEvent.name];
+    };
+  };
+
+  var createDeclarativeWebRequestEvent = function(webRequestEvent) {
+    return function() {
+      if (!self[webRequestEvent.name]) {
+        // The onMessage event gets a special event type because we want
+        // the listener to fire only for messages targeted for this particular
+        // <webview>.
+        var EventClass = webRequestEvent.name === 'onMessage' ?
+            DeclarativeWebRequestEvent : EventBindings.Event;
+        self[webRequestEvent.name] =
+            new EventClass(
+                'webview.' + webRequestEvent.name,
+                webRequestEvent.parameters,
+                webRequestEvent.options,
+                self.viewInstanceId);
+      }
+      return self[webRequestEvent.name];
+    };
+  };
+
+  for (var i = 0; i < DeclarativeWebRequestSchema.events.length; ++i) {
+    var eventSchema = DeclarativeWebRequestSchema.events[i];
+    var webRequestEvent = createDeclarativeWebRequestEvent(eventSchema);
+    Object.defineProperty(
+        request,
+        eventSchema.name,
+        {
+          get: webRequestEvent,
+          enumerable: true
+        }
+    );
+  }
+
+  // Populate the WebRequest events from the API definition.
+  for (var i = 0; i < WebRequestSchema.events.length; ++i) {
+    var webRequestEvent = createWebRequestEvent(WebRequestSchema.events[i]);
+    Object.defineProperty(
+        request,
+        WebRequestSchema.events[i].name,
+        {
+          get: webRequestEvent,
+          enumerable: true
+        }
+    );
+  }
+
+  this.webViewInternal.setRequestPropertyOnWebViewNode(request);
+};
+
+WebViewEvents.prototype.getEvents = function() {
+  var experimentalEvents = this.webViewInternal.maybeGetExperimentalEvents();
+  for (var eventName in experimentalEvents) {
+    WEB_VIEW_EVENTS[eventName] = experimentalEvents[eventName];
+  }
+  return WEB_VIEW_EVENTS;
+};
+
+WebViewEvents.prototype.setupEvent = function(name, info) {
+  var self = this;
+  info.evt.addListener(function(e) {
+    var details = {bubbles:true};
+    if (info.cancelable)
+      details.cancelable = true;
+    var webViewEvent = new Event(name, details);
+    $Array.forEach(info.fields, function(field) {
+      if (e[field] !== undefined) {
+        webViewEvent[field] = e[field];
+      }
+    });
+    if (info.customHandler) {
+      info.customHandler(self, e, webViewEvent);
+      return;
+    }
+    self.webViewInternal.dispatchEvent(webViewEvent);
+  }, {instanceId: self.viewInstanceId});
+
+  this.webViewInternal.setupEventProperty(name);
+};
+
+
+// Event handlers.
+WebViewEvents.prototype.handleContextMenu = function(e, webViewEvent) {
+  this.webViewInternal.maybeHandleContextMenu();
+};
+
+WebViewEvents.prototype.handleDialogEvent = function(event, webViewEvent) {
+  var showWarningMessage = function(dialogType) {
+    var VOWELS = ['a', 'e', 'i', 'o', 'u'];
+    var WARNING_MSG_DIALOG_BLOCKED = '<webview>: %1 %2 dialog was blocked.';
+    var article = (VOWELS.indexOf(dialogType.charAt(0)) >= 0) ? 'An' : 'A';
+    var output = WARNING_MSG_DIALOG_BLOCKED.replace('%1', article);
+    output = output.replace('%2', dialogType);
+    window.console.warn(output);
+  };
+
+  var self = this;
+  var requestId = event.requestId;
+  var actionTaken = false;
+
+  var validateCall = function() {
+    var ERROR_MSG_DIALOG_ACTION_ALREADY_TAKEN = '<webview>: ' +
+        'An action has already been taken for this "dialog" event.';
+
+    if (actionTaken) {
+      throw new Error(ERROR_MSG_DIALOG_ACTION_ALREADY_TAKEN);
+    }
+    actionTaken = true;
+  };
+
+  var getInstanceId = function() {
+    return self.webViewInternal.getInstanceId();
+  };
+
+  var dialog = {
+    ok: function(user_input) {
+      validateCall();
+      user_input = user_input || '';
+      WebView.setPermission(getInstanceId(), requestId, 'allow', user_input);
+    },
+    cancel: function() {
+      validateCall();
+      WebView.setPermission(getInstanceId(), requestId, 'deny');
+    }
+  };
+  webViewEvent.dialog = dialog;
+
+  var defaultPrevented = !self.webViewInternal.dispatchEvent(webViewEvent);
+  if (actionTaken) {
+    return;
+  }
+
+  if (defaultPrevented) {
+    // Tell the JavaScript garbage collector to track lifetime of |dialog| and
+    // call back when the dialog object has been collected.
+    MessagingNatives.BindToGC(dialog, function() {
+      // Avoid showing a warning message if the decision has already been made.
+      if (actionTaken) {
+        return;
+      }
+      WebView.setPermission(
+          getInstanceId(), requestId, 'default', '', function(allowed) {
+        if (allowed) {
+          return;
+        }
+        showWarningMessage(event.messageType);
+      });
+    });
+  } else {
+    actionTaken = true;
+    // The default action is equivalent to canceling the dialog.
+    WebView.setPermission(
+        getInstanceId(), requestId, 'default', '', function(allowed) {
+      if (allowed) {
+        return;
+      }
+      showWarningMessage(event.messageType);
+    });
+  }
+};
+
+WebViewEvents.prototype.handleLoadAbortEvent = function(event, webViewEvent) {
+  var showWarningMessage = function(reason) {
+    var WARNING_MSG_LOAD_ABORTED = '<webview>: ' +
+        'The load has aborted with reason "%1".';
+    window.console.warn(WARNING_MSG_LOAD_ABORTED.replace('%1', reason));
+  };
+  if (this.webViewInternal.dispatchEvent(webViewEvent)) {
+    showWarningMessage(event.reason);
+  }
+};
+
+WebViewEvents.prototype.handleLoadCommitEvent = function(event, webViewEvent) {
+  this.webViewInternal.onLoadCommit(event.currentEntryIndex, event.entryCount,
+                                    event.processId, event.url,
+                                    event.isTopLevel);
+  this.webViewInternal.dispatchEvent(webViewEvent);
+};
+
+WebViewEvents.prototype.handleNewWindowEvent = function(event, webViewEvent) {
+  var ERROR_MSG_NEWWINDOW_ACTION_ALREADY_TAKEN = '<webview>: ' +
+      'An action has already been taken for this "newwindow" event.';
+
+  var ERROR_MSG_NEWWINDOW_UNABLE_TO_ATTACH = '<webview>: ' +
+      'Unable to attach the new window to the provided webview.';
+
+  var ERROR_MSG_WEBVIEW_EXPECTED = '<webview> element expected.';
+
+  var showWarningMessage = function() {
+    var WARNING_MSG_NEWWINDOW_BLOCKED = '<webview>: A new window was blocked.';
+    window.console.warn(WARNING_MSG_NEWWINDOW_BLOCKED);
+  };
+
+  var requestId = event.requestId;
+  var actionTaken = false;
+  var self = this;
+  var getInstanceId = function() {
+    return self.webViewInternal.getInstanceId();
+  };
+
+  var validateCall = function () {
+    if (actionTaken) {
+      throw new Error(ERROR_MSG_NEWWINDOW_ACTION_ALREADY_TAKEN);
+    }
+    actionTaken = true;
+  };
+
+  var windowObj = {
+    attach: function(webview) {
+      validateCall();
+      if (!webview || !webview.tagName || webview.tagName != 'WEBVIEW')
+        throw new Error(ERROR_MSG_WEBVIEW_EXPECTED);
+      // Attach happens asynchronously to give the tagWatcher an opportunity
+      // to pick up the new webview before attach operates on it, if it hasn't
+      // been attached to the DOM already.
+      // Note: Any subsequent errors cannot be exceptions because they happen
+      // asynchronously.
+      setTimeout(function() {
+        var webViewInternal = privates(webview).internal;
+        if (event.storagePartitionId) {
+          webViewInternal.onAttach(event.storagePartitionId);
+        }
+
+        var attached =
+            webViewInternal.attachWindowAndSetUpEvents(
+                event.windowId, undefined, event.storagePartitionId);
+
+        if (!attached) {
+          window.console.error(ERROR_MSG_NEWWINDOW_UNABLE_TO_ATTACH);
+        }
+        // If the object being passed into attach is not a valid <webview>
+        // then we will fail and it will be treated as if the new window
+        // was rejected. The permission API plumbing is used here to clean
+        // up the state created for the new window if attaching fails.
+        WebView.setPermission(
+            getInstanceId(), requestId, attached ? 'allow' : 'deny');
+      }, 0);
+    },
+    discard: function() {
+      validateCall();
+      WebView.setPermission(getInstanceId(), requestId, 'deny');
+    }
+  };
+  webViewEvent.window = windowObj;
+
+  var defaultPrevented = !self.webViewInternal.dispatchEvent(webViewEvent);
+  if (actionTaken) {
+    return;
+  }
+
+  if (defaultPrevented) {
+    // Make browser plugin track lifetime of |windowObj|.
+    MessagingNatives.BindToGC(windowObj, function() {
+      // Avoid showing a warning message if the decision has already been made.
+      if (actionTaken) {
+        return;
+      }
+      WebView.setPermission(
+          getInstanceId(), requestId, 'default', '', function(allowed) {
+        if (allowed) {
+          return;
+        }
+        showWarningMessage();
+      });
+    });
+  } else {
+    actionTaken = true;
+    // The default action is to discard the window.
+    WebView.setPermission(
+        getInstanceId(), requestId, 'default', '', function(allowed) {
+      if (allowed) {
+        return;
+      }
+      showWarningMessage();
+    });
+  }
+};
+
+WebViewEvents.prototype.getPermissionTypes = function() {
+  var permissions =
+      ['media',
+      'geolocation',
+      'pointerLock',
+      'download',
+      'loadplugin',
+      'filesystem'];
+  return permissions.concat(
+      this.webViewInternal.maybeGetExperimentalPermissions());
+};
+
+WebViewEvents.prototype.handlePermissionEvent =
+    function(event, webViewEvent) {
+  var ERROR_MSG_PERMISSION_ALREADY_DECIDED = '<webview>: ' +
+      'Permission has already been decided for this "permissionrequest" event.';
+
+  var showWarningMessage = function(permission) {
+    var WARNING_MSG_PERMISSION_DENIED = '<webview>: ' +
+        'The permission request for "%1" has been denied.';
+    window.console.warn(
+        WARNING_MSG_PERMISSION_DENIED.replace('%1', permission));
+  };
+
+  var requestId = event.requestId;
+  var self = this;
+  var getInstanceId = function() {
+    return self.webViewInternal.getInstanceId();
+  };
+
+  if (this.getPermissionTypes().indexOf(event.permission) < 0) {
+    // The permission type is not allowed. Trigger the default response.
+    WebView.setPermission(
+        getInstanceId(), requestId, 'default', '', function(allowed) {
+      if (allowed) {
+        return;
+      }
+      showWarningMessage(event.permission);
+    });
+    return;
+  }
+
+  var decisionMade = false;
+  var validateCall = function() {
+    if (decisionMade) {
+      throw new Error(ERROR_MSG_PERMISSION_ALREADY_DECIDED);
+    }
+    decisionMade = true;
+  };
+
+  // Construct the event.request object.
+  var request = {
+    allow: function() {
+      validateCall();
+      WebView.setPermission(getInstanceId(), requestId, 'allow');
+    },
+    deny: function() {
+      validateCall();
+      WebView.setPermission(getInstanceId(), requestId, 'deny');
+    }
+  };
+  webViewEvent.request = request;
+
+  var defaultPrevented = !self.webViewInternal.dispatchEvent(webViewEvent);
+  if (decisionMade) {
+    return;
+  }
+
+  if (defaultPrevented) {
+    // Make browser plugin track lifetime of |request|.
+    MessagingNatives.BindToGC(request, function() {
+      // Avoid showing a warning message if the decision has already been made.
+      if (decisionMade) {
+        return;
+      }
+      WebView.setPermission(
+          getInstanceId(), requestId, 'default', '', function(allowed) {
+        if (allowed) {
+          return;
+        }
+        showWarningMessage(event.permission);
+      });
+    });
+  } else {
+    decisionMade = true;
+    WebView.setPermission(
+        getInstanceId(), requestId, 'default', '', function(allowed) {
+      if (allowed) {
+        return;
+      }
+      showWarningMessage(event.permission);
+    });
+  }
+};
+
+WebViewEvents.prototype.handleSizeChangedEvent = function(
+    event, webViewEvent) {
+  this.webViewInternal.onSizeChanged(webViewEvent.newWidth,
+                                     webViewEvent.newHeight);
+  this.webViewInternal.dispatchEvent(webViewEvent);
+};
+
+exports.WebViewEvents = WebViewEvents;
+exports.CreateEvent = CreateEvent;