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Refactor widget postMessage API.

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This commit is contained in:
Richard Lewis 2018-03-28 12:22:06 +01:00
parent 74628120bf
commit 4ac9653ab9
6 changed files with 386 additions and 336 deletions
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201
src/FromWidgetPostMessageApi.js Normal file
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@ -0,0 +1,201 @@
/*
Copyright 2018 New Vector Ltd
Licensed under the Apache License, Version 2.0 (the 'License');
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an 'AS IS' BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
import URL from 'url';
import dis from './dispatcher';
import IntegrationManager from './IntegrationManager';
import WidgetMessagingEndpoint from './WidgetMessagingEndpoint';
const WIDGET_API_VERSION = '0.0.1'; // Current API version
const SUPPORTED_WIDGET_API_VERSIONS = [
'0.0.1',
];
const INBOUND_API_NAME = 'fromWidget';
// Listen for and handle incomming requests using the 'fromWidget' postMessage
// API and initiate responses
export default class FromWidgetPostMessageApi {
constructor() {
this.widgetMessagingEndpoints = [];
this.start = this.start.bind(this);
this.stop = this.stop.bind(this);
this.onPostMessage = this.onPostMessage.bind(this);
}
start() {
window.addEventListener('message', this.onPostMessage);
}
stop() {
window.removeEventListener('message', this.onPostMessage);
}
/**
* Register a widget endpoint for trusted postMessage communication
* @param {string} widgetId Unique widget identifier
* @param {string} endpointUrl Widget wurl origin (protocol + (optional port) + host)
*/
addEndpoint(widgetId, endpointUrl) {
const u = URL.parse(endpointUrl);
if (!u || !u.protocol || !u.host) {
console.warn('Add FromWidgetPostMessageApi endpoint - Invalid origin:', endpointUrl);
return;
}
const origin = u.protocol + '//' + u.host;
const endpoint = new WidgetMessagingEndpoint(widgetId, origin);
if (this.widgetMessagingEndpoints.some(function(ep) {
return (ep.widgetId === widgetId && ep.endpointUrl === endpointUrl);
})) {
// Message endpoint already registered
console.warn('Add FromWidgetPostMessageApi - Endpoint already registered');
return;
} else {
console.warn(`Adding fromWidget messaging endpoint for ${widgetId}`, endpoint);
this.widgetMessagingEndpoints.push(endpoint);
}
}
/**
* De-register a widget endpoint from trusted communication sources
* @param {string} widgetId Unique widget identifier
* @param {string} endpointUrl Widget wurl origin (protocol + (optional port) + host)
* @return {boolean} True if endpoint was successfully removed
*/
removeEndpoint(widgetId, endpointUrl) {
const u = URL.parse(endpointUrl);
if (!u || !u.protocol || !u.host) {
console.warn('Remove widget messaging endpoint - Invalid origin');
return;
}
const origin = u.protocol + '//' + u.host;
if (this.widgetMessagingEndpoints && this.widgetMessagingEndpoints.length > 0) {
const length = this.widgetMessagingEndpoints.length;
this.widgetMessagingEndpoints = this.widgetMessagingEndpoints.
filter(function(endpoint) {
return (endpoint.widgetId != widgetId || endpoint.endpointUrl != origin);
});
return (length > this.widgetMessagingEndpoints.length);
}
return false;
}
/**
* Handle widget postMessage events
* Messages are only handled where a valid, registered messaging endpoints
* @param {Event} event Event to handle
* @return {undefined}
*/
onPostMessage(event) {
if (!event.origin) { // Handle chrome
event.origin = event.originalEvent.origin;
}
// Event origin is empty string if undefined
if (
event.origin.length === 0 ||
!this.trustedEndpoint(event.origin) ||
event.data.api !== INBOUND_API_NAME ||
!event.data.widgetId
) {
return; // don't log this - debugging APIs like to spam postMessage which floods the log otherwise
}
const action = event.data.action;
const widgetId = event.data.widgetId;
if (action === 'content_loaded') {
console.warn('Widget reported content loaded for', widgetId);
dis.dispatch({
action: 'widget_content_loaded',
widgetId: widgetId,
});
this.sendResponse(event, {success: true});
} else if (action === 'supported_api_versions') {
this.sendResponse(event, {
api: INBOUND_API_NAME,
supported_versions: SUPPORTED_WIDGET_API_VERSIONS,
});
} else if (action === 'api_version') {
this.sendResponse(event, {
api: INBOUND_API_NAME,
version: WIDGET_API_VERSION,
});
} else if (action === 'm.sticker') {
// console.warn('Got sticker message from widget', widgetId);
dis.dispatch({action: 'm.sticker', data: event.data.widgetData, widgetId: event.data.widgetId});
} else if (action === 'integration_manager_open') {
// Close the stickerpicker
dis.dispatch({action: 'stickerpicker_close'});
// Open the integration manager
const data = event.data.widgetData;
const integType = (data && data.integType) ? data.integType : null;
const integId = (data && data.integId) ? data.integId : null;
IntegrationManager.open(integType, integId);
} else {
console.warn('Widget postMessage event unhandled');
this.sendError(event, {message: 'The postMessage was unhandled'});
}
}
/**
* Check if message origin is registered as trusted
* @param {string} origin PostMessage origin to check
* @return {boolean} True if trusted
*/
trustedEndpoint(origin) {
if (!origin) {
return false;
}
return this.widgetMessagingEndpoints.some((endpoint) => {
// TODO / FIXME -- Should this also check the widgetId?
return endpoint.endpointUrl === origin;
});
}
/**
* Send a postmessage response to a postMessage request
* @param {Event} event The original postMessage request event
* @param {Object} res Response data
*/
sendResponse(event, res) {
const data = JSON.parse(JSON.stringify(event.data));
data.response = res;
event.source.postMessage(data, event.origin);
}
/**
* Send an error response to a postMessage request
* @param {Event} event The original postMessage request event
* @param {string} msg Error message
* @param {Error} nestedError Nested error event (optional)
*/
sendError(event, msg, nestedError) {
console.error('Action:' + event.data.action + ' failed with message: ' + msg);
const data = JSON.parse(JSON.stringify(event.data));
data.response = {
error: {
message: msg,
},
};
if (nestedError) {
data.response.error._error = nestedError;
}
event.source.postMessage(data, event.origin);
}
}

85
src/MatrixPostMessageApi.js
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@ -1,85 +0,0 @@
/*
Copyright 2017 New Vector Ltd
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
import Promise from "bluebird";
// NOTE: PostMessageApi only handles message events with a data payload with a
// response field
export default class PostMessageApi {
constructor(targetWindow, timeoutMs) {
this._window = targetWindow || window.parent; // default to parent window
this._timeoutMs = timeoutMs || 5000; // default to 5s timer
this._counter = 0;
this._requestMap = {
// $ID: {resolve, reject}
};
}
start() {
addEventListener('message', this.getOnMessageCallback());
}
stop() {
removeEventListener('message', this.getOnMessageCallback());
}
// Somewhat convoluted so we can successfully capture the PostMessageApi 'this' instance.
getOnMessageCallback() {
if (this._onMsgCallback) {
return this._onMsgCallback;
}
const self = this;
this._onMsgCallback = function(ev) {
// THIS IS ALL UNSAFE EXECUTION.
// We do not verify who the sender of `ev` is!
const payload = ev.data;
// NOTE: Workaround for running in a mobile WebView where a
// postMessage immediately triggers this callback even though it is
// not the response.
if (payload.response === undefined) {
return;
}
const promise = self._requestMap[payload._id];
if (!promise) {
return;
}
delete self._requestMap[payload._id];
promise.resolve(payload);
};
return this._onMsgCallback;
}
exec(action, target) {
this._counter += 1;
target = target || "*";
action._id = Date.now() + "-" + Math.random().toString(36) + "-" + this._counter;
return new Promise((resolve, reject) => {
this._requestMap[action._id] = {resolve, reject};
this._window.postMessage(action, target);
if (this._timeoutMs > 0) {
setTimeout(() => {
if (!this._requestMap[action._id]) {
return;
}
console.error("postMessage request timed out. Sent object: " + JSON.stringify(action));
this._requestMap[action._id].reject(new Error("Timed out"));
}, this._timeoutMs);
}
});
}
}

86
src/ToWidgetPostMessageApi.js Normal file
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@ -0,0 +1,86 @@
/*
Copyright 2018 New Vector Ltd
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
import Promise from "bluebird";
// const OUTBOUND_API_NAME = 'toWidget';
// Initiate requests using the "toWidget" postMessage API and handle responses
// NOTE: ToWidgetPostMessageApi only handles message events with a data payload with a
// response field
export default class ToWidgetPostMessageApi {
constructor(timeoutMs) {
this._timeoutMs = timeoutMs || 5000; // default to 5s timer
this._counter = 0;
this._requestMap = {
// $ID: {resolve, reject}
};
this.start = this.start.bind(this);
this.stop = this.stop.bind(this);
this.onPostMessage = this.onPostMessage.bind(this);
}
start() {
window.addEventListener('message', this.onPostMessage);
}
stop() {
window.removeEventListener('message', this.onPostMessage);
}
onPostMessage(ev) {
// THIS IS ALL UNSAFE EXECUTION.
// We do not verify who the sender of `ev` is!
const payload = ev.data;
// NOTE: Workaround for running in a mobile WebView where a
// postMessage immediately triggers this callback even though it is
// not the response.
if (payload.response === undefined) {
return;
}
const promise = this._requestMap[payload._id];
if (!promise) {
return;
}
delete this._requestMap[payload._id];
promise.resolve(payload);
}
// Initiate outbound requests (toWidget)
exec(action, targetWindow, targetOrigin) {
targetWindow = targetWindow || window.parent; // default to parent window
targetOrigin = targetOrigin || "*";
this._counter += 1;
action._id = Date.now() + "-" + Math.random().toString(36) + "-" + this._counter;
return new Promise((resolve, reject) => {
this._requestMap[action._id] = {resolve, reject};
targetWindow.postMessage(action, targetOrigin);
if (this._timeoutMs > 0) {
setTimeout(() => {
if (!this._requestMap[action._id]) {
return;
}
console.error("postMessage request timed out. Sent object: " + JSON.stringify(action),
this._requestMap);
this._requestMap[action._id].reject(new Error("Timed out"));
delete this._requestMap[action._id];
}, this._timeoutMs);
}
});
}
}

278
src/WidgetMessaging.js
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@ -19,38 +19,33 @@ limitations under the License.
* spec. details / documentation.
*/
import URL from 'url';
import dis from './dispatcher';
import MatrixPostMessageApi from './MatrixPostMessageApi';
import IntegrationManager from './IntegrationManager';
import FromWidgetPostMessageApi from './FromWidgetPostMessageApi';
import ToWidgetPostMessageApi from './ToWidgetPostMessageApi';
if (!global.mxFromWidgetMessaging) {
global.mxFromWidgetMessaging = new FromWidgetPostMessageApi();
global.mxFromWidgetMessaging.start();
}
if (!global.mxToWidgetMessaging) {
global.mxToWidgetMessaging = new ToWidgetPostMessageApi();
global.mxToWidgetMessaging.start();
}
const WIDGET_API_VERSION = '0.0.1'; // Current API version
const SUPPORTED_WIDGET_API_VERSIONS = [
'0.0.1',
];
const INBOUND_API_NAME = 'fromWidget';
const OUTBOUND_API_NAME = 'toWidget';
if (!global.mxWidgetMessagingListenerCount) {
global.mxWidgetMessagingListenerCount = 0;
}
if (!global.mxWidgetMessagingMessageEndpoints) {
global.mxWidgetMessagingMessageEndpoints = [];
}
export default class WidgetMessaging extends MatrixPostMessageApi {
constructor(widgetId, targetWindow) {
super(targetWindow);
export default class WidgetMessaging {
constructor(widgetId, widgetUrl, target) {
this.widgetId = widgetId;
this.startListening = this.startListening.bind(this);
this.stopListening = this.stopListening.bind(this);
this.onMessage = this.onMessage.bind(this);
this.widgetUrl = widgetUrl;
this.target = target;
this.fromWidget = global.mxFromWidgetMessaging;
this.toWidget = global.mxToWidgetMessaging;
this.start();
}
exec(action) {
return super.exec(action).then((data) => {
// check for errors and reject if found
messageToWidget(action) {
return this.toWidget.exec(action, this.target).then((data) => {
// Check for errors and reject if found
if (data.response === undefined) { // null is valid
throw new Error("Missing 'response' field");
}
@ -65,208 +60,23 @@ export default class WidgetMessaging extends MatrixPostMessageApi {
// We can't aggressively sanitize [A-z0-9] since it might be a translation.
throw new Error(msg);
}
// return the response field for the request
// Return the response field for the request
return data.response;
});
}
/**
* Register widget message event listeners
*/
startListening() {
if (global.mxWidgetMessagingListenerCount === 0) {
// Start postMessage API listener
this.start();
// Start widget specific listener
window.addEventListener("message", this.onMessage, false);
}
global.mxWidgetMessagingListenerCount += 1;
}
/**
* De-register widget message event listeners
*/
stopListening() {
global.mxWidgetMessagingListenerCount -= 1;
if (global.mxWidgetMessagingListenerCount === 0) {
// Stop widget specific listener
window.removeEventListener("message", this.onMessage, false);
// Stop postMessage API listener
this.stop();
}
if (global.mxWidgetMessagingListenerCount < 0) {
// Make an error so we get a stack trace
const e = new Error(
"WidgetMessaging: mismatched startListening / stopListening detected." +
" Negative count",
);
console.error(e);
}
}
/**
* Register a widget endpoint for trusted postMessage communication
* @param {string} widgetId Unique widget identifier
* @param {string} endpointUrl Widget wurl origin (protocol + (optional port) + host)
*/
addEndpoint(widgetId, endpointUrl) {
const u = URL.parse(endpointUrl);
if (!u || !u.protocol || !u.host) {
console.warn("Invalid origin:", endpointUrl);
return;
}
const origin = u.protocol + '//' + u.host;
const endpoint = new WidgetMessageEndpoint(widgetId, origin);
if (global.mxWidgetMessagingMessageEndpoints) {
if (global.mxWidgetMessagingMessageEndpoints.some(function(ep) {
return (ep.widgetId === widgetId && ep.endpointUrl === endpointUrl);
})) {
// Message endpoint already registered
console.warn("Endpoint already registered");
return;
} else {
// console.warn(`Adding widget messaging endpoint for ${widgetId}`);
global.mxWidgetMessagingMessageEndpoints.push(endpoint);
}
}
}
/**
* De-register a widget endpoint from trusted communication sources
* @param {string} widgetId Unique widget identifier
* @param {string} endpointUrl Widget wurl origin (protocol + (optional port) + host)
* @return {boolean} True if endpoint was successfully removed
*/
removeEndpoint(widgetId, endpointUrl) {
const u = URL.parse(endpointUrl);
if (!u || !u.protocol || !u.host) {
console.warn("Invalid origin");
return;
}
const origin = u.protocol + '//' + u.host;
if (global.mxWidgetMessagingMessageEndpoints && global.mxWidgetMessagingMessageEndpoints.length > 0) {
const length = global.mxWidgetMessagingMessageEndpoints.length;
global.mxWidgetMessagingMessageEndpoints = global.mxWidgetMessagingMessageEndpoints.
filter(function(endpoint) {
return (endpoint.widgetId != widgetId || endpoint.endpointUrl != origin);
});
return (length > global.mxWidgetMessagingMessageEndpoints.length);
}
return false;
}
/**
* Handle widget postMessage events
* @param {Event} event Event to handle
* @return {undefined}
*/
onMessage(event) {
if (!event.origin) { // Handle chrome
event.origin = event.originalEvent.origin;
}
// Event origin is empty string if undefined
if (
event.origin.length === 0 ||
!this.trustedEndpoint(event.origin) ||
event.data.api !== INBOUND_API_NAME ||
!event.data.widgetId
) {
return; // don't log this - debugging APIs like to spam postMessage which floods the log otherwise
}
const action = event.data.action;
const widgetId = event.data.widgetId;
if (action === 'content_loaded') {
dis.dispatch({
action: 'widget_content_loaded',
widgetId: widgetId,
});
this.sendResponse(event, {success: true});
} else if (action === 'supported_api_versions') {
this.sendResponse(event, {
api: INBOUND_API_NAME,
supported_versions: SUPPORTED_WIDGET_API_VERSIONS,
});
} else if (action === 'api_version') {
this.sendResponse(event, {
api: INBOUND_API_NAME,
version: WIDGET_API_VERSION,
});
} else if (action === 'm.sticker') {
dis.dispatch({action: 'm.sticker', data: event.data.widgetData, widgetId: event.data.widgetId});
} else if (action === 'integration_manager_open') {
// Close the stickerpicker
dis.dispatch({action: 'stickerpicker_close'});
// Open the integration manager
const data = event.data.widgetData;
const integType = (data && data.integType) ? data.integType : null;
const integId = (data && data.integId) ? data.integId : null;
IntegrationManager.open(integType, integId);
} else {
console.warn("Widget postMessage event unhandled");
this.sendError(event, {message: "The postMessage was unhandled"});
}
}
/**
* Check if message origin is registered as trusted
* @param {string} origin PostMessage origin to check
* @return {boolean} True if trusted
*/
trustedEndpoint(origin) {
if (!origin) {
return false;
}
return global.mxWidgetMessagingMessageEndpoints.some((endpoint) => {
return endpoint.endpointUrl === origin;
});
}
/**
* Send a postmessage response to a postMessage request
* @param {Event} event The original postMessage request event
* @param {Object} res Response data
*/
sendResponse(event, res) {
const data = JSON.parse(JSON.stringify(event.data));
data.response = res;
event.source.postMessage(data, event.origin);
}
/**
* Send an error response to a postMessage request
* @param {Event} event The original postMessage request event
* @param {string} msg Error message
* @param {Error} nestedError Nested error event (optional)
*/
sendError(event, msg, nestedError) {
console.error("Action:" + event.data.action + " failed with message: " + msg);
const data = JSON.parse(JSON.stringify(event.data));
data.response = {
error: {
message: msg,
},
};
if (nestedError) {
data.response.error._error = nestedError;
}
event.source.postMessage(data, event.origin);
}
/**
* Request a screenshot from a widget
* @return {Promise} To be resolved with screenshot data when it has been generated
*/
getScreenshot() {
return this.exec({
console.warn('Requesting screenshot for', this.widgetId);
return this.messageToWidget({
api: OUTBOUND_API_NAME,
action: "screenshot",
}).then((response) => response.screenshot)
.catch((error) => new Error("Failed to get screenshot: " + error.message));
})
.catch((error) => new Error("Failed to get screenshot: " + error.message))
.then((response) => response.screenshot);
}
/**
@ -274,30 +84,22 @@ export default class WidgetMessaging extends MatrixPostMessageApi {
* @return {Promise} To be resolved with an array of requested widget capabilities
*/
getCapabilities() {
return this.exec({
console.warn('Requesting capabilities for', this.widgetId);
return this.messageToWidget({
api: OUTBOUND_API_NAME,
action: "capabilities",
}).then((response) => response.capabilities);
}).then((response) => {
console.warn('Got capabilities for', this.widgetId, response.capabilities);
return response.capabilities;
});
}
}
/**
* Represents mapping of widget instance to URLs for trusted postMessage communication.
*/
class WidgetMessageEndpoint {
/**
* Mapping of widget instance to URL for trusted postMessage communication.
* @param {string} widgetId Unique widget identifier
* @param {string} endpointUrl Widget wurl origin.
*/
constructor(widgetId, endpointUrl) {
if (!widgetId) {
throw new Error("No widgetId specified in widgetMessageEndpoint constructor");
}
if (!endpointUrl) {
throw new Error("No endpoint specified in widgetMessageEndpoint constructor");
}
this.widgetId = widgetId;
this.endpointUrl = endpointUrl;
start() {
this.fromWidget.addEndpoint(this.widgetId, this.widgetUrl);
}
stop() {
this.fromWidget.removeEndpoint(this.widgetId, this.widgetUrl);
}
}

37
src/WidgetMessagingEndpoint.js Normal file
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@ -0,0 +1,37 @@
/*
Copyright 2018 New Vector Ltd
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
/**
* Represents mapping of widget instance to URLs for trusted postMessage communication.
*/
export default class WidgetMessageEndpoint {
/**
* Mapping of widget instance to URL for trusted postMessage communication.
* @param {string} widgetId Unique widget identifier
* @param {string} endpointUrl Widget wurl origin.
*/
constructor(widgetId, endpointUrl) {
if (!widgetId) {
throw new Error("No widgetId specified in widgetMessageEndpoint constructor");
}
if (!endpointUrl) {
throw new Error("No endpoint specified in widgetMessageEndpoint constructor");
}
this.widgetId = widgetId;
this.endpointUrl = endpointUrl;
}
}

35
src/components/views/elements/AppTile.js
View file

@ -51,6 +51,7 @@ export default class AppTile extends React.Component {
this._onSnapshotClick = this._onSnapshotClick.bind(this);
this.onClickMenuBar = this.onClickMenuBar.bind(this);
this._onMinimiseClick = this._onMinimiseClick.bind(this);
this._onInitialLoad = this._onInitialLoad.bind(this);
}
/**
@ -172,8 +173,7 @@ export default class AppTile extends React.Component {
// Widget postMessage listeners
try {
if (this.widgetMessaging) {
this.widgetMessaging.stopListening();
this.widgetMessaging.removeEndpoint(this.props.id, this.props.url);
this.widgetMessaging.stop();
}
} catch (e) {
console.error('Failed to stop listening for widgetMessaging events', e.message);
@ -290,14 +290,16 @@ export default class AppTile extends React.Component {
_onSnapshotClick(e) {
console.warn("Requesting widget snapshot");
this.widgetMessaging.getScreenshot().then((screenshot) => {
dis.dispatch({
action: 'picture_snapshot',
file: screenshot,
}, true);
}).catch((err) => {
console.error("Failed to get screenshot", err);
});
this.widgetMessaging.getScreenshot()
.catch((err) => {
console.error("Failed to get screenshot", err);
})
.then((screenshot) => {
dis.dispatch({
action: 'picture_snapshot',
file: screenshot,
}, true);
});
}
/* If user has permission to modify widgets, delete the widget,
@ -343,9 +345,16 @@ export default class AppTile extends React.Component {
* Called when widget iframe has finished loading
*/
_onLoaded() {
this.widgetMessaging = new WidgetMessaging(this.props.id, this.refs.appFrame.contentWindow);
this.widgetMessaging.startListening();
this.widgetMessaging.addEndpoint(this.props.id, this.props.url);
if (!this.widgetMessaging) {
this._onInitialLoad();
}
}
/**
* Called on initial load of the widget iframe
*/
_onInitialLoad() {
this.widgetMessaging = new WidgetMessaging(this.props.id, this.props.url, this.refs.appFrame.contentWindow);
this.widgetMessaging.getCapabilities().then((requestedCapabilities) => {
console.log(`Widget ${this.props.id} requested capabilities:`, requestedCapabilities);
requestedCapabilities = requestedCapabilities || [];