Add postmessage api and move functions in to class

This commit is contained in:
Richard Lewis 2017-12-15 15:24:22 +00:00
parent f410112983
commit c234e209fb
2 changed files with 286 additions and 163 deletions

View file

@ -112,14 +112,14 @@ Example:
*/
import URL from 'url';
import dis from './dispatcher';
import MatrixPostMessageApi from './MatrixPostMessageApi';
const WIDGET_API_VERSION = '0.0.1'; // Current API version
const SUPPORTED_WIDGET_API_VERSIONS = [
'0.0.1',
];
import dis from './dispatcher';
if (!global.mxWidgetMessagingListenerCount) {
global.mxWidgetMessagingListenerCount = 0;
}
@ -127,176 +127,205 @@ if (!global.mxWidgetMessagingMessageEndpoints) {
global.mxWidgetMessagingMessageEndpoints = [];
}
/**
* Register widget message event listeners
*/
function startListening() {
if (global.mxWidgetMessagingListenerCount === 0) {
window.addEventListener("message", onMessage, false);
}
global.mxWidgetMessagingListenerCount += 1;
}
/**
* De-register widget message event listeners
*/
function stopListening() {
global.mxWidgetMessagingListenerCount -= 1;
if (global.mxWidgetMessagingListenerCount === 0) {
window.removeEventListener("message", onMessage);
}
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)
*/
function addEndpoint(widgetId, endpointUrl) {
const u = URL.parse(endpointUrl);
if (!u || !u.protocol || !u.host) {
console.warn("Invalid origin:", endpointUrl);
return;
export default class WidgetMessaging extends MatrixPostMessageApi {
constructor(targetWindow) {
super(targetWindow);
}
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");
exec(action) {
return super.exec(action).then((data) => {
// check for errors and reject if found
if (data.response === undefined) { // null is valid
throw new Error("Missing 'response' field");
}
if (data.response && data.response.error) {
const err = data.response.error;
const msg = String(err.message ? err.message : "An error was returned");
if (err._error) {
console.error(err._error);
}
// Potential XSS attack if 'msg' is not appropriately sanitized,
// as it is untrusted input by our parent window (which we assume is Riot).
// 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 data.response;
});
}
/**
* Register widget message event listeners
*/
startListening() {
if (global.mxWidgetMessagingListenerCount === 0) {
window.addEventListener("message", this.onMessage, false);
}
global.mxWidgetMessagingListenerCount += 1;
}
/**
* De-register widget message event listeners
*/
stopListening() {
global.mxWidgetMessagingListenerCount -= 1;
if (global.mxWidgetMessagingListenerCount === 0) {
window.removeEventListener("message", this.onMessage);
}
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;
}
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
*/
function 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;
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;
}
global.mxWidgetMessagingMessageEndpoints.push(endpoint);
}
}
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;
}
/**
* 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;
}
/**
* Handle widget postMessage events
* @param {Event} event Event to handle
* @return {undefined}
*/
function onMessage(event) {
if (!event.origin) { // Handle chrome
event.origin = event.originalEvent.origin;
}
// Event origin is empty string if undefined
if (
event.origin.length === 0 ||
!trustedEndpoint(event.origin) ||
event.data.api !== "widget" ||
!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,
});
sendResponse(event, {success: true});
} else if (action === 'supported_api_versions') {
sendResponse(event, {
api: "widget",
supported_versions: SUPPORTED_WIDGET_API_VERSIONS,
});
} else if (action === 'api_version') {
sendResponse(event, {
api: "widget",
version: WIDGET_API_VERSION,
});
} else {
console.warn("Widget postMessage event unhandled");
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
*/
function trustedEndpoint(origin) {
if (!origin) {
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;
}
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
*/
function sendResponse(event, res) {
const data = JSON.parse(JSON.stringify(event.data));
data.response = res;
event.source.postMessage(data, event.origin);
}
/**
* Handle widget postMessage events
* @param {Event} event Event to handle
* @return {undefined}
*/
onMessage(event) {
if (!event.origin) { // Handle chrome
event.origin = event.originalEvent.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)
*/
function 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 origin is empty string if undefined
if (
event.origin.length === 0 ||
!this.trustedEndpoint(event.origin) ||
event.data.api !== "widget" ||
!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: "widget",
supported_versions: SUPPORTED_WIDGET_API_VERSIONS,
});
} else if (action === 'api_version') {
this.sendResponse(event, {
api: "widget",
version: WIDGET_API_VERSION,
});
} 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);
}
event.source.postMessage(data, event.origin);
}
/**
* Represents mapping of widget instance to URLs for trusted postMessage communication.
*/
@ -317,10 +346,3 @@ class WidgetMessageEndpoint {
this.endpointUrl = endpointUrl;
}
}
export default {
startListening: startListening,
stopListening: stopListening,
addEndpoint: addEndpoint,
removeEndpoint: removeEndpoint,
};