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/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const {
LongStringActor,
const {
TYPES: { SERVER_SENT_EVENT },
const eventSourceEventService = Cc[
"@mozilla.org/eventsourceevent/service;1"
].getService(Ci.nsIEventSourceEventService);
class ServerSentEventWatcher {
constructor() {
this.windowIds = new Set();
// Register for backend events.
this.onWindowReady = this.onWindowReady.bind(this);
this.onWindowDestroy = this.onWindowDestroy.bind(this);
}
/**
* Start watching for all server sent events related to a given Target Actor.
*
* @param TargetActor targetActor
* The target actor on which we should observe server sent events.
* @param Object options
* Dictionary object with following attributes:
* - onAvailable: mandatory function
* This will be called for each resource.
*/
watch(targetActor, { onAvailable }) {
this.onAvailable = onAvailable;
this.targetActor = targetActor;
for (const window of this.targetActor.windows) {
const { innerWindowId } = window.windowGlobalChild;
this.startListening(innerWindowId);
}
// Listen for subsequent top-level-document reloads/navigations,
// new iframe additions or current iframe reloads/navigation.
this.targetActor.on("window-ready", this.onWindowReady);
this.targetActor.on("window-destroyed", this.onWindowDestroy);
}
static createResource(messageType, eventParams) {
return {
resourceType: SERVER_SENT_EVENT,
messageType,
...eventParams,
};
}
static prepareFramePayload(targetActor, frame) {
const payload = new LongStringActor(targetActor.conn, frame);
targetActor.manage(payload);
return payload.form();
}
onWindowReady({ window }) {
const { innerWindowId } = window.windowGlobalChild;
this.startListening(innerWindowId);
}
onWindowDestroy({ id }) {
this.stopListening(id);
}
startListening(innerWindowId) {
if (!this.windowIds.has(innerWindowId)) {
this.windowIds.add(innerWindowId);
eventSourceEventService.addListener(innerWindowId, this);
}
}
stopListening(innerWindowId) {
if (this.windowIds.has(innerWindowId)) {
this.windowIds.delete(innerWindowId);
// The listener might have already been cleaned up on `window-destroy`.
if (!eventSourceEventService.hasListenerFor(innerWindowId)) {
console.warn(
"Already stopped listening to server sent events for this window."
);
return;
}
eventSourceEventService.removeListener(innerWindowId, this);
}
}
destroy() {
// cleanup any other listeners not removed on `window-destroy`
for (const id of this.windowIds) {
this.stopListening(id);
}
this.targetActor.off("window-ready", this.onWindowReady);
this.targetActor.off("window-destroyed", this.onWindowDestroy);
}
// nsIEventSourceEventService specific functions
eventSourceConnectionOpened() {}
eventSourceConnectionClosed(httpChannelId) {
const resource = ServerSentEventWatcher.createResource(
"eventSourceConnectionClosed",
{ httpChannelId }
);
this.onAvailable([resource]);
}
eventReceived(httpChannelId, eventName, lastEventId, data, retry, timeStamp) {
const payload = ServerSentEventWatcher.prepareFramePayload(
this.targetActor,
data
);
const resource = ServerSentEventWatcher.createResource("eventReceived", {
httpChannelId,
data: {
payload,
eventName,
lastEventId,
retry,
timeStamp,
},
});
this.onAvailable([resource]);
}
}
module.exports = ServerSentEventWatcher;