Overview
Since build 5.2.935 in is possible to send an event from publishing client which is biund to the stream published, and to pass the event to all the stream subscribers. Today, the feature is used to notify subscribers when publisher mutes/unmutes audio/video.
Sending stream event from publiher
To send a stream event, the function Stream.sendStreamEvent() is called on client side with event type parameter. For example, stream audio state events are sending when Stream.muteAudio() and Stream.unmuteAudio() are called as follows:
var muteAudio = function muteAudio() {
if (mediaConnection) {
mediaConnection.muteAudio();
sendStreamEvent(STREAM_EVENT_TYPE.AUDIO_MUTED);
}
};
...
var unmuteAudio = function unmuteAudio() {
if (mediaConnection) {
mediaConnection.unmuteAudio();
sendStreamEvent(STREAM_EVENT_TYPE.AUDIO_UNMUTED);
}
};
Stream video state events are sending when Stream.muteVideo() and Stream.unmuteVideo() are called:
var muteVideo = function muteVideo() {
if (mediaConnection) {
mediaConnection.muteVideo();
sendStreamEvent(STREAM_EVENT_TYPE.VIDEO_MUTED);
}
};
...
var unmuteVideo = function unmuteVideo() {
if (mediaConnection) {
mediaConnection.unmuteVideo();
sendStreamEvent(STREAM_EVENT_TYPE.VIDEO_UNMUTED);
}
};
Receiving stream event on subscribers side
When stream event is passed, all the subscribers receive the STREAM_EVENT event
previewStream = session.createStream({
name: streamName,
display: remoteVideo,
...
}).on(STREAM_EVENT, function(streamEvent) {
switch (streamEvent.type) {
case STREAM_EVENT_TYPE.AUDIO_MUTED:
$("#audioMuted").text(true);
break;
case STREAM_EVENT_TYPE.AUDIO_UNMUTED:
$("#audioMuted").text(false);
break;
case STREAM_EVENT_TYPE.VIDEO_MUTED:
$("#videoMuted").text(true);
break;
case STREAM_EVENT_TYPE.VIDEO_UNMUTED:
$("#videoMuted").text(false);
break;
}
console.log("Received streamEvent ", streamEvent.type);
});
Stream event processing on backend
To process stream events on backend server, sendStreamEvent and StreamEvent methods should be added to the application
add app-rest-method MyAppKey sendStreamEvent add app-rest-method MyAppKey StreamEvent
Then backend server will receive sendStreamEvent
URL:http://localhost:8081/apps/EchoApp/sendStreamEvent
OBJECT:
{
"nodeId" : "qg4BeHzYSAtkhUkXgnSMEUZpsshaLPL5@192.168.0.39",
"appKey" : "defaultApp",
"sessionId" : "/192.168.0.83:64573/192.168.0.39:8443-a98bb891-aeaf-46a8-8fba-772e07ac035b",
"mediaSessionId" : "9906b2b0-9c28-11eb-8d20-75f877676678",
"type" : "audioMuted",
"info" : "",
"origin" : "https://wcs:8888"
}
if publisher mutes the stream.
Also, backend will receive StreamEvent per every the stream subscriber
URL:http://localhost:8081/apps/EchoApp/StreamEvent
OBJECT:
{
"nodeId" : "qg4BeHzYSAtkhUkXgnSMEUZpsshaLPL5@192.168.0.39",
"appKey" : "defaultApp",
"sessionId" : "/192.168.0.83:64573/192.168.0.39:8443-a98bb891-aeaf-46a8-8fba-772e07ac035b",
"mediaSessionId" : "9fed5c50-9c28-11eb-8d20-75f877676678",
"type" : "audioMuted",
"info" : ""
}