janus-java-client

This library provide a Java client to manage Janus gateway WebRTC. Working features:

• Start a live stream to Janus server
• Subscribe a live stream from Janus server
• Handle some events from Janus then forward to clients
• Support Video room plugin: create/join/leave/delete a video room. Other features of Video room plugin will be supported soon.

Everything is early state, feel free to contribute and request features!

Signaling server

Janus server and client need to exchange connection information, there is a working example in the /signaling folder (include frontend with jQuery, backend with Java support websocket and signaling process)

JanusClient

JanusClient take care about how to interactive with Janus server: create Janus session, attach to plugin, send message to Janus

• public JanusClient(MessageCallback messageCallback, String address): Constructor of class
  • messageCallback: There are some Janus's messages don't have transactionId then Janus client cannot find a handler to process. Those messages will forward to user's context
  • address: URL of Janus's websocket, if the URL doesn't start with "ws" nor "wss", a "ws://" will be appended at start of the URL
• public boolean connect(): Connect Janus client to Janus server,
  • return true if connect successful
• public Long createSession(): Create a Janus session, this function should be called after the method connect() is success
  • return a sessionId in Long
• public long attachToPlugin(Long sessionId, String pluginName, JSONObject data): Attach to any plugin of Janus server
  • sessionId: Janus session ID of user
  • pluginName: plugin will handle the command
  • data: data of command
  • return handleId of user in context of the plugin
• public void sendToSession(String transactionId, Long sessionId, JSONObject data, JanusTransactionAbstractHandler handler): Send a command/event to a plugin
  • transactionId: a random string that the client can use to match response messages from the Janus server.
  • sessionId: Janus session ID of user
  • data: information about the command
  • handler: object will process returned message
• public long destroySession(Long sessionId): Kill an exists Janus session
  • sessionId: Janus session ID of user

VideoRoomAdaptor

VideoRoomAdaptor provide APIs to work with Video Room plugin: create/join/leave/delete a video room. Most of methods require

• sessionId: Janus sessionId of user
• handleId: Unique Id of user in the context of plugin, created when user attach to plugin All APIs:
• public Long attachToVideoRoom(Long sessionId): Create a handleId for interacting with Videoroom plugin
  • sessionId: Janus session ID of user
  • return a handleId in Long for future interaction
• public long createRoom(Long sessionId, Long handleId):
  • return a unique room name that has just created
• public JSONObject getAllRooms(Long sessionId, Long handleId):
  • return A JSON represent all rooms with detail information
• public JSONObject publisherJoinRoom(Long sessionId, Long handleId, long roomName, String displayName): "publishers are those participant handles that are able (although may choose not to, more on this later) publish media in the room"
  • roomName: unique room name in long
  • displayName: a name for display in VideoRoom, can be duplicated
  • return Information about the room
• public String startLive(Long sessionId, Long handleId, String sdp)
  • spd: SDP offer describe connection info, to start handshake process
  • return SDP answer from Janus server
• public void sendConnectionInfo(Long sessionId, Long handleId, JSONObject candidate): Client send ICE candidates to Janus server. A RTCConnection can have multiple candidate, then call this method multiple times.
  • candidate: information about a candidate
• public void sendCompleteIceGathering(Long sessionId, Long handleId): Client notice that they send all candidates, signaling server will send a special event to tell Janus server.
• public JSONObject subscriberJoinRoom(Long sessionId, Long handleId, long roomName, String displayName, long[] feederIds, Long privateId): "subscribers are NOT participants, but simply handles that will be used exclusively to receive media from one or more publishers in the room"
  • roomName: Unique room name to join
  • displayName: A name to show to other participants in the room
  • feederIds: List of streams to subscribe, Janus support to subscribe multiple stream, but currently, the library support only one
  • return A SDP offer from Janus, clients have to process this message then return a SDP answer with the next method
• public String sendViewerSDPAnswer(Long sessionId, Long handleId, String sdp, Long roomId): After receive SDP offer from Janus, subscriber has to process and return a SDP answer
  • sdp: SDP answer
  • roomId: Unique room name to join
  • return output of subscriber join
• public JSONObject stopPublishStream(Long sessionId, Long handleId): stop publish a stream
  • return output of action
• public void leaveRoom(Long sessionId, Long handleId): a publisher/subscriber left room and stop publish/subscribe a stream
• public void destroyRoom(Long sessionId, Long roomId, Long handleId): delete a room
  • roomId: unique room name to destroy

Examples

public class TestMainFlow {
    @Test
    public void testVideoRoom() {
        VideoRoomAdaptor videoRoomAdaptor = new VideoRoomAdaptor(client);
        Long sessionId = client.createSession();
        Long handleId = videoRoomAdaptor.attachToVideoRoom(sessionId);
        System.out.printf(videoRoomAdaptor.getAllRooms(sessionId, handleId).toString());
        videoRoomAdaptor.publisherJoinRoom(sessionId, handleId, 1234, "janus-java-client");
        videoRoomAdaptor.leaveRoom(sessionId, handleId);
    }
}

Please refer to file TestMainFlow and folder /signaling for detail information