Java tutorial
/* * (C) Copyright 2014 Kurento (http://kurento.org/) * * 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. * */ package dk.apaq.orderly; import com.fasterxml.jackson.databind.ObjectMapper; import java.io.IOException; import java.util.concurrent.ConcurrentHashMap; import org.kurento.client.EventListener; import org.kurento.client.KurentoClient; import org.kurento.client.MediaPipeline; import org.kurento.client.OnIceCandidateEvent; import org.kurento.client.WebRtcEndpoint; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.socket.CloseStatus; import org.springframework.web.socket.TextMessage; import org.springframework.web.socket.WebSocketSession; import org.springframework.web.socket.handler.TextWebSocketHandler; import com.google.gson.Gson; import com.google.gson.GsonBuilder; import dk.apaq.orderly.common.security.TokenParser; import dk.apaq.orderly.model.BroadcastMessage; import dk.apaq.orderly.model.BroadcastMessageResponse; import dk.apaq.orderly.model.BroadcastMessageResponseType; import dk.apaq.orderly.model.BroadcastMessageType; import dk.apaq.orderly.model.IceCandidate; import dk.apaq.orderly.service.BroadcastService; import org.springframework.security.core.Authentication; import org.springframework.security.core.context.SecurityContextHolder; /** * Protocol handler for 1 to N video call communication. * * @author Boni Garcia (bgarcia@gsyc.es) * @since 5.0.0 */ public class CallHandler extends TextWebSocketHandler { private static final Logger log = LoggerFactory.getLogger(CallHandler.class); private static final Gson gson = new GsonBuilder().create(); private final ConcurrentHashMap<String, UserSession> viewers = new ConcurrentHashMap<>(); @Autowired private KurentoClient kurento; @Autowired BroadcastService broadcastService; @Autowired private ObjectMapper objectMapper; private MediaPipeline pipeline; private UserSession presenterUserSession; private BroadcastMessage resolveMessage(TextMessage message) throws Exception { BroadcastMessage bmsg = null; try { bmsg = objectMapper.readValue(message.getPayload(), BroadcastMessage.class); } catch (Exception ex) { log.error("Cannot resolve message.", ex); throw ex; } return bmsg; } @Override public void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception { BroadcastMessage bmsg = resolveMessage(message); //JsonObject jsonMessage = gson.fromJson(message.getPayload(), JsonObject.class); log.debug("Incoming message from session '{}': {}", session.getId(), bmsg); switch (bmsg.getId()) { case Presenter: try { presenter(session, bmsg); } catch (Throwable t) { handleErrorResponse(t, session, BroadcastMessageType.PresenterResponse); } break; case Viewer: try { viewer(session, bmsg); } catch (Throwable t) { handleErrorResponse(t, session, BroadcastMessageType.ViewerResponse); } break; case OnIceCandidate: { IceCandidate candidate = bmsg.getCandidate(); UserSession user = null; if (presenterUserSession != null) { if (presenterUserSession.getSession() == session) { user = presenterUserSession; } else { user = viewers.get(session.getId()); } } if (user != null) { user.addCandidate(candidate.toOrg()); } break; } case Stop: stop(session); break; default: break; } } private void handleErrorResponse(Throwable throwable, WebSocketSession session, BroadcastMessageType responseId) throws IOException { stop(session); log.error(throwable.getMessage(), throwable); BroadcastMessageResponse response = new BroadcastMessageResponse(responseId, BroadcastMessageResponseType.Rejected, throwable.getMessage()); session.sendMessage(new TextMessage(objectMapper.writeValueAsString(response))); } private synchronized void presenter(final WebSocketSession session, BroadcastMessage message) throws IOException { Authentication auth = (Authentication) session.getPrincipal(); auth = SecurityContextHolder.getContext().getAuthentication(); if (presenterUserSession == null) { presenterUserSession = new UserSession(session, objectMapper); pipeline = kurento.createMediaPipeline(); presenterUserSession.setWebRtcEndpoint(new WebRtcEndpoint.Builder(pipeline).build()); WebRtcEndpoint presenterWebRtc = presenterUserSession.getWebRtcEndpoint(); presenterWebRtc.addOnIceCandidateListener(new EventListener<OnIceCandidateEvent>() { @Override public void onEvent(OnIceCandidateEvent event) { BroadcastMessageResponse response = new BroadcastMessageResponse( BroadcastMessageType.IceCandidate, dk.apaq.orderly.model.IceCandidate.fromOrg(event.getCandidate())); try { synchronized (session) { session.sendMessage(new TextMessage(objectMapper.writeValueAsString(response))); } } catch (IOException e) { log.debug(e.getMessage()); } } }); String sdpOffer = message.getSdpOffer(); String sdpAnswer = presenterWebRtc.processOffer(sdpOffer); BroadcastMessageResponse response = new BroadcastMessageResponse(BroadcastMessageType.PresenterResponse, BroadcastMessageResponseType.Accepted); response.setSdpAnswer(sdpAnswer); synchronized (session) { presenterUserSession.sendMessage(response); } presenterWebRtc.gatherCandidates(); } else { BroadcastMessageResponse response = new BroadcastMessageResponse(BroadcastMessageType.PresenterResponse, BroadcastMessageResponseType.Rejected, "Another user is currently acting as sender. Try again later ..."); session.sendMessage(new TextMessage(objectMapper.writeValueAsString(response))); } } private synchronized void viewer(final WebSocketSession session, BroadcastMessage message) throws IOException { if (presenterUserSession == null || presenterUserSession.getWebRtcEndpoint() == null) { BroadcastMessageResponse response = new BroadcastMessageResponse(BroadcastMessageType.ViewerResponse, BroadcastMessageResponseType.Rejected, "No active sender now. Become sender or . Try again later ..."); session.sendMessage(new TextMessage(objectMapper.writeValueAsString(response))); } else { if (viewers.containsKey(session.getId())) { BroadcastMessageResponse response = new BroadcastMessageResponse( BroadcastMessageType.ViewerResponse, BroadcastMessageResponseType.Rejected, "You are already viewing in this session."); session.sendMessage(new TextMessage(objectMapper.writeValueAsString(response))); return; } UserSession viewer = new UserSession(session, objectMapper); viewers.put(session.getId(), viewer); WebRtcEndpoint nextWebRtc = new WebRtcEndpoint.Builder(pipeline).build(); nextWebRtc.addOnIceCandidateListener(new EventListener<OnIceCandidateEvent>() { @Override public void onEvent(OnIceCandidateEvent event) { BroadcastMessageResponse response = new BroadcastMessageResponse( BroadcastMessageType.IceCandidate, dk.apaq.orderly.model.IceCandidate.fromOrg(event.getCandidate())); try { synchronized (session) { session.sendMessage(new TextMessage(objectMapper.writeValueAsString(response))); } } catch (IOException e) { log.debug(e.getMessage()); } } }); viewer.setWebRtcEndpoint(nextWebRtc); presenterUserSession.getWebRtcEndpoint().connect(nextWebRtc); String sdpOffer = message.getSdpOffer(); String sdpAnswer = nextWebRtc.processOffer(sdpOffer); BroadcastMessageResponse response = new BroadcastMessageResponse(BroadcastMessageType.ViewerResponse, BroadcastMessageResponseType.Accepted); response.setSdpAnswer(sdpAnswer); synchronized (session) { viewer.sendMessage(response); } nextWebRtc.gatherCandidates(); } } private synchronized void stop(WebSocketSession session) throws IOException { String sessionId = session.getId(); if (presenterUserSession != null && presenterUserSession.getSession().getId().equals(sessionId)) { for (UserSession viewer : viewers.values()) { viewer.sendMessage(new BroadcastMessageResponse(BroadcastMessageType.StopCommunication)); } log.info("Releasing media pipeline"); if (pipeline != null) { pipeline.release(); } pipeline = null; presenterUserSession = null; } else if (viewers.containsKey(sessionId)) { if (viewers.get(sessionId).getWebRtcEndpoint() != null) { viewers.get(sessionId).getWebRtcEndpoint().release(); } viewers.remove(sessionId); } } @Override public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception { stop(session); } }