/*
* (C) Copyright 2013 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 org.kurento.jsonrpc.internal.server;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.METHOD_CLOSE;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.METHOD_CONNECT;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.METHOD_PING;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.PONG;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.PONG_PAYLOAD;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.RECONNECTION_ERROR;
import static org.kurento.jsonrpc.internal.JsonRpcConstants.RECONNECTION_SUCCESSFUL;
import java.io.IOException;
import java.lang.reflect.Type;
import java.text.SimpleDateFormat;
import java.util.Collections;
import java.util.Date;
import java.util.List;
import java.util.concurrent.ScheduledFuture;
import javax.annotation.PostConstruct;
import org.kurento.commons.SecretGenerator;
import org.kurento.jsonrpc.JsonRpcHandler;
import org.kurento.jsonrpc.JsonUtils;
import org.kurento.jsonrpc.internal.JsonRpcHandlerManager;
import org.kurento.jsonrpc.internal.client.AbstractSession;
import org.kurento.jsonrpc.internal.client.TransactionImpl.ResponseSender;
import org.kurento.jsonrpc.internal.server.PingWatchdogManager.NativeSessionCloser;
import org.kurento.jsonrpc.message.Request;
import org.kurento.jsonrpc.message.Response;
import org.kurento.jsonrpc.message.ResponseError;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.core.task.TaskRejectedException;
import org.springframework.scheduling.TaskScheduler;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonPrimitive;
import com.google.gson.reflect.TypeToken;
public class ProtocolManager {
public static final String CLIENT_CLOSED_CLOSE_REASON = "Client sent close message";
private static final String INTERVAL_PROPERTY = "interval";
public interface ServerSessionFactory {
ServerSession createSession(String sessionId, Object registerInfo,
SessionsManager sessionsManager);
void updateSessionOnReconnection(ServerSession session);
}
private static final Logger log = LoggerFactory.getLogger(ProtocolManager.class);
private static final SimpleDateFormat format = new SimpleDateFormat("MM-dd-yyyy hh:mm:ss,S");
protected SecretGenerator secretGenerator = new SecretGenerator();
@Autowired
private SessionsManager sessionsManager;
@Autowired
@Qualifier("jsonrpcTaskScheduler")
private TaskScheduler taskScheduler;
private final JsonRpcHandlerManager handlerManager;
private String label = "";
private int maxHeartbeats = 0;
private int heartbeats = 0;
private PingWatchdogManager pingWachdogManager;
public ProtocolManager(JsonRpcHandler<?> handler) {
this.handlerManager = new JsonRpcHandlerManager(handler);
}
public ProtocolManager(JsonRpcHandler<?> handler, SessionsManager sessionsManager,
TaskScheduler taskScheduler) {
this.handlerManager = new JsonRpcHandlerManager(handler);
this.sessionsManager = sessionsManager;
this.taskScheduler = taskScheduler;
postConstruct();
}
@PostConstruct
private void postConstruct() {
NativeSessionCloser nativeSessionCloser = new NativeSessionCloser() {
@Override
public void closeSession(String transportId) {
ServerSession serverSession = sessionsManager.getByTransportId(transportId);
if (serverSession != null) {
serverSession.closeNativeSession("Close for not receive ping from client");
} else {
log.warn("Ping wachdog trying to close a non-registered ServerSession");
}
}
};
this.pingWachdogManager = new PingWatchdogManager(taskScheduler, nativeSessionCloser);
}
public void setLabel(String label) {
this.label = "[" + label + "] ";
}
public void processMessage(String messageJson, ServerSessionFactory factory,
ResponseSender responseSender, String internalSessionId) throws IOException {
JsonObject messagetJsonObject = JsonUtils.fromJson(messageJson, JsonObject.class);
processMessage(messagetJsonObject, factory, responseSender, internalSessionId);
}
/**
* Process incoming message. The response is sent using responseSender. If null, the session will
* be used.
*
* @param messagetJsonObject
* @param factory
* @param responseSender
* @param internalSessionId
* @throws IOException
*/
public void processMessage(JsonObject messagetJsonObject, ServerSessionFactory factory,
ResponseSender responseSender, String internalSessionId) throws IOException {
if (messagetJsonObject.has(Request.METHOD_FIELD_NAME)) {
processRequestMessage(factory, messagetJsonObject, responseSender, internalSessionId);
} else {
processResponseMessage(messagetJsonObject, internalSessionId);
}
}
// TODO Unify ServerSessionFactory, ResponseSender and transportId in a
// entity "RequestContext" or similar. In this way, there are less
// parameters
// and the implementation is easier
private void processRequestMessage(ServerSessionFactory factory, JsonObject requestJsonObject,
final ResponseSender responseSender, String transportId) throws IOException {
final Request<JsonElement> request = JsonUtils.fromJsonRequest(requestJsonObject,
JsonElement.class);
switch (request.getMethod()) {
case METHOD_CONNECT:
log.debug("{} Req-> {} (transportId={})", label, request, transportId);
processReconnectMessage(factory, request, responseSender, transportId);
break;
case METHOD_PING:
log.trace("{} Req-> {} (transportId={})", label, request, transportId);
processPingMessage(factory, request, responseSender, transportId);
break;
case METHOD_CLOSE:
log.trace("{} Req-> {} (transportId={})", label, request, transportId);
processCloseMessage(factory, request, responseSender, transportId);
break;
default:
final ServerSession session = getOrCreateSession(factory, transportId, request);
log.debug("{} Req-> {} [jsonRpcSessionId={}, transportId={}]", label, request,
session.getSessionId(), transportId);
// TODO, Take out this an put in Http specific handler. The main
// reason is to wait for request before responding to the client.
// And for no contaminate the ProtocolManager.
if (request.getMethod().equals(Request.POLL_METHOD_NAME)) {
Type collectionType = new TypeToken<List<Response<JsonElement>>>() {
}.getType();
List<Response<JsonElement>> responseList = JsonUtils.fromJson(request.getParams(),
collectionType);
for (Response<JsonElement> response : responseList) {
session.handleResponse(response);
}
// Wait for some time if there is a request from server to
// client
// TODO Allow send empty responses. Now you have to send at
// least an
// empty string
responseSender.sendResponse(new Response<Object>(request.getId(), Collections.emptyList()));
} else {
session.processRequest(new Runnable() {
@Override
public void run() {
handlerManager.handleRequest(session, request, responseSender);
}
});
}
break;
}
}
private ServerSession getOrCreateSession(ServerSessionFactory factory, String transportId,
Request<JsonElement> request) {
ServerSession session = null;
String reqSessionId = request.getSessionId();
if (reqSessionId != null) {
session = sessionsManager.get(reqSessionId);
if (session == null) {
session = createSessionAsOldIfKnowByHandler(factory, reqSessionId);
if (session == null) {
log.warn(label + "There is no session with specified id '{}'." + "Creating a new one.",
reqSessionId);
}
}
} else if (transportId != null) {
session = sessionsManager.getByTransportId(transportId);
}
if (session == null) {
session = createSession(factory, null);
handlerManager.afterConnectionEstablished(session);
} else {
session.setNew(false);
}
return session;
}
private ServerSession createSessionAsOldIfKnowByHandler(ServerSessionFactory factory,
String reqSessionId) {
ServerSession session = null;
JsonRpcHandler<?> handler = handlerManager.getHandler();
if (handler instanceof NativeSessionHandler) {
NativeSessionHandler nativeHandler = (NativeSessionHandler) handler;
if (nativeHandler.isSessionKnown(reqSessionId)) {
log.debug("Session {} is already known by NativeSessionHandler", reqSessionId);
session = createSession(factory, null, reqSessionId);
session.setNew(false);
nativeHandler.processNewCreatedKnownSession(session);
}
}
return session;
}
private void processPingMessage(ServerSessionFactory factory, Request<JsonElement> request,
ResponseSender responseSender, String transportId) throws IOException {
if (maxHeartbeats == 0 || maxHeartbeats > ++heartbeats) {
long interval = -1;
if (request.getParams() != null) {
JsonObject element = (JsonObject) request.getParams();
if (element.has(INTERVAL_PROPERTY)) {
interval = element.get(INTERVAL_PROPERTY).getAsLong();
}
}
pingWachdogManager.pingReceived(transportId, interval);
String sessionId = request.getSessionId();
JsonObject pongPayload = new JsonObject();
pongPayload.add(PONG_PAYLOAD, new JsonPrimitive(PONG));
responseSender.sendPingResponse(new Response<>(sessionId, request.getId(), pongPayload));
}
}
private void processCloseMessage(ServerSessionFactory factory, Request<JsonElement> request,
ResponseSender responseSender, String transportId) {
ServerSession session = sessionsManager.getByTransportId(transportId);
if (session != null) {
session.setGracefullyClosed();
cancelCloseTimer(session);
}
try {
responseSender.sendResponse(new Response<>(request.getId(), "bye"));
} catch (IOException e) {
log.warn("Exception sending close message response to client", e);
}
if (session != null) {
this.closeSession(session, CLIENT_CLOSED_CLOSE_REASON);
}
}
private void processReconnectMessage(ServerSessionFactory factory, Request<JsonElement> request,
ResponseSender responseSender, String transportId) throws IOException {
String sessionId = request.getSessionId();
if (sessionId == null) {
ServerSession session = getOrCreateSession(factory, transportId, request);
responseSender.sendResponse(new Response<>(session.getSessionId(), request.getId(), "OK"));
} else {
ServerSession session = sessionsManager.get(sessionId);
if (session != null) {
String oldTransportId = session.getTransportId();
session.setTransportId(transportId);
factory.updateSessionOnReconnection(session);
pingWachdogManager.updateTransportId(transportId, oldTransportId);
sessionsManager.updateTransportId(session, oldTransportId);
// FIXME: Possible race condition if session is disposed when
// reconnect method has arrived
cancelCloseTimer(session);
responseSender
.sendResponse(new Response<>(sessionId, request.getId(), RECONNECTION_SUCCESSFUL));
} else {
session = createSessionAsOldIfKnowByHandler(factory, sessionId);
if (session != null) {
responseSender
.sendResponse(new Response<>(sessionId, request.getId(), RECONNECTION_SUCCESSFUL));
} else {
responseSender.sendResponse(
new Response<>(request.getId(), new ResponseError(40007, RECONNECTION_ERROR)));
}
}
}
}
private ServerSession createSession(ServerSessionFactory factory, Object registerInfo,
String sessionId) {
ServerSession session = factory.createSession(sessionId, registerInfo, sessionsManager);
pingWachdogManager.associateSessionId(session.getTransportId(), sessionId);
sessionsManager.put(session);
return session;
}
private ServerSession createSession(ServerSessionFactory factory, Object registerInfo) {
String sessionId = secretGenerator.nextSecret();
return createSession(factory, registerInfo, sessionId);
}
private void processResponseMessage(JsonObject messagetJsonObject, String internalSessionId) {
Response<JsonElement> response = JsonUtils.fromJsonResponse(messagetJsonObject,
JsonElement.class);
ServerSession session = sessionsManager.getByTransportId(internalSessionId);
if (session != null) {
session.handleResponse(response);
} else {
log.debug("Processing response {} for non-existent session {}", response.toString(),
internalSessionId);
}
}
public void closeSessionIfTimeout(final String transportId, final String reason) {
final ServerSession session = sessionsManager.getByTransportId(transportId);
if (session != null) {
try {
Date closeTime = new Date(
System.currentTimeMillis() + session.getReconnectionTimeoutInMillis());
log.debug(label + "Configuring close timeout for session: {} transportId: {} at {}",
session.getSessionId(), transportId, format.format(closeTime));
ScheduledFuture<?> lastStartedTimerFuture = taskScheduler.schedule(new Runnable() {
@Override
public void run() {
closeSession(session, reason);
}
}, closeTime);
session.setCloseTimerTask(lastStartedTimerFuture);
pingWachdogManager.disablePingWatchdogForSession(transportId);
} catch (TaskRejectedException e) {
log.warn(label + "Close timeout for session {} with transportId {} can not be set "
+ "because the scheduler is shutdown", session.getSessionId(), transportId);
}
}
}
public void closeSession(ServerSession session, String reason) {
log.debug("{} Removing session {} with transportId {} in ProtocolManager", label,
session.getSessionId(), session.getTransportId());
try {
session.close();
} catch (IOException e) {
log.warn("{} Could not close WsSession session {}", label, session.getSessionId(), e);
}
sessionsManager.remove(session);
pingWachdogManager.removeSession(session);
handlerManager.afterConnectionClosed(session, reason);
}
public void cancelCloseTimer(ServerSession session) {
if (session.getCloseTimerTask() != null) {
session.getCloseTimerTask().cancel(false);
}
}
public void processTransportError(String transportId, Throwable exception) {
final ServerSession session = sessionsManager.getByTransportId(transportId);
handlerManager.handleTransportError(session, exception);
}
/**
* Method intended to be used for testing purposes
*
* @param maxHeartbeats
*/
public void setMaxNumberOfHeartbeats(int maxHeartbeats) {
this.maxHeartbeats = maxHeartbeats;
}
public void setPingWachdog(boolean pingWachdog) {
this.pingWachdogManager.setPingWatchdog(pingWachdog);
}
public AbstractSession getSessionByTransportId(String transportId) {
return sessionsManager.getByTransportId(transportId);
}
}