WsHttpUpgradeHandler.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.tomcat.websocket.server;
import java.io.EOFException;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpSession;
import javax.servlet.http.WebConnection;
import javax.websocket.CloseReason;
import javax.websocket.CloseReason.CloseCodes;
import javax.websocket.DeploymentException;
import javax.websocket.Endpoint;
import javax.websocket.Extension;
import javax.websocket.server.ServerEndpointConfig;
import org.apache.coyote.http11.upgrade.InternalHttpUpgradeHandler;
import org.apache.coyote.http11.upgrade.UpgradeInfo;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.net.AbstractEndpoint.Handler.SocketState;
import org.apache.tomcat.util.net.SSLSupport;
import org.apache.tomcat.util.net.SocketEvent;
import org.apache.tomcat.util.net.SocketWrapperBase;
import org.apache.tomcat.util.res.StringManager;
import org.apache.tomcat.websocket.Transformation;
import org.apache.tomcat.websocket.WsIOException;
import org.apache.tomcat.websocket.WsSession;
/**
* Servlet 3.1 HTTP upgrade handler for WebSocket connections.
*/
public class WsHttpUpgradeHandler implements InternalHttpUpgradeHandler {
private final Log log = LogFactory.getLog(WsHttpUpgradeHandler.class); // must not be static
private static final StringManager sm = StringManager.getManager(WsHttpUpgradeHandler.class);
private final ClassLoader applicationClassLoader;
private SocketWrapperBase<?> socketWrapper;
private UpgradeInfo upgradeInfo = new UpgradeInfo();
private Endpoint ep;
private ServerEndpointConfig serverEndpointConfig;
private WsServerContainer webSocketContainer;
private WsHandshakeRequest handshakeRequest;
private List<Extension> negotiatedExtensions;
private String subProtocol;
private Transformation transformation;
private Map<String, String> pathParameters;
private boolean secure;
private WebConnection connection;
private WsRemoteEndpointImplServer wsRemoteEndpointServer;
private WsFrameServer wsFrame;
private WsSession wsSession;
public WsHttpUpgradeHandler() {
applicationClassLoader = Thread.currentThread().getContextClassLoader();
}
@Override
public void setSocketWrapper(SocketWrapperBase<?> socketWrapper) {
this.socketWrapper = socketWrapper;
}
public void preInit(ServerEndpointConfig serverEndpointConfig, WsServerContainer wsc,
WsHandshakeRequest handshakeRequest, List<Extension> negotiatedExtensionsPhase2, String subProtocol,
Transformation transformation, Map<String, String> pathParameters, boolean secure) {
this.serverEndpointConfig = serverEndpointConfig;
this.webSocketContainer = wsc;
this.handshakeRequest = handshakeRequest;
this.negotiatedExtensions = negotiatedExtensionsPhase2;
this.subProtocol = subProtocol;
this.transformation = transformation;
this.pathParameters = pathParameters;
this.secure = secure;
}
@Override
public void init(WebConnection connection) {
this.connection = connection;
if (serverEndpointConfig == null) {
throw new IllegalStateException(sm.getString("wsHttpUpgradeHandler.noPreInit"));
}
String httpSessionId = null;
Object session = handshakeRequest.getHttpSession();
if (session != null) {
httpSessionId = ((HttpSession) session).getId();
}
// Need to call onOpen using the web application's class loader
// Create the frame using the application's class loader so it can pick
// up application specific config from the ServerContainerImpl
Thread t = Thread.currentThread();
ClassLoader cl = t.getContextClassLoader();
t.setContextClassLoader(applicationClassLoader);
try {
wsRemoteEndpointServer = new WsRemoteEndpointImplServer(socketWrapper, upgradeInfo, webSocketContainer,
connection);
wsSession = new WsSession(wsRemoteEndpointServer, webSocketContainer, handshakeRequest.getRequestURI(),
handshakeRequest.getParameterMap(), handshakeRequest.getQueryString(),
handshakeRequest.getUserPrincipal(), httpSessionId, negotiatedExtensions, subProtocol,
pathParameters, secure, serverEndpointConfig);
ep = wsSession.getLocal();
wsFrame = new WsFrameServer(socketWrapper, upgradeInfo, wsSession, transformation, applicationClassLoader);
// WsFrame adds the necessary final transformations. Copy the
// completed transformation chain to the remote end point.
wsRemoteEndpointServer.setTransformation(wsFrame.getTransformation());
ep.onOpen(wsSession, serverEndpointConfig);
webSocketContainer.registerSession(serverEndpointConfig.getPath(), wsSession);
} catch (DeploymentException e) {
throw new IllegalArgumentException(e);
} finally {
t.setContextClassLoader(cl);
}
}
@Override
public UpgradeInfo getUpgradeInfo() {
return upgradeInfo;
}
@Override
public SocketState upgradeDispatch(SocketEvent status) {
switch (status) {
case OPEN_READ:
try {
return wsFrame.notifyDataAvailable();
} catch (WsIOException ws) {
close(ws.getCloseReason());
} catch (IOException ioe) {
onError(ioe);
CloseReason cr = new CloseReason(CloseCodes.CLOSED_ABNORMALLY, ioe.getMessage());
close(cr);
}
return SocketState.CLOSED;
case OPEN_WRITE:
wsRemoteEndpointServer.onWritePossible(false);
break;
case STOP:
CloseReason cr = new CloseReason(CloseCodes.GOING_AWAY,
sm.getString("wsHttpUpgradeHandler.serverStop"));
try {
wsSession.close(cr);
} catch (IOException ioe) {
onError(ioe);
cr = new CloseReason(CloseCodes.CLOSED_ABNORMALLY, ioe.getMessage());
close(cr);
return SocketState.CLOSED;
}
break;
case ERROR:
// Need to clear any in-progress writes before trying to send a close frame
wsRemoteEndpointServer.clearHandler(socketWrapper.getError(), false);
String msg = sm.getString("wsHttpUpgradeHandler.closeOnError");
wsSession.doClose(new CloseReason(CloseCodes.GOING_AWAY, msg),
new CloseReason(CloseCodes.CLOSED_ABNORMALLY, msg));
//$FALL-THROUGH$
case DISCONNECT:
case TIMEOUT:
case CONNECT_FAIL:
return SocketState.CLOSED;
}
/*
* If a CLOSE frame has been received then wsFrame will be closed but need to keep the connection open until the
* CLOSE frame has been sent. Hence use the wsSession.isClosed() rather than wsFrame.isOpen() here.
*/
if (wsSession.isClosed()) {
return SocketState.CLOSED;
} else {
return SocketState.UPGRADED;
}
}
@Override
public void timeoutAsync(long now) {
// NO-OP
}
@Override
public void pause() {
// NO-OP
}
@Override
public void destroy() {
WebConnection connection = this.connection;
if (connection != null) {
this.connection = null;
try {
connection.close();
} catch (Exception e) {
log.error(sm.getString("wsHttpUpgradeHandler.destroyFailed"), e);
}
}
}
private void onError(Throwable throwable) {
// Need to call onError using the web application's class loader
Thread t = Thread.currentThread();
ClassLoader cl = t.getContextClassLoader();
t.setContextClassLoader(applicationClassLoader);
try {
ep.onError(wsSession, throwable);
} finally {
t.setContextClassLoader(cl);
}
}
private void close(CloseReason cr) {
/*
* Any call to this method is a result of a problem reading from the client. At this point that state of the
* connection is unknown. First attempt to clear the handler for any in-flight message write (that probably
* failed). If using NIO2 is is possible that the original error occurred on a write but this method was called
* during a read. The in-progress write will block the sending of the close frame unless the handler is cleared
* (effectively signalling the write failed).
*/
wsRemoteEndpointServer.clearHandler(new EOFException(), true);
/*
* Then: - send a close frame to the client - close the socket immediately. There is no point in waiting for a
* close frame from the client because there is no guarantee that we can recover from whatever messed up state
* the client put the connection into.
*/
wsSession.onClose(cr);
}
@Override
public void setSslSupport(SSLSupport sslSupport) {
// NO-OP. WebSocket has no requirement to access the TLS information
// associated with the underlying connection.
}
}