org.apache.catalina.websocket.StreamInbound Maven / Gradle / Ivy
/*
* 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.catalina.websocket;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.nio.ByteBuffer;
import java.nio.charset.MalformedInputException;
import java.nio.charset.UnmappableCharacterException;
import org.apache.coyote.http11.upgrade.UpgradeInbound;
import org.apache.coyote.http11.upgrade.UpgradeOutbound;
import org.apache.coyote.http11.upgrade.UpgradeProcessor;
import org.apache.tomcat.util.net.AbstractEndpoint.Handler.SocketState;
/**
* Base implementation of the class used to process WebSocket connections based
* on streams. Applications should extend this class to provide application
* specific functionality. Applications that wish to operate on a message basis
* rather than a stream basis should use {@link MessageInbound}.
*/
public abstract class StreamInbound implements UpgradeInbound {
private final ClassLoader applicationClassLoader;
private UpgradeProcessor processor = null;
private WsOutbound outbound;
private int outboundByteBufferSize = WsOutbound.DEFAULT_BUFFER_SIZE;
private int outboundCharBufferSize = WsOutbound.DEFAULT_BUFFER_SIZE;
public StreamInbound() {
applicationClassLoader = Thread.currentThread().getContextClassLoader();
}
public int getOutboundByteBufferSize() {
return outboundByteBufferSize;
}
/**
* This only applies to the {@link WsOutbound} instance returned from
* {@link #getWsOutbound()} created by a subsequent call to
* {@link #setUpgradeOutbound(UpgradeOutbound)}. The current
* {@link WsOutbound} instance, if any, is not affected.
*
* @param outboundByteBufferSize
*/
public void setOutboundByteBufferSize(int outboundByteBufferSize) {
this.outboundByteBufferSize = outboundByteBufferSize;
}
public int getOutboundCharBufferSize() {
return outboundCharBufferSize;
}
/**
* This only applies to the {@link WsOutbound} instance returned from
* {@link #getWsOutbound()} created by a subsequent call to
* {@link #setUpgradeOutbound(UpgradeOutbound)}. The current
* {@link WsOutbound} instance, if any, is not affected.
*
* @param outboundCharBufferSize
*/
public void setOutboundCharBufferSize(int outboundCharBufferSize) {
this.outboundCharBufferSize = outboundCharBufferSize;
}
@Override
public final void setUpgradeOutbound(UpgradeOutbound upgradeOutbound) {
outbound = new WsOutbound(upgradeOutbound, outboundByteBufferSize,
outboundCharBufferSize);
}
@Override
public final void setUpgradeProcessor(UpgradeProcessor processor) {
this.processor = processor;
}
/**
* Obtain the outbound side of this WebSocket connection used for writing
* data to the client.
*/
public final WsOutbound getWsOutbound() {
return outbound;
}
@Override
public final SocketState onData() throws IOException {
// Must be start the start of a message (which may consist of multiple
// frames)
WsInputStream wsIs = new WsInputStream(processor, getWsOutbound());
try {
WsFrame frame = wsIs.nextFrame(true);
while (frame != null) {
// TODO User defined extensions may define values for rsv
if (frame.getRsv() > 0) {
closeOutboundConnection(
Constants.STATUS_PROTOCOL_ERROR, null);
return SocketState.CLOSED;
}
byte opCode = frame.getOpCode();
if (opCode == Constants.OPCODE_BINARY) {
doOnBinaryData(wsIs);
} else if (opCode == Constants.OPCODE_TEXT) {
InputStreamReader r =
new InputStreamReader(wsIs, new Utf8Decoder());
doOnTextData(r);
} else if (opCode == Constants.OPCODE_CLOSE){
closeOutboundConnection(frame);
return SocketState.CLOSED;
} else if (opCode == Constants.OPCODE_PING) {
getWsOutbound().pong(frame.getPayLoad());
} else if (opCode == Constants.OPCODE_PONG) {
// NO-OP
} else {
// Unknown OpCode
closeOutboundConnection(
Constants.STATUS_PROTOCOL_ERROR, null);
return SocketState.CLOSED;
}
frame = wsIs.nextFrame(false);
}
} catch (MalformedInputException mie) {
// Invalid UTF-8
closeOutboundConnection(Constants.STATUS_BAD_DATA, null);
return SocketState.CLOSED;
} catch (UnmappableCharacterException uce) {
// Invalid UTF-8
closeOutboundConnection(Constants.STATUS_BAD_DATA, null);
return SocketState.CLOSED;
} catch (IOException ioe) {
// Given something must have gone to reach this point, this
// might not work but try it anyway.
closeOutboundConnection(Constants.STATUS_PROTOCOL_ERROR, null);
return SocketState.CLOSED;
}
return SocketState.UPGRADED;
}
private void doOnBinaryData(InputStream is) throws IOException {
// Need to call onBinaryData using the web application's class loader
Thread t = Thread.currentThread();
ClassLoader cl = t.getContextClassLoader();
t.setContextClassLoader(applicationClassLoader);
try {
onBinaryData(is);
} finally {
t.setContextClassLoader(cl);
}
}
private void doOnTextData(Reader r) throws IOException {
// Need to call onTextData using the web application's class loader
Thread t = Thread.currentThread();
ClassLoader cl = t.getContextClassLoader();
t.setContextClassLoader(applicationClassLoader);
try {
onTextData(r);
} finally {
t.setContextClassLoader(cl);
}
}
private void closeOutboundConnection(int status, ByteBuffer data) throws IOException {
try {
getWsOutbound().close(status, data);
} finally {
doOnClose(status);
}
}
private void closeOutboundConnection(WsFrame frame) throws IOException {
try {
getWsOutbound().close(frame);
} finally {
doOnClose(Constants.STATUS_CLOSE_NORMAL);
}
}
private void doOnClose(int status) {
// Need to call onClose using the web application's class loader
Thread t = Thread.currentThread();
ClassLoader cl = t.getContextClassLoader();
t.setContextClassLoader(applicationClassLoader);
try {
onClose(status);
} finally {
t.setContextClassLoader(cl);
}
}
@Override
public final void onUpgradeComplete() {
// Need to call onOpen using the web application's class loader
Thread t = Thread.currentThread();
ClassLoader cl = t.getContextClassLoader();
t.setContextClassLoader(applicationClassLoader);
try {
onOpen(outbound);
} finally {
t.setContextClassLoader(cl);
}
}
/**
* Intended to be overridden by sub-classes that wish to be notified
* when the outbound connection is established. The default implementation
* is a NO-OP.
*
* @param outbound The outbound WebSocket connection.
*/
protected void onOpen(WsOutbound outbound) {
// NO-OP
}
/**
* Intended to be overridden by sub-classes that wish to be notified
* when the outbound connection is closed. The default implementation
* is a NO-OP.
*
* @param status The status code of the close reason.
*/
protected void onClose(int status) {
// NO-OP
}
/**
* This method is called when there is a binary WebSocket message available
* to process. The message is presented via a stream and may be formed from
* one or more frames. The number of frames used to transmit the message is
* not made visible to the application.
*
* @param is The WebSocket message
*
* @throws IOException If a problem occurs processing the message. Any
* exception will trigger the closing of the WebSocket
* connection.
*/
protected abstract void onBinaryData(InputStream is) throws IOException;
/**
* This method is called when there is a textual WebSocket message available
* to process. The message is presented via a reader and may be formed from
* one or more frames. The number of frames used to transmit the message is
* not made visible to the application.
*
* @param r The WebSocket message
*
* @throws IOException If a problem occurs processing the message. Any
* exception will trigger the closing of the WebSocket
* connection.
*/
protected abstract void onTextData(Reader r) throws IOException;
/**
* This default implementation sets the read timeout to infinite and expects
* the WebSocket application to close the connection when it is no longer
* required. Applications wishing to set an explicit timeout may override
* this method and return a value of their choice.
*
* @return The read timeout in milliseconds or -1 for infinite
*/
@Override
public int getReadTimeout() {
return -1;
}
}