io.netty5.handler.codec.http.websocketx.WebSocketServerHandshaker Maven / Gradle / Ivy
/*
* Copyright 2019 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty5.handler.codec.http.websocketx;
import io.netty5.buffer.BufferAllocator;
import io.netty5.channel.Channel;
import io.netty5.channel.ChannelFutureListeners;
import io.netty5.channel.ChannelHandler;
import io.netty5.channel.ChannelHandlerAdapter;
import io.netty5.channel.ChannelHandlerContext;
import io.netty5.channel.ChannelOutboundInvoker;
import io.netty5.channel.ChannelPipeline;
import io.netty5.handler.codec.http.DefaultFullHttpRequest;
import io.netty5.handler.codec.http.FullHttpRequest;
import io.netty5.handler.codec.http.FullHttpResponse;
import io.netty5.handler.codec.http.HttpContentCompressor;
import io.netty5.handler.codec.http.HttpObject;
import io.netty5.handler.codec.http.HttpObjectAggregator;
import io.netty5.handler.codec.http.HttpRequest;
import io.netty5.handler.codec.http.HttpRequestDecoder;
import io.netty5.handler.codec.http.HttpResponseEncoder;
import io.netty5.handler.codec.http.HttpServerCodec;
import io.netty5.handler.codec.http.LastHttpContent;
import io.netty5.handler.codec.http.headers.HttpHeaders;
import io.netty5.util.ReferenceCountUtil;
import io.netty5.util.Resource;
import io.netty5.util.concurrent.Future;
import io.netty5.util.concurrent.Promise;
import io.netty5.util.internal.EmptyArrays;
import io.netty5.util.internal.logging.InternalLogger;
import io.netty5.util.internal.logging.InternalLoggerFactory;
import java.nio.channels.ClosedChannelException;
import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.Set;
import static java.util.Objects.requireNonNull;
/**
* Base class for server side web socket opening and closing handshakes
*/
public abstract class WebSocketServerHandshaker {
protected static final InternalLogger logger = InternalLoggerFactory.getInstance(WebSocketServerHandshaker.class);
private final String uri;
private final String[] subprotocols;
private final WebSocketVersion version;
private final WebSocketDecoderConfig decoderConfig;
private String selectedSubprotocol;
/**
* Use this as wildcard to support all requested sub-protocols
*/
public static final String SUB_PROTOCOL_WILDCARD = "*";
/**
* Constructor specifying the destination web socket location
*
* @param version the protocol version
* @param uri URL for web socket communications. e.g "ws://myhost.com/mypath".
* Subsequent web socket frames will be sent to this URL.
* @param subprotocols CSV of supported protocols. Null if sub protocols not supported.
* @param maxFramePayloadLength Maximum length of a frame's payload
*/
protected WebSocketServerHandshaker(
WebSocketVersion version, String uri, String subprotocols,
int maxFramePayloadLength) {
this(version, uri, subprotocols, WebSocketDecoderConfig.newBuilder()
.maxFramePayloadLength(maxFramePayloadLength)
.build());
}
/**
* Constructor specifying the destination web socket location
*
* @param version the protocol version
* @param uri URL for web socket communications. e.g "ws://myhost.com/mypath".
* Subsequent web socket frames will be sent to this URL.
* @param subprotocols CSV of supported protocols. Null if sub protocols not supported.
* @param decoderConfig Frames decoder configuration.
*/
protected WebSocketServerHandshaker(
WebSocketVersion version, String uri, String subprotocols, WebSocketDecoderConfig decoderConfig) {
this.version = version;
this.uri = uri;
if (subprotocols != null) {
String[] subprotocolArray = subprotocols.split(",");
for (int i = 0; i < subprotocolArray.length; i++) {
subprotocolArray[i] = subprotocolArray[i].trim();
}
this.subprotocols = subprotocolArray;
} else {
this.subprotocols = EmptyArrays.EMPTY_STRINGS;
}
this.decoderConfig = requireNonNull(decoderConfig, "decoderConfig");
}
/**
* Returns the URL of the web socket
*/
public String uri() {
return uri;
}
/**
* Returns the CSV of supported sub protocols
*/
public Set subprotocols() {
Set ret = new LinkedHashSet<>();
Collections.addAll(ret, subprotocols);
return ret;
}
/**
* Returns the version of the specification being supported
*/
public WebSocketVersion version() {
return version;
}
/**
* Gets the maximum length for any frame's payload.
*
* @return The maximum length for a frame's payload
*/
public int maxFramePayloadLength() {
return decoderConfig.maxFramePayloadLength();
}
/**
* Gets this decoder configuration.
*
* @return This decoder configuration.
*/
public WebSocketDecoderConfig decoderConfig() {
return decoderConfig;
}
/**
* Performs the opening handshake. Note that the ownership of the {@link FullHttpRequest} which is passed in
* belongs to the caller (ownership is not transferred to this method, and caller is responsible
* to close the request parameter).
*
* @param channel Channel
* @param req HTTP Request
* @return future
* The {@link Future} which is notified once the opening handshake completes
*/
public Future handshake(Channel channel, FullHttpRequest req) {
return handshake(channel, req, null);
}
/**
* Performs the opening handshake
*
* Note that the ownership of the {@link FullHttpRequest} which is passed in
* belongs to the caller (ownership is not transferred to this method, and caller is responsible
* to close the request parameter).
*
* @param channel Channel
* @param req HTTP Request
* @param responseHeaders Extra headers to add to the handshake response or {@code null}
* if no extra headers should be added
* @return future
* the {@link Future} which is notified when the opening handshake is done
*/
public final Future handshake(Channel channel, FullHttpRequest req, HttpHeaders responseHeaders) {
if (logger.isDebugEnabled()) {
logger.debug("{} WebSocket version {} server handshake", channel, version());
}
FullHttpResponse response = newHandshakeResponse(channel.bufferAllocator(), req, responseHeaders);
ChannelPipeline p = channel.pipeline();
if (p.get(HttpObjectAggregator.class) != null) {
p.remove(HttpObjectAggregator.class);
}
if (p.get(HttpContentCompressor.class) != null) {
p.remove(HttpContentCompressor.class);
}
ChannelHandlerContext ctx = p.context(HttpRequestDecoder.class);
final String encoderName;
if (ctx == null) {
// this means the user use an HttpServerCodec
ctx = p.context(HttpServerCodec.class);
if (ctx == null) {
return channel.newFailedFuture(
new IllegalStateException("No HttpDecoder and no HttpServerCodec in the pipeline"));
}
p.addBefore(ctx.name(), "wsencoder", newWebSocketEncoder());
p.addBefore(ctx.name(), "wsdecoder", newWebsocketDecoder());
encoderName = ctx.name();
} else {
p.replace(ctx.name(), "wsdecoder", newWebsocketDecoder());
encoderName = p.context(HttpResponseEncoder.class).name();
p.addBefore(encoderName, "wsencoder", newWebSocketEncoder());
}
return channel.writeAndFlush(response).addListener(channel, (ch, future) -> {
if (future.isSuccess()) {
ChannelPipeline p1 = ch.pipeline();
p1.remove(encoderName);
}
});
}
/**
* Performs the opening handshake. Note that the ownership of the {@link FullHttpRequest} which is passed in
* belongs to the caller (ownership is not transferred to this method, and caller is responsible
* to close the request parameter).
*
* @param channel Channel
* @param req HTTP Request
* @return future
* The {@link Future} which is notified once the opening handshake completes
*/
public Future handshake(Channel channel, HttpRequest req) {
return handshake(channel, req, null);
}
/**
* Performs the opening handshake
*
* Note that the ownership of the {@link FullHttpRequest} which is passed in
* belongs to the caller (ownership is not transferred to this method, and caller is responsible
* to close the request parameter).
*
* @param channel Channel
* @param req HTTP Request
* @param responseHeaders Extra headers to add to the handshake response or {@code null}
* if no extra headers should be added
* @return future
* the {@link Future} which is notified when the opening handshake is done
*/
public final Future handshake(final Channel channel, HttpRequest req,
final HttpHeaders responseHeaders) {
if (req instanceof FullHttpRequest) {
return handshake(channel, (FullHttpRequest) req, responseHeaders);
}
ChannelPipeline pipeline = channel.pipeline();
ChannelHandlerContext ctx = pipeline.context(HttpRequestDecoder.class);
if (ctx == null) {
// This means the user use a HttpServerCodec
ctx = pipeline.context(HttpServerCodec.class);
if (ctx == null) {
return channel.newFailedFuture(
new IllegalStateException("No HttpDecoder and no HttpServerCodec in the pipeline"));
}
}
final Promise promise = channel.newPromise();
pipeline.addAfter(ctx.name(), "handshaker", new ChannelHandlerAdapter() {
private FullHttpRequest fullHttpRequest;
@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
if (msg instanceof HttpObject) {
try {
handleHandshakeRequest(ctx, (HttpObject) msg);
} finally {
Resource.dispose(msg);
}
} else {
super.channelRead(ctx, msg);
}
}
@Override
public void channelExceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
ctx.pipeline().remove(this);
promise.tryFailure(cause);
super.channelExceptionCaught(ctx, cause);
}
@Override
public void channelInactive(ChannelHandlerContext ctx) throws Exception {
try {
// Fail promise if Channel was closed
if (!promise.isDone()) {
promise.tryFailure(new ClosedChannelException());
}
ctx.fireChannelInactive();
} finally {
releaseFullHttpRequest();
}
}
@Override
public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
releaseFullHttpRequest();
}
private void handleHandshakeRequest(ChannelHandlerContext ctx, HttpObject httpObject) {
if (httpObject instanceof FullHttpRequest) {
ctx.pipeline().remove(this);
handshake(channel, (FullHttpRequest) httpObject, responseHeaders).cascadeTo(promise);
return;
}
if (httpObject instanceof LastHttpContent) {
assert fullHttpRequest != null;
try (FullHttpRequest handshakeRequest = fullHttpRequest) {
fullHttpRequest = null;
ctx.pipeline().remove(this);
handshake(channel, handshakeRequest, responseHeaders).cascadeTo(promise);
}
return;
}
if (httpObject instanceof HttpRequest) {
HttpRequest httpRequest = (HttpRequest) httpObject;
fullHttpRequest = new DefaultFullHttpRequest(httpRequest.protocolVersion(), httpRequest.method(),
httpRequest.uri(), ctx.bufferAllocator().allocate(0),
httpRequest.headers(), HttpHeaders.emptyHeaders());
if (httpRequest.decoderResult().isFailure()) {
fullHttpRequest.setDecoderResult(httpRequest.decoderResult());
}
}
}
private void releaseFullHttpRequest() {
if (fullHttpRequest != null) {
fullHttpRequest.close();
fullHttpRequest = null;
}
}
});
try {
ctx.fireChannelRead(ReferenceCountUtil.retain(req));
} catch (Throwable cause) {
promise.setFailure(cause);
}
return promise.asFuture();
}
/**
* Returns a new {@link FullHttpResponse) which will be used for as response to the handshake request.
*/
protected abstract FullHttpResponse newHandshakeResponse(BufferAllocator allocator, FullHttpRequest req,
HttpHeaders responseHeaders);
/**
* Performs the closing handshake.
*
* When called from within a {@link ChannelHandler} you most likely want to use
* {@link #close(ChannelHandlerContext, CloseWebSocketFrame)}.
*
* @param channel the {@link Channel} to use.
* @param frame Closing Frame that was received.
*/
public Future close(Channel channel, CloseWebSocketFrame frame) {
requireNonNull(channel, "channel");
return close0(channel, frame);
}
/**
* Performs the closing handshake.
*
* @param ctx the {@link ChannelHandlerContext} to use.
* @param frame Closing Frame that was received.
*/
public Future close(ChannelHandlerContext ctx, CloseWebSocketFrame frame) {
requireNonNull(ctx, "ctx");
return close0(ctx, frame);
}
private static Future close0(ChannelOutboundInvoker invoker, CloseWebSocketFrame frame) {
return invoker.writeAndFlush(frame).addListener(invoker, ChannelFutureListeners.CLOSE);
}
/**
* Selects the first matching supported sub protocol
*
* @param requestedSubprotocols CSV of protocols to be supported. e.g. "chat, superchat"
* @return First matching supported sub protocol. Null if not found.
*/
protected String selectSubprotocol(String requestedSubprotocols) {
if (requestedSubprotocols == null || subprotocols.length == 0) {
return null;
}
String[] requestedSubprotocolArray = requestedSubprotocols.split(",");
for (String p : requestedSubprotocolArray) {
String requestedSubprotocol = p.trim();
for (String supportedSubprotocol : subprotocols) {
if (SUB_PROTOCOL_WILDCARD.equals(supportedSubprotocol)
|| requestedSubprotocol.equals(supportedSubprotocol)) {
selectedSubprotocol = requestedSubprotocol;
return requestedSubprotocol;
}
}
}
// No match found
return null;
}
/**
* Returns the selected subprotocol. Null if no subprotocol has been selected.
*
* This is only available AFTER handshake() has been called.
*
*/
public String selectedSubprotocol() {
return selectedSubprotocol;
}
/**
* Returns the decoder to use after handshake is complete.
*/
protected abstract WebSocketFrameDecoder newWebsocketDecoder();
/**
* Returns the encoder to use after the handshake is complete.
*/
protected abstract WebSocketFrameEncoder newWebSocketEncoder();
}