/*
* Copyright 2014 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:
*
* 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 io.netty.example.http2.server;
import static io.netty.buffer.Unpooled.copiedBuffer;
import static io.netty.buffer.Unpooled.unreleasableBuffer;
import static io.netty.example.http2.Http2ExampleUtil.UPGRADE_RESPONSE_HEADER;
import static io.netty.util.internal.logging.InternalLogLevel.INFO;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.AsciiString;
import io.netty.handler.codec.http.HttpServerUpgradeHandler;
import io.netty.handler.codec.http2.DefaultHttp2Connection;
import io.netty.handler.codec.http2.DefaultHttp2FrameReader;
import io.netty.handler.codec.http2.DefaultHttp2FrameWriter;
import io.netty.handler.codec.http2.DefaultHttp2Headers;
import io.netty.handler.codec.http2.Http2Connection;
import io.netty.handler.codec.http2.Http2ConnectionEncoder;
import io.netty.handler.codec.http2.Http2ConnectionHandler;
import io.netty.handler.codec.http2.Http2Exception;
import io.netty.handler.codec.http2.Http2FrameAdapter;
import io.netty.handler.codec.http2.Http2FrameLogger;
import io.netty.handler.codec.http2.Http2FrameReader;
import io.netty.handler.codec.http2.Http2FrameWriter;
import io.netty.handler.codec.http2.Http2Headers;
import io.netty.handler.codec.http2.Http2InboundFrameLogger;
import io.netty.handler.codec.http2.Http2OutboundFrameLogger;
import io.netty.util.CharsetUtil;
import io.netty.util.internal.logging.InternalLoggerFactory;
/**
* A simple handler that responds with the message "Hello World!".
*/
public class HelloWorldHttp2Handler extends Http2ConnectionHandler {
private static final Http2FrameLogger logger = new Http2FrameLogger(INFO,
InternalLoggerFactory.getInstance(HelloWorldHttp2Handler.class));
static final ByteBuf RESPONSE_BYTES = unreleasableBuffer(copiedBuffer("Hello World", CharsetUtil.UTF_8));
public HelloWorldHttp2Handler() {
this(new DefaultHttp2Connection(true), new Http2InboundFrameLogger(
new DefaultHttp2FrameReader(), logger), new Http2OutboundFrameLogger(
new DefaultHttp2FrameWriter(), logger), new SimpleHttp2FrameListener());
}
private HelloWorldHttp2Handler(Http2Connection connection, Http2FrameReader frameReader,
Http2FrameWriter frameWriter, SimpleHttp2FrameListener listener) {
super(connection, frameReader, frameWriter, listener);
listener.encoder(encoder());
}
/**
* Handles the cleartext HTTP upgrade event. If an upgrade occurred, sends a simple response via HTTP/2
* on stream 1 (the stream specifically reserved for cleartext HTTP upgrade).
*/
@Override
public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
if (evt instanceof HttpServerUpgradeHandler.UpgradeEvent) {
// Write an HTTP/2 response to the upgrade request
Http2Headers headers =
new DefaultHttp2Headers().status(new AsciiString("200"))
.set(new AsciiString(UPGRADE_RESPONSE_HEADER), new AsciiString("true"));
encoder().writeHeaders(ctx, 1, headers, 0, true, ctx.newPromise());
}
super.userEventTriggered(ctx, evt);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
cause.printStackTrace();
ctx.close();
}
private static class SimpleHttp2FrameListener extends Http2FrameAdapter {
private Http2ConnectionEncoder encoder;
public void encoder(Http2ConnectionEncoder encoder) {
this.encoder = encoder;
}
/**
* If receive a frame with end-of-stream set, send a pre-canned response.
*/
@Override
public void onDataRead(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding,
boolean endOfStream) throws Http2Exception {
if (endOfStream) {
sendResponse(ctx, streamId, data.retain());
}
}
/**
* If receive a frame with end-of-stream set, send a pre-canned response.
*/
@Override
public void onHeadersRead(ChannelHandlerContext ctx, int streamId,
Http2Headers headers, int streamDependency, short weight,
boolean exclusive, int padding, boolean endStream) throws Http2Exception {
if (endStream) {
sendResponse(ctx, streamId, RESPONSE_BYTES.duplicate());
}
}
/**
* Sends a "Hello World" DATA frame to the client.
*/
private void sendResponse(ChannelHandlerContext ctx, int streamId, ByteBuf payload) {
// Send a frame for the response status
Http2Headers headers = new DefaultHttp2Headers().status(new AsciiString("200"));
encoder.writeHeaders(ctx, streamId, headers, 0, false, ctx.newPromise());
encoder.writeData(ctx, streamId, payload, 0, true, ctx.newPromise());
ctx.flush();
}
};
}