Http2ClientConnectionHandler.java Source code

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Here is the source code for Http2ClientConnectionHandler.java

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/*
 * 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.
 */

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.TimeUnit;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.handler.codec.http.DefaultFullHttpResponse;
import io.netty.handler.codec.http.FullHttpMessage;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.FullHttpResponse;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpVersion;
import io.netty.handler.codec.http2.AbstractHttp2ConnectionHandler;
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.DefaultHttp2InboundFlowController;
import io.netty.handler.codec.http2.DefaultHttp2OutboundFlowController;
import io.netty.handler.codec.http2.Http2Connection;
import io.netty.handler.codec.http2.Http2Exception;
import io.netty.handler.codec.http2.Http2FrameLogger;
import io.netty.handler.codec.http2.Http2Headers;
import io.netty.handler.codec.http2.Http2Settings;
import io.netty.util.concurrent.Promise;
import io.netty.util.internal.logging.InternalLoggerFactory;

import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;
import static io.netty.util.internal.logging.InternalLogLevel.INFO;

/**
 * A subclass of the connection handler that interprets response messages as text and prints it out
 * to the console.
 */
public class Http2ClientConnectionHandler extends AbstractHttp2ConnectionHandler {

    private static final Http2FrameLogger logger = new Http2FrameLogger(INFO,
            InternalLoggerFactory.getInstance(Http2ClientConnectionHandler.class));

    private final ChannelPromise initPromise;
    private ByteBuf collectedData;
    private ChannelHandlerContext ctx;
    private ConcurrentMap<Integer, OutstandingRequest> outstanding = new ConcurrentHashMap<>();

    private class OutstandingRequest {

        private HttpResponseStatus status;
        private Promise<FullHttpResponse> promise = ctx.executor().newPromise();
        private HttpVersion version = HTTP_1_1;

        public void finish(final ByteBuf content) {
            final FullHttpResponse response = new DefaultFullHttpResponse(version, status, content.retain());
            promise.setSuccess(response);
        }
    }

    public Http2ClientConnectionHandler(ChannelPromise initPromise) {
        this(initPromise, new DefaultHttp2Connection(false));
    }

    private Http2ClientConnectionHandler(ChannelPromise initPromise, Http2Connection connection) {
        super(connection, new DefaultHttp2FrameReader(), new DefaultHttp2FrameWriter(),
                new DefaultHttp2InboundFlowController(connection),
                new DefaultHttp2OutboundFlowController(connection));
        this.initPromise = initPromise;
    }

    /**
     * Wait for this handler to be added after the upgrade to HTTP/2, and for initial preface
     * handshake to complete.
     */
    public void awaitInitialization() throws Exception {
        if (!initPromise.awaitUninterruptibly(5, TimeUnit.SECONDS)) {
            throw new IllegalStateException("Timed out waiting for initialization");
        }
        if (!initPromise.isSuccess()) {
            throw new RuntimeException(initPromise.cause());
        }
    }

    /**
     * Handles conversion of a {@link FullHttpMessage} to HTTP/2 frames.
     */
    @Override
    public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
        if (msg instanceof FullHttpMessage) {
            FullHttpMessage httpMsg = (FullHttpMessage) msg;
            boolean hasData = httpMsg.content().isReadable();

            // Convert and write the headers.
            DefaultHttp2Headers.Builder headers = DefaultHttp2Headers.newBuilder();
            for (Map.Entry<String, String> entry : httpMsg.headers().entries()) {
                headers.add(entry.getKey(), entry.getValue());
            }
            int streamId = nextStreamId();
            writeHeaders(ctx, promise, streamId, headers.build(), 0, !hasData, false);
            if (hasData) {
                writeData(ctx, ctx.newPromise(), streamId, httpMsg.content(), 0, true, true);
            }
        } else {
            ctx.write(msg, promise);
        }
    }

    private volatile int streamIdCounter = 1;

    public Promise<FullHttpResponse> send(final FullHttpRequest request) {
        boolean hasData = request.content().isReadable();

        // Convert and write the headers.
        DefaultHttp2Headers.Builder headers = DefaultHttp2Headers.newBuilder();
        for (Map.Entry<String, String> entry : request.headers().entries()) {
            headers.add(entry.getKey(), entry.getValue());
        }
        synchronized (this) {
            streamIdCounter += 2;
            final int streamId = streamIdCounter;
            //      System.err.println("send: " + streamId);
            final OutstandingRequest outstandingRequest = new OutstandingRequest();
            outstanding.put(streamId, outstandingRequest);
            writeHeaders(ctx, ctx.newPromise(), streamId, headers.build(), 0, !hasData, false);
            if (hasData) {
                writeData(ctx, ctx.newPromise(), streamId, request.content(), 0, true, true);
            }
            return outstandingRequest.promise;
        }
    }

    @Override
    public void onDataRead(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding, boolean endOfStream,
            boolean endOfSegment) throws Http2Exception {

        // Copy the data into the buffer.
        int available = data.readableBytes();
        if (collectedData == null) {
            collectedData = ctx().alloc().buffer(available);
            collectedData.writeBytes(data, data.readerIndex(), data.readableBytes());
        } else {
            // Expand the buffer
            ByteBuf newBuffer = ctx().alloc().buffer(collectedData.readableBytes() + available);
            newBuffer.writeBytes(collectedData);
            newBuffer.writeBytes(data);
            collectedData.release();
            collectedData = newBuffer;
        }

        // If it's the last frame, print the complete message.
        if (endOfStream) {
            //      System.out.println("Received message: " + collectedData.toString(CharsetUtil.UTF_8));

            final OutstandingRequest outstandingRequest = outstanding.remove(streamId);
            outstandingRequest.finish(collectedData);

            // Free the data buffer.
            collectedData.release();
            collectedData = null;
        }
    }

    @Override
    public void onHeadersRead(ChannelHandlerContext ctx, int streamId, Http2Headers headers, int streamDependency,
            short weight, boolean exclusive, int padding, boolean endStream, boolean endSegment)
            throws Http2Exception {
        if (headers.contains(Http2ExampleUtil.UPGRADE_RESPONSE_HEADER)) {
            System.out.println("Received HTTP/2 response to the HTTP->HTTP/2 upgrade request");
        }
        final OutstandingRequest outstandingRequest = outstanding.get(streamId);
        if (outstandingRequest != null) {
            for (Map.Entry<String, String> entry : headers.entries()) {
                if (outstandingRequest.status == null && entry.getKey().equals(":status")) {
                    outstandingRequest.status = HttpResponseStatus.valueOf(Integer.valueOf(entry.getValue()));
                }
            }
        }
    }

    @Override
    public void onSettingsRead(ChannelHandlerContext ctx, Http2Settings settings) throws Http2Exception {
        this.ctx = ctx;
        if (!initPromise.isDone()) {
            initPromise.setSuccess();
        }
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        if (!initPromise.isDone()) {
            initPromise.setFailure(cause);
        }
        super.exceptionCaught(ctx, cause);
    }
}