| /** |
| * 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.hadoop.hdfs.server.datanode.web; |
| |
| import io.netty.bootstrap.Bootstrap; |
| import io.netty.buffer.Unpooled; |
| import io.netty.channel.Channel; |
| import io.netty.channel.ChannelFuture; |
| import io.netty.channel.ChannelFutureListener; |
| import io.netty.channel.ChannelHandlerContext; |
| import io.netty.channel.ChannelInboundHandlerAdapter; |
| import io.netty.channel.ChannelInitializer; |
| import io.netty.channel.ChannelPipeline; |
| import io.netty.channel.SimpleChannelInboundHandler; |
| import io.netty.channel.socket.SocketChannel; |
| import io.netty.channel.socket.nio.NioSocketChannel; |
| import io.netty.handler.codec.http.DefaultFullHttpRequest; |
| import io.netty.handler.codec.http.DefaultHttpResponse; |
| import io.netty.handler.codec.http.HttpRequest; |
| import io.netty.handler.codec.http.HttpRequestEncoder; |
| import io.netty.handler.codec.http.HttpResponseEncoder; |
| import org.apache.commons.logging.Log; |
| |
| import java.net.InetSocketAddress; |
| |
| import static io.netty.handler.codec.http.HttpHeaders.Names.CONNECTION; |
| import static io.netty.handler.codec.http.HttpHeaders.Values; |
| import static io.netty.handler.codec.http.HttpResponseStatus.INTERNAL_SERVER_ERROR; |
| import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1; |
| |
| /** |
| * Dead simple session-layer HTTP proxy. It gets the HTTP responses |
| * inside the context, assuming that the remote peer is reasonable fast and |
| * the response is small. The upper layer should be filtering out malicious |
| * inputs. |
| */ |
| class SimpleHttpProxyHandler extends SimpleChannelInboundHandler<HttpRequest> { |
| private String uri; |
| private Channel proxiedChannel; |
| private final InetSocketAddress host; |
| static final Log LOG = DatanodeHttpServer.LOG; |
| |
| SimpleHttpProxyHandler(InetSocketAddress host) { |
| this.host = host; |
| } |
| |
| private static class Forwarder extends ChannelInboundHandlerAdapter { |
| private final String uri; |
| private final Channel client; |
| |
| private Forwarder(String uri, Channel client) { |
| this.uri = uri; |
| this.client = client; |
| } |
| |
| @Override |
| public void channelInactive(ChannelHandlerContext ctx) { |
| closeOnFlush(client); |
| } |
| |
| @Override |
| public void channelRead(final ChannelHandlerContext ctx, Object msg) { |
| client.writeAndFlush(msg).addListener(new ChannelFutureListener() { |
| @Override |
| public void operationComplete(ChannelFuture future) { |
| if (future.isSuccess()) { |
| ctx.channel().read(); |
| } else { |
| LOG.debug("Proxy failed. Cause: ", future.cause()); |
| future.channel().close(); |
| } |
| } |
| }); |
| } |
| |
| @Override |
| public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { |
| LOG.debug("Proxy for " + uri + " failed. cause: ", cause); |
| closeOnFlush(ctx.channel()); |
| } |
| } |
| |
| @Override |
| public void channelRead0 |
| (final ChannelHandlerContext ctx, final HttpRequest req) { |
| uri = req.getUri(); |
| final Channel client = ctx.channel(); |
| Bootstrap proxiedServer = new Bootstrap() |
| .group(client.eventLoop()) |
| .channel(NioSocketChannel.class) |
| .handler(new ChannelInitializer<SocketChannel>() { |
| @Override |
| protected void initChannel(SocketChannel ch) throws Exception { |
| ChannelPipeline p = ch.pipeline(); |
| p.addLast(new HttpRequestEncoder(), new Forwarder(uri, client)); |
| } |
| }); |
| ChannelFuture f = proxiedServer.connect(host); |
| proxiedChannel = f.channel(); |
| f.addListener(new ChannelFutureListener() { |
| @Override |
| public void operationComplete(ChannelFuture future) throws Exception { |
| if (future.isSuccess()) { |
| ctx.channel().pipeline().remove(HttpResponseEncoder.class); |
| HttpRequest newReq = new DefaultFullHttpRequest(HTTP_1_1, |
| req.getMethod(), req.getUri()); |
| newReq.headers().add(req.headers()); |
| newReq.headers().set(CONNECTION, Values.CLOSE); |
| future.channel().writeAndFlush(newReq); |
| } else { |
| DefaultHttpResponse resp = new DefaultHttpResponse(HTTP_1_1, |
| INTERNAL_SERVER_ERROR); |
| resp.headers().set(CONNECTION, Values.CLOSE); |
| LOG.info("Proxy " + uri + " failed. Cause: ", future.cause()); |
| ctx.writeAndFlush(resp).addListener(ChannelFutureListener.CLOSE); |
| client.close(); |
| } |
| } |
| }); |
| } |
| |
| @Override |
| public void channelInactive(ChannelHandlerContext ctx) { |
| if (proxiedChannel != null) { |
| proxiedChannel.close(); |
| proxiedChannel = null; |
| } |
| } |
| |
| @Override |
| public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Proxy for " + uri + " failed. cause: ", cause); |
| } |
| if (proxiedChannel != null) { |
| proxiedChannel.close(); |
| proxiedChannel = null; |
| } |
| ctx.close(); |
| } |
| |
| private static void closeOnFlush(Channel ch) { |
| if (ch.isActive()) { |
| ch.writeAndFlush(Unpooled.EMPTY_BUFFER) |
| .addListener(ChannelFutureListener.CLOSE); |
| } |
| } |
| } |