View Javadoc
1   /*
2    * Copyright 2012 The Netty Project
3    *
4    * The Netty Project licenses this file to you under the Apache License,
5    * version 2.0 (the "License"); you may not use this file except in compliance
6    * with the License. You may obtain a copy of the License at:
7    *
8    *   http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13   * License for the specific language governing permissions and limitations
14   * under the License.
15   */
16  package io.netty.example.http.websocketx.server;
17  
18  import io.netty.buffer.ByteBuf;
19  import io.netty.buffer.Unpooled;
20  import io.netty.channel.ChannelFuture;
21  import io.netty.channel.ChannelFutureListener;
22  import io.netty.channel.ChannelHandlerContext;
23  import io.netty.channel.ChannelPipeline;
24  import io.netty.channel.SimpleChannelInboundHandler;
25  import io.netty.handler.codec.http.DefaultFullHttpResponse;
26  import io.netty.handler.codec.http.FullHttpRequest;
27  import io.netty.handler.codec.http.FullHttpResponse;
28  import io.netty.handler.codec.http.HttpHeaders;
29  import io.netty.handler.codec.http.HttpRequest;
30  import io.netty.handler.ssl.SslHandler;
31  import io.netty.util.CharsetUtil;
32  
33  import static io.netty.handler.codec.http.HttpMethod.GET;
34  import static io.netty.handler.codec.http.HttpResponseStatus.BAD_REQUEST;
35  import static io.netty.handler.codec.http.HttpResponseStatus.FORBIDDEN;
36  import static io.netty.handler.codec.http.HttpResponseStatus.NOT_FOUND;
37  import static io.netty.handler.codec.http.HttpResponseStatus.OK;
38  import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1;
39  
40  /**
41   * Outputs index page content.
42   */
43  public class WebSocketIndexPageHandler extends SimpleChannelInboundHandler<FullHttpRequest> {
44  
45      private final String websocketPath;
46  
47      public WebSocketIndexPageHandler(String websocketPath) {
48          this.websocketPath = websocketPath;
49      }
50  
51      @Override
52      protected void channelRead0(ChannelHandlerContext ctx, FullHttpRequest req) throws Exception {
53          // Handle a bad request.
54          if (!req.getDecoderResult().isSuccess()) {
55              sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, BAD_REQUEST));
56              return;
57          }
58  
59          // Allow only GET methods.
60          if (req.getMethod() != GET) {
61              sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, FORBIDDEN));
62              return;
63          }
64  
65          // Send the index page
66          if ("/".equals(req.getUri()) || "/index.html".equals(req.getUri())) {
67              String webSocketLocation = getWebSocketLocation(ctx.pipeline(), req, websocketPath);
68              ByteBuf content = WebSocketServerIndexPage.getContent(webSocketLocation);
69              FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, content);
70  
71              res.headers().set(HttpHeaders.Names.CONTENT_TYPE, "text/html; charset=UTF-8");
72              HttpHeaders.setContentLength(res, content.readableBytes());
73  
74              sendHttpResponse(ctx, req, res);
75          } else {
76              sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND));
77          }
78      }
79  
80      @Override
81      public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
82          cause.printStackTrace();
83          ctx.close();
84      }
85  
86      private static void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, FullHttpResponse res) {
87          // Generate an error page if response getStatus code is not OK (200).
88          if (res.getStatus().code() != 200) {
89              ByteBuf buf = Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8);
90              res.content().writeBytes(buf);
91              buf.release();
92              HttpHeaders.setContentLength(res, res.content().readableBytes());
93          }
94  
95          // Send the response and close the connection if necessary.
96          ChannelFuture f = ctx.channel().writeAndFlush(res);
97          if (!HttpHeaders.isKeepAlive(req) || res.getStatus().code() != 200) {
98              f.addListener(ChannelFutureListener.CLOSE);
99          }
100     }
101 
102     private static String getWebSocketLocation(ChannelPipeline cp, HttpRequest req, String path) {
103         String protocol = "ws";
104         if (cp.get(SslHandler.class) != null) {
105             // SSL in use so use Secure WebSockets
106             protocol = "wss";
107         }
108         return protocol + "://" + req.headers().get(HttpHeaders.Names.HOST) + path;
109     }
110 }