1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27
28 package org.apache.hc.core5.http.io.support;
29
30 import java.io.IOException;
31
32 import org.apache.hc.core5.http.ClassicHttpRequest;
33 import org.apache.hc.core5.http.ClassicHttpResponse;
34 import org.apache.hc.core5.http.HttpException;
35 import org.apache.hc.core5.http.HttpStatus;
36 import org.apache.hc.core5.http.io.HttpServerRequestHandler;
37 import org.apache.hc.core5.http.message.BasicClassicHttpResponse;
38 import org.apache.hc.core5.http.support.ExpectSupport;
39 import org.apache.hc.core5.http.support.Expectation;
40 import org.apache.hc.core5.http.protocol.HttpContext;
41 import org.apache.hc.core5.util.Args;
42
43 /**
44 * {@link HttpServerRequestHandler} implementation that adds support
45 * for the Expect-Continue handshake to an existing
46 * {@link HttpServerRequestHandler}.
47 *
48 * @since 5.0
49 */
50 public class BasicHttpServerExpectationDecorator implements HttpServerRequestHandler {
51
52 private final HttpServerRequestHandler requestHandler;
53
54 public BasicHttpServerExpectationDecorator(final HttpServerRequestHandler requestHandler) {
55 this.requestHandler = Args.notNull(requestHandler, "Request handler");
56 }
57
58 /**
59 * Verifies the HTTP request and decides whether it meets server expectations and the request
60 * processing can continue.
61 *
62 * @param request the incoming HTTP request.
63 * @param context the actual execution context.
64 * @return {@code null} if the request meets expectations or a final HTTP response
65 * with an error status representing the cause of expectation failure.
66 */
67 protected ClassicHttpResponse verify(final ClassicHttpRequest request, final HttpContext context) {
68 return null;
69 }
70
71 @Override
72 public final void handle(
73 final ClassicHttpRequest request,
74 final ResponseTrigger responseTrigger,
75 final HttpContext context) throws HttpException, IOException {
76 final Expectation expectation = ExpectSupport.parse(request, request.getEntity());
77 if (expectation == Expectation.CONTINUE) {
78 final ClassicHttpResponse response = verify(request, context);
79 if (response == null) {
80 responseTrigger.sendInformation(new BasicClassicHttpResponse(HttpStatus.SC_CONTINUE));
81 } else {
82 responseTrigger.submitResponse(response);
83 return;
84 }
85 } else if (expectation == Expectation.UNKNOWN) {
86 final ClassicHttpResponse expectationFailed = new BasicClassicHttpResponse(HttpStatus.SC_EXPECTATION_FAILED);
87 responseTrigger.submitResponse(expectationFailed);
88 return;
89 }
90 requestHandler.handle(request, responseTrigger, context);
91 }
92
93 }