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.protocol;
29
30 import java.io.IOException;
31
32 import org.apache.hc.core5.annotation.Contract;
33 import org.apache.hc.core5.annotation.ThreadingBehavior;
34 import org.apache.hc.core5.http.EntityDetails;
35 import org.apache.hc.core5.http.Header;
36 import org.apache.hc.core5.http.HeaderElements;
37 import org.apache.hc.core5.http.HttpException;
38 import org.apache.hc.core5.http.HttpHeaders;
39 import org.apache.hc.core5.http.HttpRequest;
40 import org.apache.hc.core5.http.HttpRequestInterceptor;
41 import org.apache.hc.core5.http.HttpVersion;
42 import org.apache.hc.core5.http.Method;
43 import org.apache.hc.core5.http.ProtocolException;
44 import org.apache.hc.core5.http.ProtocolVersion;
45 import org.apache.hc.core5.http.message.MessageSupport;
46 import org.apache.hc.core5.util.Args;
47
48 /**
49 * This request interceptor is responsible for delimiting the message content
50 * by adding {@code Content-Length} or {@code Transfer-Content} headers based
51 * on the properties of the enclosed entity and the protocol version.
52 * <p>
53 * This interceptor is essential for the HTTP protocol conformance and
54 * the correct operation of the client-side message processing pipeline.
55 * </p>
56 *
57 * @since 4.0
58 */
59 @Contract(threading = ThreadingBehavior.IMMUTABLE)
60 public class RequestContent implements HttpRequestInterceptor {
61
62 /**
63 * Singleton instance.
64 * @since 5.2
65 */
66 public static final HttpRequestInterceptor INSTANCE = new RequestContent();
67
68 private final boolean overwrite;
69
70 /**
71 * Default constructor. The {@code Content-Length} or {@code Transfer-Encoding}
72 * will cause the interceptor to throw {@link ProtocolException} if already present in the
73 * response message.
74 */
75 public RequestContent() {
76 this(false);
77 }
78
79 /**
80 * Constructor that can be used to fine-tune behavior of this interceptor.
81 *
82 * @param overwrite If set to {@code true} the {@code Content-Length} and
83 * {@code Transfer-Encoding} headers will be created or updated if already present.
84 * If set to {@code false} the {@code Content-Length} and
85 * {@code Transfer-Encoding} headers will cause the interceptor to throw
86 * {@link ProtocolException} if already present in the response message.
87 *
88 * @since 4.2
89 */
90 public RequestContent(final boolean overwrite) {
91 super();
92 this.overwrite = overwrite;
93 }
94
95 @Override
96 public void process(final HttpRequest request, final EntityDetails entity, final HttpContext context)
97 throws HttpException, IOException {
98 Args.notNull(request, "HTTP request");
99 final String method = request.getMethod();
100 if (Method.TRACE.isSame(method) && entity != null) {
101 throw new ProtocolException("TRACE request may not enclose an entity");
102 }
103 if (this.overwrite) {
104 request.removeHeaders(HttpHeaders.TRANSFER_ENCODING);
105 request.removeHeaders(HttpHeaders.CONTENT_LENGTH);
106 } else {
107 if (request.containsHeader(HttpHeaders.TRANSFER_ENCODING)) {
108 throw new ProtocolException("Transfer-encoding header already present");
109 }
110 if (request.containsHeader(HttpHeaders.CONTENT_LENGTH)) {
111 throw new ProtocolException("Content-Length header already present");
112 }
113 }
114 if (entity == null && isContentEnclosingMethod(method)) {
115 request.addHeader(HttpHeaders.CONTENT_LENGTH, "0");
116 return;
117 }
118 if (entity != null) {
119
120 // Check for OPTIONS request with content but no Content-Type header
121 validateOptionsContentType(request);
122
123 final ProtocolVersion ver = context.getProtocolVersion();
124 // Must specify a transfer encoding or a content length
125 if (entity.isChunked() || entity.getContentLength() < 0) {
126 if (ver.lessEquals(HttpVersion.HTTP_1_0)) {
127 throw new ProtocolException(
128 "Chunked transfer encoding not allowed for " + ver);
129 }
130 request.addHeader(HttpHeaders.TRANSFER_ENCODING, HeaderElements.CHUNKED_ENCODING);
131 MessageSupport.addTrailerHeader(request, entity);
132 } else {
133 request.addHeader(HttpHeaders.CONTENT_LENGTH, Long.toString(entity.getContentLength()));
134 }
135 MessageSupport.addContentTypeHeader(request, entity);
136 MessageSupport.addContentEncodingHeader(request, entity);
137 }
138 }
139 private boolean isContentEnclosingMethod(final String method) {
140 return (Method.POST.isSame(method)||Method.PUT.isSame(method)||Method.PATCH.isSame(method));
141 }
142 /**
143 * Validates the presence of the Content-Type header for an OPTIONS request.
144 *
145 * <p>
146 * According to the RFC specifications, an HTTP {@link Method#OPTIONS} request that contains content
147 * must have a Content-Type header. This method checks for the presence of the Content-Type header
148 * in such requests. It does not validate the actual value of the Content-Type header, as determining
149 * its validity would require knowledge of all valid media types, which is beyond the scope of this method.
150 * If the header is absent, a {@link ProtocolException} is thrown.
151 * </p>
152 *
153 * <p>
154 * Note: This method does not check the validity of the Content-Type header value, only its presence.
155 * </p>
156 *
157 * @param request The {@link HttpRequest} to be validated for the presence of the Content-Type header. Must not be null.
158 * @throws ProtocolException If the Content-Type header is missing in an OPTIONS request with content.
159 */
160 public void validateOptionsContentType(final HttpRequest request) throws ProtocolException {
161 if (Method.OPTIONS.isSame(request.getMethod())) {
162 final Header header = request.getFirstHeader(HttpHeaders.CONTENT_TYPE);
163 if (header == null) {
164 throw new ProtocolException("OPTIONS request must have Content-Type header");
165 }
166 }
167 }
168 }