RequestContent.java
/*
* ====================================================================
* 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.hc.core5.http.protocol;
import java.io.IOException;
import org.apache.hc.core5.annotation.Contract;
import org.apache.hc.core5.annotation.ThreadingBehavior;
import org.apache.hc.core5.http.EntityDetails;
import org.apache.hc.core5.http.Header;
import org.apache.hc.core5.http.HeaderElements;
import org.apache.hc.core5.http.HttpException;
import org.apache.hc.core5.http.HttpHeaders;
import org.apache.hc.core5.http.HttpRequest;
import org.apache.hc.core5.http.HttpRequestInterceptor;
import org.apache.hc.core5.http.HttpVersion;
import org.apache.hc.core5.http.Method;
import org.apache.hc.core5.http.ProtocolException;
import org.apache.hc.core5.http.ProtocolVersion;
import org.apache.hc.core5.http.message.MessageSupport;
import org.apache.hc.core5.util.Args;
/**
* This request interceptor is responsible for delimiting the message content
* by adding {@code Content-Length} or {@code Transfer-Content} headers based
* on the properties of the enclosed entity and the protocol version.
* <p>
* This interceptor is essential for the HTTP protocol conformance and
* the correct operation of the client-side message processing pipeline.
* </p>
*
* @since 4.0
*/
@Contract(threading = ThreadingBehavior.IMMUTABLE)
public class RequestContent implements HttpRequestInterceptor {
/**
* Singleton instance.
* @since 5.2
*/
public static final HttpRequestInterceptor INSTANCE = new RequestContent();
private final boolean overwrite;
/**
* Default constructor. The {@code Content-Length} or {@code Transfer-Encoding}
* will cause the interceptor to throw {@link ProtocolException} if already present in the
* response message.
*/
public RequestContent() {
this(false);
}
/**
* Constructor that can be used to fine-tune behavior of this interceptor.
*
* @param overwrite If set to {@code true} the {@code Content-Length} and
* {@code Transfer-Encoding} headers will be created or updated if already present.
* If set to {@code false} the {@code Content-Length} and
* {@code Transfer-Encoding} headers will cause the interceptor to throw
* {@link ProtocolException} if already present in the response message.
*
* @since 4.2
*/
public RequestContent(final boolean overwrite) {
super();
this.overwrite = overwrite;
}
@Override
public void process(final HttpRequest request, final EntityDetails entity, final HttpContext context)
throws HttpException, IOException {
Args.notNull(request, "HTTP request");
final String method = request.getMethod();
if (Method.TRACE.isSame(method) && entity != null) {
throw new ProtocolException("TRACE request may not enclose an entity");
}
if (this.overwrite) {
request.removeHeaders(HttpHeaders.TRANSFER_ENCODING);
request.removeHeaders(HttpHeaders.CONTENT_LENGTH);
} else {
if (request.containsHeader(HttpHeaders.TRANSFER_ENCODING)) {
throw new ProtocolException("Transfer-encoding header already present");
}
if (request.containsHeader(HttpHeaders.CONTENT_LENGTH)) {
throw new ProtocolException("Content-Length header already present");
}
}
if (entity == null && isContentEnclosingMethod(method)) {
request.addHeader(HttpHeaders.CONTENT_LENGTH, "0");
return;
}
if (entity != null) {
// Check for OPTIONS request with content but no Content-Type header
validateOptionsContentType(request);
final ProtocolVersion ver = context.getProtocolVersion();
// Must specify a transfer encoding or a content length
if (entity.isChunked() || entity.getContentLength() < 0) {
if (ver.lessEquals(HttpVersion.HTTP_1_0)) {
throw new ProtocolException(
"Chunked transfer encoding not allowed for " + ver);
}
request.addHeader(HttpHeaders.TRANSFER_ENCODING, HeaderElements.CHUNKED_ENCODING);
MessageSupport.addTrailerHeader(request, entity);
} else {
request.addHeader(HttpHeaders.CONTENT_LENGTH, Long.toString(entity.getContentLength()));
}
MessageSupport.addContentTypeHeader(request, entity);
MessageSupport.addContentEncodingHeader(request, entity);
}
}
private boolean isContentEnclosingMethod(final String method) {
return (Method.POST.isSame(method)||Method.PUT.isSame(method)||Method.PATCH.isSame(method));
}
/**
* Validates the presence of the Content-Type header for an OPTIONS request.
*
* <p>
* According to the RFC specifications, an HTTP {@link Method#OPTIONS} request that contains content
* must have a Content-Type header. This method checks for the presence of the Content-Type header
* in such requests. It does not validate the actual value of the Content-Type header, as determining
* its validity would require knowledge of all valid media types, which is beyond the scope of this method.
* If the header is absent, a {@link ProtocolException} is thrown.
* </p>
*
* <p>
* Note: This method does not check the validity of the Content-Type header value, only its presence.
* </p>
*
* @param request The {@link HttpRequest} to be validated for the presence of the Content-Type header. Must not be null.
* @throws ProtocolException If the Content-Type header is missing in an OPTIONS request with content.
*/
public void validateOptionsContentType(final HttpRequest request) throws ProtocolException {
if (Method.OPTIONS.isSame(request.getMethod())) {
final Header header = request.getFirstHeader(HttpHeaders.CONTENT_TYPE);
if (header == null) {
throw new ProtocolException("OPTIONS request must have Content-Type header");
}
}
}
}