/*
* $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk/module-client/src/main/java/org/apache/http/impl/client/DefaultRedirectHandler.java $
* $Revision: 673450 $
* $Date: 2008-07-02 10:35:05 -0700 (Wed, 02 Jul 2008) $
*
* ====================================================================
* 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.http.impl.client;
import java.net.URI;
import java.net.URISyntaxException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.Header;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.ProtocolException;
import org.apache.http.client.CircularRedirectException;
import org.apache.http.client.RedirectHandler;
import org.apache.http.client.params.ClientPNames;
import org.apache.http.client.utils.URIUtils;
import org.apache.http.params.HttpParams;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.ExecutionContext;
/**
* Default implementation of {@link RedirectHandler}.
*
* @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
*
*
* <!-- empty lines to avoid svn diff problems -->
* @version $Revision: 673450 $
*
* @since 4.0
*/
public class DefaultRedirectHandler implements RedirectHandler {
private final Log log = LogFactory.getLog(getClass());
private static final String REDIRECT_LOCATIONS = "http.protocol.redirect-locations";
public DefaultRedirectHandler() {
super();
}
public boolean isRedirectRequested(
final HttpResponse response,
final HttpContext context) {
if (response == null) {
throw new IllegalArgumentException("HTTP response may not be null");
}
int statusCode = response.getStatusLine().getStatusCode();
switch (statusCode) {
case HttpStatus.SC_MOVED_TEMPORARILY:
case HttpStatus.SC_MOVED_PERMANENTLY:
case HttpStatus.SC_SEE_OTHER:
case HttpStatus.SC_TEMPORARY_REDIRECT:
return true;
default:
return false;
} //end of switch
}
public URI getLocationURI(
final HttpResponse response,
final HttpContext context) throws ProtocolException {
if (response == null) {
throw new IllegalArgumentException("HTTP response may not be null");
}
//get the location header to find out where to redirect to
Header locationHeader = response.getFirstHeader("location");
if (locationHeader == null) {
// got a redirect response, but no location header
throw new ProtocolException(
"Received redirect response " + response.getStatusLine()
+ " but no location header");
}
String location = locationHeader.getValue();
if (this.log.isDebugEnabled()) {
this.log.debug("Redirect requested to location '" + location + "'");
}
URI uri;
try {
uri = new URI(location);
} catch (URISyntaxException ex) {
throw new ProtocolException("Invalid redirect URI: " + location, ex);
}
HttpParams params = response.getParams();
// rfc2616 demands the location value be a complete URI
// Location = "Location" ":" absoluteURI
if (!uri.isAbsolute()) {
if (params.isParameterTrue(ClientPNames.REJECT_RELATIVE_REDIRECT)) {
throw new ProtocolException("Relative redirect location '"
+ uri + "' not allowed");
}
// Adjust location URI
HttpHost target = (HttpHost) context.getAttribute(
ExecutionContext.HTTP_TARGET_HOST);
if (target == null) {
throw new IllegalStateException("Target host not available " +
"in the HTTP context");
}
HttpRequest request = (HttpRequest) context.getAttribute(
ExecutionContext.HTTP_REQUEST);
try {
URI requestURI = new URI(request.getRequestLine().getUri());
URI absoluteRequestURI = URIUtils.rewriteURI(requestURI, target, true);
uri = URIUtils.resolve(absoluteRequestURI, uri);
} catch (URISyntaxException ex) {
throw new ProtocolException(ex.getMessage(), ex);
}
}
if (params.isParameterFalse(ClientPNames.ALLOW_CIRCULAR_REDIRECTS)) {
RedirectLocations redirectLocations = (RedirectLocations) context.getAttribute(
REDIRECT_LOCATIONS);
if (redirectLocations == null) {
redirectLocations = new RedirectLocations();
context.setAttribute(REDIRECT_LOCATIONS, redirectLocations);
}
URI redirectURI;
if (uri.getFragment() != null) {
try {
HttpHost target = new HttpHost(
uri.getHost(),
uri.getPort(),
uri.getScheme());
redirectURI = URIUtils.rewriteURI(uri, target, true);
} catch (URISyntaxException ex) {
throw new ProtocolException(ex.getMessage(), ex);
}
} else {
redirectURI = uri;
}
if (redirectLocations.contains(redirectURI)) {
throw new CircularRedirectException("Circular redirect to '" +
redirectURI + "'");
} else {
redirectLocations.add(redirectURI);
}
}
return uri;
}
}