/*
* ====================================================================
* 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.execchain;
import java.io.IOException;
import java.net.URI;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.HttpEntityEnclosingRequest;
import org.apache.http.HttpException;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.ProtocolException;
import org.apache.http.annotation.ThreadSafe;
import org.apache.http.auth.AuthScheme;
import org.apache.http.auth.AuthState;
import org.apache.http.client.RedirectException;
import org.apache.http.client.RedirectStrategy;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpExecutionAware;
import org.apache.http.client.methods.HttpRequestWrapper;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.client.utils.URIUtils;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.conn.routing.HttpRoutePlanner;
import org.apache.http.util.Args;
import org.apache.http.util.EntityUtils;
/**
* Request executor in the request execution chain that is responsible
* for handling of request redirects.
* <p/>
* Further responsibilities such as communication with the opposite
* endpoint is delegated to the next executor in the request execution
* chain.
*
* @since 4.3
*/
@ThreadSafe
public class RedirectExec implements ClientExecChain {
private final Log log = LogFactory.getLog(getClass());
private final ClientExecChain requestExecutor;
private final RedirectStrategy redirectStrategy;
private final HttpRoutePlanner routePlanner;
public RedirectExec(
final ClientExecChain requestExecutor,
final HttpRoutePlanner routePlanner,
final RedirectStrategy redirectStrategy) {
super();
Args.notNull(requestExecutor, "HTTP client request executor");
Args.notNull(routePlanner, "HTTP route planner");
Args.notNull(redirectStrategy, "HTTP redirect strategy");
this.requestExecutor = requestExecutor;
this.routePlanner = routePlanner;
this.redirectStrategy = redirectStrategy;
}
public CloseableHttpResponse execute(
final HttpRoute route,
final HttpRequestWrapper request,
final HttpClientContext context,
final HttpExecutionAware execAware) throws IOException, HttpException {
Args.notNull(route, "HTTP route");
Args.notNull(request, "HTTP request");
Args.notNull(context, "HTTP context");
final List<URI> redirectLocations = context.getRedirectLocations();
if (redirectLocations != null) {
redirectLocations.clear();
}
final RequestConfig config = context.getRequestConfig();
final int maxRedirects = config.getMaxRedirects() > 0 ? config.getMaxRedirects() : 50;
HttpRoute currentRoute = route;
HttpRequestWrapper currentRequest = request;
for (int redirectCount = 0;;) {
final CloseableHttpResponse response = requestExecutor.execute(
currentRoute, currentRequest, context, execAware);
try {
if (config.isRedirectsEnabled() &&
this.redirectStrategy.isRedirected(currentRequest, response, context)) {
if (redirectCount >= maxRedirects) {
throw new RedirectException("Maximum redirects ("+ maxRedirects + ") exceeded");
}
redirectCount++;
final HttpRequest redirect = this.redirectStrategy.getRedirect(
currentRequest, response, context);
if (!redirect.headerIterator().hasNext()) {
final HttpRequest original = request.getOriginal();
redirect.setHeaders(original.getAllHeaders());
}
currentRequest = HttpRequestWrapper.wrap(redirect);
if (currentRequest instanceof HttpEntityEnclosingRequest) {
Proxies.enhanceEntity((HttpEntityEnclosingRequest) currentRequest);
}
final URI uri = currentRequest.getURI();
final HttpHost newTarget = URIUtils.extractHost(uri);
if (newTarget == null) {
throw new ProtocolException("Redirect URI does not specify a valid host name: " +
uri);
}
// Reset virtual host and auth states if redirecting to another host
if (!currentRoute.getTargetHost().equals(newTarget)) {
final AuthState targetAuthState = context.getTargetAuthState();
if (targetAuthState != null) {
this.log.debug("Resetting target auth state");
targetAuthState.reset();
}
final AuthState proxyAuthState = context.getProxyAuthState();
if (proxyAuthState != null) {
final AuthScheme authScheme = proxyAuthState.getAuthScheme();
if (authScheme != null && authScheme.isConnectionBased()) {
this.log.debug("Resetting proxy auth state");
proxyAuthState.reset();
}
}
}
currentRoute = this.routePlanner.determineRoute(newTarget, currentRequest, context);
if (this.log.isDebugEnabled()) {
this.log.debug("Redirecting to '" + uri + "' via " + currentRoute);
}
EntityUtils.consume(response.getEntity());
response.close();
} else {
return response;
}
} catch (final RuntimeException ex) {
response.close();
throw ex;
} catch (final IOException ex) {
response.close();
throw ex;
} catch (final HttpException ex) {
// Protocol exception related to a direct.
// The underlying connection may still be salvaged.
try {
EntityUtils.consume(response.getEntity());
} catch (final IOException ioex) {
this.log.debug("I/O error while releasing connection", ioex);
} finally {
response.close();
}
throw ex;
}
}
}
}