1
27
28 package org.apache.http.impl.execchain;
29
30 import java.io.IOException;
31 import java.net.URI;
32 import java.util.List;
33
34 import org.apache.commons.logging.Log;
35 import org.apache.commons.logging.LogFactory;
36 import org.apache.http.HttpEntityEnclosingRequest;
37 import org.apache.http.HttpException;
38 import org.apache.http.HttpHost;
39 import org.apache.http.HttpRequest;
40 import org.apache.http.ProtocolException;
41 import org.apache.http.annotation.Contract;
42 import org.apache.http.annotation.ThreadingBehavior;
43 import org.apache.http.auth.AuthState;
44 import org.apache.http.client.RedirectException;
45 import org.apache.http.client.RedirectStrategy;
46 import org.apache.http.client.config.RequestConfig;
47 import org.apache.http.client.methods.CloseableHttpResponse;
48 import org.apache.http.client.methods.HttpExecutionAware;
49 import org.apache.http.client.methods.HttpRequestWrapper;
50 import org.apache.http.client.protocol.HttpClientContext;
51 import org.apache.http.client.utils.URIUtils;
52 import org.apache.http.conn.routing.HttpRoute;
53 import org.apache.http.conn.routing.HttpRoutePlanner;
54 import org.apache.http.util.Args;
55 import org.apache.http.util.EntityUtils;
56
57
68 @Contract(threading = ThreadingBehavior.IMMUTABLE_CONDITIONAL)
69 public class RedirectExec implements ClientExecChain {
70
71 private final Log log = LogFactory.getLog(getClass());
72
73 private final ClientExecChain requestExecutor;
74 private final RedirectStrategy redirectStrategy;
75 private final HttpRoutePlanner routePlanner;
76
77 public RedirectExec(
78 final ClientExecChain requestExecutor,
79 final HttpRoutePlanner routePlanner,
80 final RedirectStrategy redirectStrategy) {
81 super();
82 Args.notNull(requestExecutor, "HTTP client request executor");
83 Args.notNull(routePlanner, "HTTP route planner");
84 Args.notNull(redirectStrategy, "HTTP redirect strategy");
85 this.requestExecutor = requestExecutor;
86 this.routePlanner = routePlanner;
87 this.redirectStrategy = redirectStrategy;
88 }
89
90 @Override
91 public CloseableHttpResponse execute(
92 final HttpRoute route,
93 final HttpRequestWrapper request,
94 final HttpClientContext context,
95 final HttpExecutionAware execAware) throws IOException, HttpException {
96 Args.notNull(route, "HTTP route");
97 Args.notNull(request, "HTTP request");
98 Args.notNull(context, "HTTP context");
99
100 final List<URI> redirectLocations = context.getRedirectLocations();
101 if (redirectLocations != null) {
102 redirectLocations.clear();
103 }
104
105 final RequestConfig config = context.getRequestConfig();
106 final int maxRedirects = config.getMaxRedirects() > 0 ? config.getMaxRedirects() : 50;
107 HttpRoute currentRoute = route;
108 HttpRequestWrapper currentRequest = request;
109 for (int redirectCount = 0;;) {
110 final CloseableHttpResponse response = requestExecutor.execute(
111 currentRoute, currentRequest, context, execAware);
112 try {
113 if (config.isRedirectsEnabled() &&
114 this.redirectStrategy.isRedirected(currentRequest.getOriginal(), response, context)) {
115 if (!RequestEntityProxy.isRepeatable(currentRequest)) {
116 if (log.isDebugEnabled()) {
117 log.debug("Cannot redirect non-repeatable request");
118 }
119 return response;
120 }
121 if (redirectCount >= maxRedirects) {
122 throw new RedirectException("Maximum redirects ("+ maxRedirects + ") exceeded");
123 }
124 redirectCount++;
125
126 final HttpRequest redirect = this.redirectStrategy.getRedirect(
127 currentRequest.getOriginal(), response, context);
128 if (!redirect.headerIterator().hasNext()) {
129 final HttpRequest original = request.getOriginal();
130 redirect.setHeaders(original.getAllHeaders());
131 }
132 currentRequest = HttpRequestWrapper.wrap(redirect);
133
134 if (currentRequest instanceof HttpEntityEnclosingRequest) {
135 RequestEntityProxy.enhance((HttpEntityEnclosingRequest) currentRequest);
136 }
137
138 final URI uri = currentRequest.getURI();
139 final HttpHost newTarget = URIUtils.extractHost(uri);
140 if (newTarget == null) {
141 throw new ProtocolException("Redirect URI does not specify a valid host name: " +
142 uri);
143 }
144
145
146 if (!currentRoute.getTargetHost().equals(newTarget)) {
147 final AuthState targetAuthState = context.getTargetAuthState();
148 if (targetAuthState != null) {
149 this.log.debug("Resetting target auth state");
150 targetAuthState.reset();
151 }
152 final AuthState proxyAuthState = context.getProxyAuthState();
153 if (proxyAuthState != null && proxyAuthState.isConnectionBased()) {
154 this.log.debug("Resetting proxy auth state");
155 proxyAuthState.reset();
156 }
157 }
158
159 currentRoute = this.routePlanner.determineRoute(newTarget, currentRequest, context);
160 if (this.log.isDebugEnabled()) {
161 this.log.debug("Redirecting to '" + uri + "' via " + currentRoute);
162 }
163 EntityUtils.consume(response.getEntity());
164 response.close();
165 } else {
166 return response;
167 }
168 } catch (final RuntimeException ex) {
169 response.close();
170 throw ex;
171 } catch (final IOException ex) {
172 response.close();
173 throw ex;
174 } catch (final HttpException ex) {
175
176
177 try {
178 EntityUtils.consume(response.getEntity());
179 } catch (final IOException ioex) {
180 this.log.debug("I/O error while releasing connection", ioex);
181 } finally {
182 response.close();
183 }
184 throw ex;
185 }
186 }
187 }
188
189 }
190