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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.eclipse.aether.transport.apache;
20  
21  import java.io.File;
22  import java.io.IOException;
23  import java.io.InputStream;
24  import java.io.InterruptedIOException;
25  import java.io.OutputStream;
26  import java.io.UncheckedIOException;
27  import java.net.InetAddress;
28  import java.net.URI;
29  import java.net.URISyntaxException;
30  import java.net.UnknownHostException;
31  import java.nio.charset.Charset;
32  import java.nio.file.Files;
33  import java.nio.file.StandardCopyOption;
34  import java.nio.file.attribute.FileTime;
35  import java.util.Collections;
36  import java.util.Date;
37  import java.util.HashMap;
38  import java.util.HashSet;
39  import java.util.List;
40  import java.util.Map;
41  import java.util.Set;
42  import java.util.regex.Matcher;
43  import java.util.regex.Pattern;
44  
45  import org.apache.http.Header;
46  import org.apache.http.HttpEntity;
47  import org.apache.http.HttpEntityEnclosingRequest;
48  import org.apache.http.HttpHeaders;
49  import org.apache.http.HttpHost;
50  import org.apache.http.HttpResponse;
51  import org.apache.http.HttpStatus;
52  import org.apache.http.auth.AuthSchemeProvider;
53  import org.apache.http.auth.AuthScope;
54  import org.apache.http.client.CredentialsProvider;
55  import org.apache.http.client.HttpRequestRetryHandler;
56  import org.apache.http.client.HttpResponseException;
57  import org.apache.http.client.ServiceUnavailableRetryStrategy;
58  import org.apache.http.client.config.AuthSchemes;
59  import org.apache.http.client.config.RequestConfig;
60  import org.apache.http.client.methods.CloseableHttpResponse;
61  import org.apache.http.client.methods.HttpGet;
62  import org.apache.http.client.methods.HttpHead;
63  import org.apache.http.client.methods.HttpOptions;
64  import org.apache.http.client.methods.HttpPut;
65  import org.apache.http.client.methods.HttpUriRequest;
66  import org.apache.http.client.utils.DateUtils;
67  import org.apache.http.client.utils.URIUtils;
68  import org.apache.http.config.Registry;
69  import org.apache.http.config.RegistryBuilder;
70  import org.apache.http.config.SocketConfig;
71  import org.apache.http.entity.AbstractHttpEntity;
72  import org.apache.http.entity.ByteArrayEntity;
73  import org.apache.http.impl.NoConnectionReuseStrategy;
74  import org.apache.http.impl.auth.BasicScheme;
75  import org.apache.http.impl.auth.BasicSchemeFactory;
76  import org.apache.http.impl.auth.DigestSchemeFactory;
77  import org.apache.http.impl.auth.KerberosSchemeFactory;
78  import org.apache.http.impl.auth.NTLMSchemeFactory;
79  import org.apache.http.impl.auth.SPNegoSchemeFactory;
80  import org.apache.http.impl.client.CloseableHttpClient;
81  import org.apache.http.impl.client.DefaultHttpRequestRetryHandler;
82  import org.apache.http.impl.client.HttpClientBuilder;
83  import org.apache.http.impl.client.StandardHttpRequestRetryHandler;
84  import org.apache.http.protocol.HttpContext;
85  import org.apache.http.util.EntityUtils;
86  import org.eclipse.aether.ConfigurationProperties;
87  import org.eclipse.aether.RepositorySystemSession;
88  import org.eclipse.aether.repository.AuthenticationContext;
89  import org.eclipse.aether.repository.Proxy;
90  import org.eclipse.aether.repository.RemoteRepository;
91  import org.eclipse.aether.spi.connector.transport.AbstractTransporter;
92  import org.eclipse.aether.spi.connector.transport.GetTask;
93  import org.eclipse.aether.spi.connector.transport.PeekTask;
94  import org.eclipse.aether.spi.connector.transport.PutTask;
95  import org.eclipse.aether.spi.connector.transport.TransportTask;
96  import org.eclipse.aether.spi.connector.transport.http.HttpTransporter;
97  import org.eclipse.aether.spi.connector.transport.http.HttpTransporterException;
98  import org.eclipse.aether.transfer.NoTransporterException;
99  import org.eclipse.aether.transfer.TransferCancelledException;
100 import org.eclipse.aether.util.ConfigUtils;
101 import org.eclipse.aether.util.FileUtils;
102 import org.slf4j.Logger;
103 import org.slf4j.LoggerFactory;
104 
105 import static java.util.Objects.requireNonNull;
106 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.CONFIG_PROP_HTTP_RETRY_HANDLER_NAME;
107 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.CONFIG_PROP_HTTP_RETRY_HANDLER_REQUEST_SENT_ENABLED;
108 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.CONFIG_PROP_USE_SYSTEM_PROPERTIES;
109 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.DEFAULT_HTTP_RETRY_HANDLER_REQUEST_SENT_ENABLED;
110 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.DEFAULT_USE_SYSTEM_PROPERTIES;
111 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.HTTP_RETRY_HANDLER_NAME_DEFAULT;
112 import static org.eclipse.aether.transport.apache.ApacheTransporterConfigurationKeys.HTTP_RETRY_HANDLER_NAME_STANDARD;
113 
114 /**
115  * A transporter for HTTP/HTTPS.
116  */
117 final class ApacheTransporter extends AbstractTransporter implements HttpTransporter {
118     private static final Pattern CONTENT_RANGE_PATTERN =
119             Pattern.compile("\\s*bytes\\s+([0-9]+)\\s*-\\s*([0-9]+)\\s*/.*");
120 
121     private static final Logger LOGGER = LoggerFactory.getLogger(ApacheTransporter.class);
122 
123     private final AuthenticationContext repoAuthContext;
124 
125     private final AuthenticationContext proxyAuthContext;
126 
127     private final URI baseUri;
128 
129     private final HttpHost server;
130 
131     private final HttpHost proxy;
132 
133     private final CloseableHttpClient client;
134 
135     private final Map<?, ?> headers;
136 
137     private final LocalState state;
138 
139     private final boolean preemptiveAuth;
140 
141     private final boolean preemptivePutAuth;
142 
143     private final boolean supportWebDav;
144 
145     @SuppressWarnings("checkstyle:methodlength")
146     ApacheTransporter(RemoteRepository repository, RepositorySystemSession session) throws NoTransporterException {
147         if (!"http".equalsIgnoreCase(repository.getProtocol()) && !"https".equalsIgnoreCase(repository.getProtocol())) {
148             throw new NoTransporterException(repository);
149         }
150         try {
151             this.baseUri = new URI(repository.getUrl()).parseServerAuthority();
152             if (baseUri.isOpaque()) {
153                 throw new URISyntaxException(repository.getUrl(), "URL must not be opaque");
154             }
155             this.server = URIUtils.extractHost(baseUri);
156             if (server == null) {
157                 throw new URISyntaxException(repository.getUrl(), "URL lacks host name");
158             }
159         } catch (URISyntaxException e) {
160             throw new NoTransporterException(repository, e.getMessage(), e);
161         }
162         this.proxy = toHost(repository.getProxy());
163 
164         this.repoAuthContext = AuthenticationContext.forRepository(session, repository);
165         this.proxyAuthContext = AuthenticationContext.forProxy(session, repository);
166 
167         String httpsSecurityMode = ConfigUtils.getString(
168                 session,
169                 ConfigurationProperties.HTTPS_SECURITY_MODE_DEFAULT,
170                 ConfigurationProperties.HTTPS_SECURITY_MODE + "." + repository.getId(),
171                 ConfigurationProperties.HTTPS_SECURITY_MODE);
172         final int connectionMaxTtlSeconds = ConfigUtils.getInteger(
173                 session,
174                 ConfigurationProperties.DEFAULT_HTTP_CONNECTION_MAX_TTL,
175                 ConfigurationProperties.HTTP_CONNECTION_MAX_TTL + "." + repository.getId(),
176                 ConfigurationProperties.HTTP_CONNECTION_MAX_TTL);
177         final int maxConnectionsPerRoute = ConfigUtils.getInteger(
178                 session,
179                 ConfigurationProperties.DEFAULT_HTTP_MAX_CONNECTIONS_PER_ROUTE,
180                 ConfigurationProperties.HTTP_MAX_CONNECTIONS_PER_ROUTE + "." + repository.getId(),
181                 ConfigurationProperties.HTTP_MAX_CONNECTIONS_PER_ROUTE);
182         this.state = new LocalState(
183                 session,
184                 repository,
185                 new ConnMgrConfig(
186                         session, repoAuthContext, httpsSecurityMode, connectionMaxTtlSeconds, maxConnectionsPerRoute));
187 
188         this.headers = ConfigUtils.getMap(
189                 session,
190                 Collections.emptyMap(),
191                 ConfigurationProperties.HTTP_HEADERS + "." + repository.getId(),
192                 ConfigurationProperties.HTTP_HEADERS);
193 
194         this.preemptiveAuth = ConfigUtils.getBoolean(
195                 session,
196                 ConfigurationProperties.DEFAULT_HTTP_PREEMPTIVE_AUTH,
197                 ConfigurationProperties.HTTP_PREEMPTIVE_AUTH + "." + repository.getId(),
198                 ConfigurationProperties.HTTP_PREEMPTIVE_AUTH);
199         this.preemptivePutAuth = ConfigUtils.getBoolean(
200                 session,
201                 ConfigurationProperties.DEFAULT_HTTP_PREEMPTIVE_PUT_AUTH,
202                 ConfigurationProperties.HTTP_PREEMPTIVE_PUT_AUTH + "." + repository.getId(),
203                 ConfigurationProperties.HTTP_PREEMPTIVE_PUT_AUTH);
204         this.supportWebDav = ConfigUtils.getBoolean(
205                 session,
206                 ConfigurationProperties.DEFAULT_HTTP_SUPPORT_WEBDAV,
207                 ConfigurationProperties.HTTP_SUPPORT_WEBDAV + "." + repository.getId(),
208                 ConfigurationProperties.HTTP_SUPPORT_WEBDAV);
209         String credentialEncoding = ConfigUtils.getString(
210                 session,
211                 ConfigurationProperties.DEFAULT_HTTP_CREDENTIAL_ENCODING,
212                 ConfigurationProperties.HTTP_CREDENTIAL_ENCODING + "." + repository.getId(),
213                 ConfigurationProperties.HTTP_CREDENTIAL_ENCODING);
214         int connectTimeout = ConfigUtils.getInteger(
215                 session,
216                 ConfigurationProperties.DEFAULT_CONNECT_TIMEOUT,
217                 ConfigurationProperties.CONNECT_TIMEOUT + "." + repository.getId(),
218                 ConfigurationProperties.CONNECT_TIMEOUT);
219         int requestTimeout = ConfigUtils.getInteger(
220                 session,
221                 ConfigurationProperties.DEFAULT_REQUEST_TIMEOUT,
222                 ConfigurationProperties.REQUEST_TIMEOUT + "." + repository.getId(),
223                 ConfigurationProperties.REQUEST_TIMEOUT);
224         int retryCount = ConfigUtils.getInteger(
225                 session,
226                 ConfigurationProperties.DEFAULT_HTTP_RETRY_HANDLER_COUNT,
227                 ConfigurationProperties.HTTP_RETRY_HANDLER_COUNT + "." + repository.getId(),
228                 ConfigurationProperties.HTTP_RETRY_HANDLER_COUNT);
229         long retryInterval = ConfigUtils.getLong(
230                 session,
231                 ConfigurationProperties.DEFAULT_HTTP_RETRY_HANDLER_INTERVAL,
232                 ConfigurationProperties.HTTP_RETRY_HANDLER_INTERVAL + "." + repository.getId(),
233                 ConfigurationProperties.HTTP_RETRY_HANDLER_INTERVAL);
234         long retryIntervalMax = ConfigUtils.getLong(
235                 session,
236                 ConfigurationProperties.DEFAULT_HTTP_RETRY_HANDLER_INTERVAL_MAX,
237                 ConfigurationProperties.HTTP_RETRY_HANDLER_INTERVAL_MAX + "." + repository.getId(),
238                 ConfigurationProperties.HTTP_RETRY_HANDLER_INTERVAL_MAX);
239         String serviceUnavailableCodesString = ConfigUtils.getString(
240                 session,
241                 ConfigurationProperties.DEFAULT_HTTP_RETRY_HANDLER_SERVICE_UNAVAILABLE,
242                 ConfigurationProperties.HTTP_RETRY_HANDLER_SERVICE_UNAVAILABLE + "." + repository.getId(),
243                 ConfigurationProperties.HTTP_RETRY_HANDLER_SERVICE_UNAVAILABLE);
244         String retryHandlerName = ConfigUtils.getString(
245                 session,
246                 HTTP_RETRY_HANDLER_NAME_STANDARD,
247                 CONFIG_PROP_HTTP_RETRY_HANDLER_NAME + "." + repository.getId(),
248                 CONFIG_PROP_HTTP_RETRY_HANDLER_NAME);
249         boolean retryHandlerRequestSentEnabled = ConfigUtils.getBoolean(
250                 session,
251                 DEFAULT_HTTP_RETRY_HANDLER_REQUEST_SENT_ENABLED,
252                 CONFIG_PROP_HTTP_RETRY_HANDLER_REQUEST_SENT_ENABLED + "." + repository.getId(),
253                 CONFIG_PROP_HTTP_RETRY_HANDLER_REQUEST_SENT_ENABLED);
254         String userAgent = ConfigUtils.getString(
255                 session, ConfigurationProperties.DEFAULT_USER_AGENT, ConfigurationProperties.USER_AGENT);
256 
257         Charset credentialsCharset = Charset.forName(credentialEncoding);
258         Registry<AuthSchemeProvider> authSchemeRegistry = RegistryBuilder.<AuthSchemeProvider>create()
259                 .register(AuthSchemes.BASIC, new BasicSchemeFactory(credentialsCharset))
260                 .register(AuthSchemes.DIGEST, new DigestSchemeFactory(credentialsCharset))
261                 .register(AuthSchemes.NTLM, new NTLMSchemeFactory())
262                 .register(AuthSchemes.SPNEGO, new SPNegoSchemeFactory())
263                 .register(AuthSchemes.KERBEROS, new KerberosSchemeFactory())
264                 .build();
265         SocketConfig socketConfig =
266                 SocketConfig.custom().setSoTimeout(requestTimeout).build();
267         RequestConfig requestConfig = RequestConfig.custom()
268                 .setConnectTimeout(connectTimeout)
269                 .setConnectionRequestTimeout(connectTimeout)
270                 .setLocalAddress(getHttpLocalAddress(session, repository))
271                 .setSocketTimeout(requestTimeout)
272                 .build();
273 
274         HttpRequestRetryHandler retryHandler;
275         if (HTTP_RETRY_HANDLER_NAME_STANDARD.equals(retryHandlerName)) {
276             retryHandler = new StandardHttpRequestRetryHandler(retryCount, retryHandlerRequestSentEnabled);
277         } else if (HTTP_RETRY_HANDLER_NAME_DEFAULT.equals(retryHandlerName)) {
278             retryHandler = new DefaultHttpRequestRetryHandler(retryCount, retryHandlerRequestSentEnabled);
279         } else {
280             throw new IllegalArgumentException(
281                     "Unsupported parameter " + CONFIG_PROP_HTTP_RETRY_HANDLER_NAME + " value: " + retryHandlerName);
282         }
283         Set<Integer> serviceUnavailableCodes = new HashSet<>();
284         try {
285             for (String code : ConfigUtils.parseCommaSeparatedUniqueNames(serviceUnavailableCodesString)) {
286                 serviceUnavailableCodes.add(Integer.parseInt(code));
287             }
288         } catch (NumberFormatException e) {
289             throw new IllegalArgumentException(
290                     "Illegal HTTP codes for " + ConfigurationProperties.HTTP_RETRY_HANDLER_SERVICE_UNAVAILABLE
291                             + " (list of integers): " + serviceUnavailableCodesString);
292         }
293         ServiceUnavailableRetryStrategy serviceUnavailableRetryStrategy = new ResolverServiceUnavailableRetryStrategy(
294                 retryCount, retryInterval, retryIntervalMax, serviceUnavailableCodes);
295 
296         HttpClientBuilder builder = HttpClientBuilder.create()
297                 .setUserAgent(userAgent)
298                 .setDefaultSocketConfig(socketConfig)
299                 .setDefaultRequestConfig(requestConfig)
300                 .setServiceUnavailableRetryStrategy(serviceUnavailableRetryStrategy)
301                 .setRetryHandler(retryHandler)
302                 .setDefaultAuthSchemeRegistry(authSchemeRegistry)
303                 .setConnectionManager(state.getConnectionManager())
304                 .setConnectionManagerShared(true)
305                 .setDefaultCredentialsProvider(toCredentialsProvider(server, repoAuthContext, proxy, proxyAuthContext))
306                 .setProxy(proxy);
307         final boolean useSystemProperties = ConfigUtils.getBoolean(
308                 session,
309                 DEFAULT_USE_SYSTEM_PROPERTIES,
310                 CONFIG_PROP_USE_SYSTEM_PROPERTIES + "." + repository.getId(),
311                 CONFIG_PROP_USE_SYSTEM_PROPERTIES);
312         if (useSystemProperties) {
313             LOGGER.warn(
314                     "Transport used Apache HttpClient is instructed to use system properties: this may yield in unwanted side-effects!");
315             LOGGER.warn("Please use documented means to configure resolver transport.");
316             builder.useSystemProperties();
317         }
318 
319         final String expectContinue = ConfigUtils.getString(
320                 session,
321                 null,
322                 ConfigurationProperties.HTTP_EXPECT_CONTINUE + "." + repository.getId(),
323                 ConfigurationProperties.HTTP_EXPECT_CONTINUE);
324         if (expectContinue != null) {
325             state.setExpectContinue(Boolean.parseBoolean(expectContinue));
326         }
327 
328         final boolean reuseConnections = ConfigUtils.getBoolean(
329                 session,
330                 ConfigurationProperties.DEFAULT_HTTP_REUSE_CONNECTIONS,
331                 ConfigurationProperties.HTTP_REUSE_CONNECTIONS + "." + repository.getId(),
332                 ConfigurationProperties.HTTP_REUSE_CONNECTIONS);
333         if (!reuseConnections) {
334             builder.setConnectionReuseStrategy(NoConnectionReuseStrategy.INSTANCE);
335         }
336 
337         this.client = builder.build();
338     }
339 
340     /**
341      * Returns non-null {@link InetAddress} if set in configuration, {@code null} otherwise.
342      */
343     private InetAddress getHttpLocalAddress(RepositorySystemSession session, RemoteRepository repository) {
344         String bindAddress = ConfigUtils.getString(
345                 session,
346                 null,
347                 ConfigurationProperties.HTTP_LOCAL_ADDRESS + "." + repository.getId(),
348                 ConfigurationProperties.HTTP_LOCAL_ADDRESS);
349         if (bindAddress == null) {
350             return null;
351         }
352         try {
353             return InetAddress.getByName(bindAddress);
354         } catch (UnknownHostException uhe) {
355             throw new IllegalArgumentException(
356                     "Given bind address (" + bindAddress + ") cannot be resolved for remote repository " + repository,
357                     uhe);
358         }
359     }
360 
361     private static HttpHost toHost(Proxy proxy) {
362         HttpHost host = null;
363         if (proxy != null) {
364             host = new HttpHost(proxy.getHost(), proxy.getPort());
365         }
366         return host;
367     }
368 
369     private static CredentialsProvider toCredentialsProvider(
370             HttpHost server, AuthenticationContext serverAuthCtx, HttpHost proxy, AuthenticationContext proxyAuthCtx) {
371         CredentialsProvider provider = toCredentialsProvider(server.getHostName(), AuthScope.ANY_PORT, serverAuthCtx);
372         if (proxy != null) {
373             CredentialsProvider p = toCredentialsProvider(proxy.getHostName(), proxy.getPort(), proxyAuthCtx);
374             provider = new DemuxCredentialsProvider(provider, p, proxy);
375         }
376         return provider;
377     }
378 
379     private static CredentialsProvider toCredentialsProvider(String host, int port, AuthenticationContext ctx) {
380         DeferredCredentialsProvider provider = new DeferredCredentialsProvider();
381         if (ctx != null) {
382             AuthScope basicScope = new AuthScope(host, port);
383             provider.setCredentials(basicScope, new DeferredCredentialsProvider.BasicFactory(ctx));
384 
385             AuthScope ntlmScope = new AuthScope(host, port, AuthScope.ANY_REALM, "ntlm");
386             provider.setCredentials(ntlmScope, new DeferredCredentialsProvider.NtlmFactory(ctx));
387         }
388         return provider;
389     }
390 
391     LocalState getState() {
392         return state;
393     }
394 
395     private URI resolve(TransportTask task) {
396         return UriUtils.resolve(baseUri, task.getLocation());
397     }
398 
399     @Override
400     public int classify(Throwable error) {
401         if (error instanceof HttpTransporterException
402                 && ((HttpTransporterException) error).getStatusCode() == HttpStatus.SC_NOT_FOUND) {
403             return ERROR_NOT_FOUND;
404         }
405         return ERROR_OTHER;
406     }
407 
408     @Override
409     protected void implPeek(PeekTask task) throws Exception {
410         HttpHead request = commonHeaders(new HttpHead(resolve(task)));
411         try {
412             execute(request, null);
413         } catch (HttpResponseException e) {
414             throw new HttpTransporterException(e.getStatusCode());
415         }
416     }
417 
418     @Override
419     protected void implGet(GetTask task) throws Exception {
420         boolean resume = true;
421 
422         EntityGetter getter = new EntityGetter(task);
423         HttpGet request = commonHeaders(new HttpGet(resolve(task)));
424         while (true) {
425             try {
426                 if (resume) {
427                     resume(request, task);
428                 }
429                 execute(request, getter);
430                 break;
431             } catch (HttpResponseException e) {
432                 if (resume
433                         && e.getStatusCode() == HttpStatus.SC_PRECONDITION_FAILED
434                         && request.containsHeader(HttpHeaders.RANGE)) {
435                     request = commonHeaders(new HttpGet(resolve(task)));
436                     resume = false;
437                     continue;
438                 }
439                 throw new HttpTransporterException(e.getStatusCode());
440             }
441         }
442     }
443 
444     @Override
445     protected void implPut(PutTask task) throws Exception {
446         PutTaskEntity entity = new PutTaskEntity(task);
447         HttpPut request = commonHeaders(entity(new HttpPut(resolve(task)), entity));
448         try {
449             execute(request, null);
450         } catch (HttpResponseException e) {
451             if (e.getStatusCode() == HttpStatus.SC_EXPECTATION_FAILED && request.containsHeader(HttpHeaders.EXPECT)) {
452                 state.setExpectContinue(false);
453                 request = commonHeaders(entity(new HttpPut(request.getURI()), entity));
454                 execute(request, null);
455                 return;
456             }
457             throw new HttpTransporterException(e.getStatusCode());
458         }
459     }
460 
461     private void execute(HttpUriRequest request, EntityGetter getter) throws Exception {
462         try {
463             SharingHttpContext context = new SharingHttpContext(state);
464             prepare(request, context);
465             try (CloseableHttpResponse response = client.execute(server, request, context)) {
466                 try {
467                     context.close();
468                     handleStatus(response);
469                     if (getter != null) {
470                         getter.handle(response);
471                     }
472                 } finally {
473                     EntityUtils.consumeQuietly(response.getEntity());
474                 }
475             }
476         } catch (IOException e) {
477             if (e.getCause() instanceof TransferCancelledException) {
478                 throw (Exception) e.getCause();
479             }
480             throw e;
481         }
482     }
483 
484     private void prepare(HttpUriRequest request, SharingHttpContext context) throws HttpTransporterException {
485         final boolean put = HttpPut.METHOD_NAME.equalsIgnoreCase(request.getMethod());
486         if (preemptiveAuth || (preemptivePutAuth && put)) {
487             context.getAuthCache().put(server, new BasicScheme());
488         }
489         if (supportWebDav) {
490             if (state.getWebDav() == null && (put || isPayloadPresent(request))) {
491                 HttpOptions req = commonHeaders(new HttpOptions(request.getURI()));
492                 try (CloseableHttpResponse response = client.execute(server, req, context)) {
493                     state.setWebDav(response.containsHeader(HttpHeaders.DAV));
494                     EntityUtils.consumeQuietly(response.getEntity());
495                 } catch (IOException e) {
496                     LOGGER.debug("Failed to prepare HTTP context", e);
497                 }
498             }
499             if (put && Boolean.TRUE.equals(state.getWebDav())) {
500                 mkdirs(request.getURI(), context);
501             }
502         }
503     }
504 
505     @SuppressWarnings("checkstyle:magicnumber")
506     private void mkdirs(URI uri, SharingHttpContext context) throws HttpTransporterException {
507         List<URI> dirs = UriUtils.getDirectories(baseUri, uri);
508         int index = 0;
509         for (; index < dirs.size(); index++) {
510             try (CloseableHttpResponse response =
511                     client.execute(server, commonHeaders(new HttpMkCol(dirs.get(index))), context)) {
512                 try {
513                     int status = response.getStatusLine().getStatusCode();
514                     if (status < 300 || status == HttpStatus.SC_METHOD_NOT_ALLOWED) {
515                         break;
516                     } else if (status == HttpStatus.SC_CONFLICT) {
517                         continue;
518                     }
519                     handleStatus(response);
520                 } finally {
521                     EntityUtils.consumeQuietly(response.getEntity());
522                 }
523             } catch (IOException e) {
524                 LOGGER.debug("Failed to create parent directory {}", dirs.get(index), e);
525                 return;
526             }
527         }
528         for (index--; index >= 0; index--) {
529             try (CloseableHttpResponse response =
530                     client.execute(server, commonHeaders(new HttpMkCol(dirs.get(index))), context)) {
531                 try {
532                     handleStatus(response);
533                 } finally {
534                     EntityUtils.consumeQuietly(response.getEntity());
535                 }
536             } catch (IOException e) {
537                 LOGGER.debug("Failed to create parent directory {}", dirs.get(index), e);
538                 return;
539             }
540         }
541     }
542 
543     private <T extends HttpEntityEnclosingRequest> T entity(T request, HttpEntity entity) {
544         request.setEntity(entity);
545         return request;
546     }
547 
548     private boolean isPayloadPresent(HttpUriRequest request) {
549         if (request instanceof HttpEntityEnclosingRequest) {
550             HttpEntity entity = ((HttpEntityEnclosingRequest) request).getEntity();
551             return entity != null && entity.getContentLength() != 0;
552         }
553         return false;
554     }
555 
556     private <T extends HttpUriRequest> T commonHeaders(T request) {
557         request.setHeader(HttpHeaders.CACHE_CONTROL, "no-cache, no-store");
558         request.setHeader(HttpHeaders.PRAGMA, "no-cache");
559 
560         if (state.isExpectContinue() && isPayloadPresent(request)) {
561             request.setHeader(HttpHeaders.EXPECT, "100-continue");
562         }
563 
564         for (Map.Entry<?, ?> entry : headers.entrySet()) {
565             if (!(entry.getKey() instanceof String)) {
566                 continue;
567             }
568             if (entry.getValue() instanceof String) {
569                 request.setHeader(entry.getKey().toString(), entry.getValue().toString());
570             } else {
571                 request.removeHeaders(entry.getKey().toString());
572             }
573         }
574 
575         if (!state.isExpectContinue()) {
576             request.removeHeaders(HttpHeaders.EXPECT);
577         }
578 
579         return request;
580     }
581 
582     @SuppressWarnings("checkstyle:magicnumber")
583     private <T extends HttpUriRequest> void resume(T request, GetTask task) {
584         long resumeOffset = task.getResumeOffset();
585         if (resumeOffset > 0L && task.getDataFile() != null) {
586             request.setHeader(HttpHeaders.RANGE, "bytes=" + resumeOffset + '-');
587             request.setHeader(
588                     HttpHeaders.IF_UNMODIFIED_SINCE,
589                     DateUtils.formatDate(new Date(task.getDataFile().lastModified() - 60L * 1000L)));
590             request.setHeader(HttpHeaders.ACCEPT_ENCODING, "identity");
591         }
592     }
593 
594     @SuppressWarnings("checkstyle:magicnumber")
595     private void handleStatus(CloseableHttpResponse response) throws HttpResponseException {
596         int status = response.getStatusLine().getStatusCode();
597         if (status >= 300) {
598             throw new HttpResponseException(status, response.getStatusLine().getReasonPhrase() + " (" + status + ")");
599         }
600     }
601 
602     @Override
603     protected void implClose() {
604         try {
605             client.close();
606         } catch (IOException e) {
607             throw new UncheckedIOException(e);
608         }
609         AuthenticationContext.close(repoAuthContext);
610         AuthenticationContext.close(proxyAuthContext);
611         state.close();
612     }
613 
614     private class EntityGetter {
615 
616         private final GetTask task;
617 
618         EntityGetter(GetTask task) {
619             this.task = task;
620         }
621 
622         public void handle(CloseableHttpResponse response) throws IOException, TransferCancelledException {
623             HttpEntity entity = response.getEntity();
624             if (entity == null) {
625                 entity = new ByteArrayEntity(new byte[0]);
626             }
627 
628             long offset = 0L, length = entity.getContentLength();
629             Header rangeHeader = response.getFirstHeader(HttpHeaders.CONTENT_RANGE);
630             String range = rangeHeader != null ? rangeHeader.getValue() : null;
631             if (range != null) {
632                 Matcher m = CONTENT_RANGE_PATTERN.matcher(range);
633                 if (!m.matches()) {
634                     throw new IOException("Invalid Content-Range header for partial download: " + range);
635                 }
636                 offset = Long.parseLong(m.group(1));
637                 length = Long.parseLong(m.group(2)) + 1L;
638                 if (offset < 0L || offset >= length || (offset > 0L && offset != task.getResumeOffset())) {
639                     throw new IOException("Invalid Content-Range header for partial download from offset "
640                             + task.getResumeOffset() + ": " + range);
641                 }
642             }
643 
644             final boolean resume = offset > 0L;
645             final File dataFile = task.getDataFile();
646             if (dataFile == null) {
647                 try (InputStream is = entity.getContent()) {
648                     utilGet(task, is, true, length, resume);
649                     extractChecksums(response);
650                 }
651             } else {
652                 try (FileUtils.CollocatedTempFile tempFile = FileUtils.newTempFile(dataFile.toPath())) {
653                     task.setDataFile(tempFile.getPath().toFile(), resume);
654                     if (resume && Files.isRegularFile(dataFile.toPath())) {
655                         try (InputStream inputStream = Files.newInputStream(dataFile.toPath())) {
656                             Files.copy(inputStream, tempFile.getPath(), StandardCopyOption.REPLACE_EXISTING);
657                         }
658                     }
659                     try (InputStream is = entity.getContent()) {
660                         utilGet(task, is, true, length, resume);
661                     }
662                     tempFile.move();
663                 } finally {
664                     task.setDataFile(dataFile);
665                 }
666             }
667             if (task.getDataFile() != null) {
668                 Header lastModifiedHeader =
669                         response.getFirstHeader(HttpHeaders.LAST_MODIFIED); // note: Wagon also does first not last
670                 if (lastModifiedHeader != null) {
671                     Date lastModified = DateUtils.parseDate(lastModifiedHeader.getValue());
672                     if (lastModified != null) {
673                         Files.setLastModifiedTime(
674                                 task.getDataFile().toPath(), FileTime.fromMillis(lastModified.getTime()));
675                     }
676                 }
677             }
678             extractChecksums(response);
679         }
680 
681         private void extractChecksums(CloseableHttpResponse response) {
682             Map<String, String> checksums = extractXChecksums(response);
683             if (checksums == null) {
684                 checksums = extractNx2Checksums(response);
685             }
686             if (checksums != null) {
687                 checksums.forEach(task::setChecksum);
688             }
689         }
690     }
691 
692     private static Map<String, String> extractNx2Checksums(HttpResponse response) {
693         // Nexus-style, ETag: "{SHA1{d40d68ba1f88d8e9b0040f175a6ff41928abd5e7}}"
694         Header header = response.getFirstHeader(HttpHeaders.ETAG);
695         String etag = header != null ? header.getValue() : null;
696         if (etag != null) {
697             int start = etag.indexOf("SHA1{"), end = etag.indexOf("}", start + 5);
698             if (start >= 0 && end > start) {
699                 return Collections.singletonMap("SHA-1", etag.substring(start + 5, end));
700             }
701         }
702         return null;
703     }
704 
705     private static Map<String, String> extractXChecksums(HttpResponse response) {
706         String value;
707         HashMap<String, String> result = new HashMap<>();
708         // Central style: x-checksum-sha1: c74edb60ca2a0b57ef88d9a7da28f591e3d4ce7b
709         value = extractXChecksum(response, "x-checksum-sha1");
710         if (value != null) {
711             result.put("SHA-1", value);
712         }
713         // Central style: x-checksum-md5: 9ad0d8e3482767c122e85f83567b8ce6
714         value = extractXChecksum(response, "x-checksum-md5");
715         if (value != null) {
716             result.put("MD5", value);
717         }
718         if (!result.isEmpty()) {
719             return result;
720         }
721         // Google style: x-goog-meta-checksum-sha1: c74edb60ca2a0b57ef88d9a7da28f591e3d4ce7b
722         value = extractXChecksum(response, "x-goog-meta-checksum-sha1");
723         if (value != null) {
724             result.put("SHA-1", value);
725         }
726         // Central style: x-goog-meta-checksum-sha1: 9ad0d8e3482767c122e85f83567b8ce6
727         value = extractXChecksum(response, "x-goog-meta-checksum-md5");
728         if (value != null) {
729             result.put("MD5", value);
730         }
731 
732         return result.isEmpty() ? null : result;
733     }
734 
735     private static String extractXChecksum(HttpResponse response, String name) {
736         Header header = response.getFirstHeader(name);
737         return header != null ? header.getValue() : null;
738     }
739 
740     private class PutTaskEntity extends AbstractHttpEntity {
741 
742         private final PutTask task;
743 
744         PutTaskEntity(PutTask task) {
745             this.task = task;
746         }
747 
748         @Override
749         public boolean isRepeatable() {
750             return true;
751         }
752 
753         @Override
754         public boolean isStreaming() {
755             return false;
756         }
757 
758         @Override
759         public long getContentLength() {
760             return task.getDataLength();
761         }
762 
763         @Override
764         public InputStream getContent() throws IOException {
765             return task.newInputStream();
766         }
767 
768         @Override
769         public void writeTo(OutputStream os) throws IOException {
770             try {
771                 utilPut(task, os, false);
772             } catch (TransferCancelledException e) {
773                 throw (IOException) new InterruptedIOException().initCause(e);
774             }
775         }
776     }
777 
778     private static class ResolverServiceUnavailableRetryStrategy implements ServiceUnavailableRetryStrategy {
779         private final int retryCount;
780 
781         private final long retryInterval;
782 
783         private final long retryIntervalMax;
784 
785         private final Set<Integer> serviceUnavailableHttpCodes;
786 
787         /**
788          * Ugly, but forced by HttpClient API {@link ServiceUnavailableRetryStrategy}: the calls for
789          * {@link #retryRequest(HttpResponse, int, HttpContext)} and {@link #getRetryInterval()} are done by same
790          * thread and are actually done from spot that are very close to each other (almost subsequent calls).
791          */
792         private static final ThreadLocal<Long> RETRY_INTERVAL_HOLDER = new ThreadLocal<>();
793 
794         private ResolverServiceUnavailableRetryStrategy(
795                 int retryCount, long retryInterval, long retryIntervalMax, Set<Integer> serviceUnavailableHttpCodes) {
796             if (retryCount < 0) {
797                 throw new IllegalArgumentException("retryCount must be >= 0");
798             }
799             if (retryInterval < 0L) {
800                 throw new IllegalArgumentException("retryInterval must be >= 0");
801             }
802             if (retryIntervalMax < 0L) {
803                 throw new IllegalArgumentException("retryIntervalMax must be >= 0");
804             }
805             this.retryCount = retryCount;
806             this.retryInterval = retryInterval;
807             this.retryIntervalMax = retryIntervalMax;
808             this.serviceUnavailableHttpCodes = requireNonNull(serviceUnavailableHttpCodes);
809         }
810 
811         @Override
812         public boolean retryRequest(HttpResponse response, int executionCount, HttpContext context) {
813             final boolean retry = executionCount <= retryCount
814                     && (serviceUnavailableHttpCodes.contains(
815                             response.getStatusLine().getStatusCode()));
816             if (retry) {
817                 Long retryInterval = retryInterval(response, executionCount, context);
818                 if (retryInterval != null) {
819                     RETRY_INTERVAL_HOLDER.set(retryInterval);
820                     return true;
821                 }
822             }
823             RETRY_INTERVAL_HOLDER.remove();
824             return false;
825         }
826 
827         /**
828          * Calculates retry interval in milliseconds. If {@link HttpHeaders#RETRY_AFTER} header present, it obeys it.
829          * Otherwise, it returns {@link this#retryInterval} long value multiplied with {@code executionCount} (starts
830          * from 1 and goes 2, 3,...).
831          *
832          * @return Long representing the retry interval as millis, or {@code null} if the request should be failed.
833          */
834         private Long retryInterval(HttpResponse httpResponse, int executionCount, HttpContext httpContext) {
835             Long result = null;
836             Header header = httpResponse.getFirstHeader(HttpHeaders.RETRY_AFTER);
837             if (header != null && header.getValue() != null) {
838                 String headerValue = header.getValue();
839                 if (headerValue.contains(":")) { // is date when to retry
840                     Date when = DateUtils.parseDate(headerValue); // presumably future
841                     if (when != null) {
842                         result = Math.max(when.getTime() - System.currentTimeMillis(), 0L);
843                     }
844                 } else {
845                     try {
846                         result = Long.parseLong(headerValue) * 1000L; // is in seconds
847                     } catch (NumberFormatException e) {
848                         // fall through
849                     }
850                 }
851             }
852             if (result == null) {
853                 result = executionCount * this.retryInterval;
854             }
855             if (result > retryIntervalMax) {
856                 return null;
857             }
858             return result;
859         }
860 
861         @Override
862         public long getRetryInterval() {
863             Long ri = RETRY_INTERVAL_HOLDER.get();
864             if (ri == null) {
865                 return 0L;
866             }
867             RETRY_INTERVAL_HOLDER.remove();
868             return ri;
869         }
870     }
871 }