View Javadoc
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.internal.impl.filter;
20  
21  import javax.inject.Inject;
22  import javax.inject.Named;
23  import javax.inject.Singleton;
24  
25  import java.util.Collections;
26  import java.util.HashMap;
27  import java.util.Map;
28  import java.util.stream.Collectors;
29  
30  import org.eclipse.aether.RepositorySystemSession;
31  import org.eclipse.aether.artifact.Artifact;
32  import org.eclipse.aether.impl.RemoteRepositoryFilterManager;
33  import org.eclipse.aether.metadata.Metadata;
34  import org.eclipse.aether.repository.RemoteRepository;
35  import org.eclipse.aether.spi.connector.filter.RemoteRepositoryFilter;
36  import org.eclipse.aether.spi.connector.filter.RemoteRepositoryFilterSource;
37  
38  import static java.util.Objects.requireNonNull;
39  
40  /**
41   * Default implementation of {@link RemoteRepositoryFilterManager}, it always returns a {@link RemoteRepositoryFilter}
42   * instance, even if no filter sources enabled/registered (then "always allow" instance).
43   * <p>
44   * The created {@link RemoteRepositoryFilter} instance is created once per session and cached.
45   *
46   * @since 1.9.0
47   */
48  @Singleton
49  @Named
50  public final class DefaultRemoteRepositoryFilterManager implements RemoteRepositoryFilterManager {
51      private static final String INSTANCE_KEY = DefaultRemoteRepositoryFilterManager.class.getName() + ".instance";
52  
53      private final Map<String, RemoteRepositoryFilterSource> sources;
54  
55      @Inject
56      public DefaultRemoteRepositoryFilterManager(Map<String, RemoteRepositoryFilterSource> sources) {
57          this.sources = requireNonNull(sources);
58      }
59  
60      @Override
61      public RemoteRepositoryFilter getRemoteRepositoryFilter(RepositorySystemSession session) {
62          return (RemoteRepositoryFilter) session.getData().computeIfAbsent(INSTANCE_KEY, () -> {
63              HashMap<String, RemoteRepositoryFilter> filters = new HashMap<>();
64              for (Map.Entry<String, RemoteRepositoryFilterSource> entry : sources.entrySet()) {
65                  RemoteRepositoryFilter filter = entry.getValue().getRemoteRepositoryFilter(session);
66                  if (filter != null) {
67                      filters.put(entry.getKey(), filter);
68                  }
69              }
70              if (!filters.isEmpty()) {
71                  return new Participants(filters);
72              } else {
73                  return null;
74              }
75          });
76      }
77  
78      /**
79       * {@link RemoteRepositoryFilter} instance when there are participant filters present. It evaluates into result
80       * using {@link Consensus}.
81       */
82      private static class Participants implements RemoteRepositoryFilter {
83          private final Map<String, RemoteRepositoryFilter> participants;
84  
85          private Participants(Map<String, RemoteRepositoryFilter> participants) {
86              this.participants = Collections.unmodifiableMap(participants);
87          }
88  
89          @Override
90          public RemoteRepositoryFilter.Result acceptArtifact(RemoteRepository remoteRepository, Artifact artifact) {
91              return new Consensus(
92                      participants.entrySet().stream().collect(Collectors.toMap(Map.Entry::getKey, e -> e.getValue()
93                              .acceptArtifact(remoteRepository, artifact))));
94          }
95  
96          @Override
97          public RemoteRepositoryFilter.Result acceptMetadata(RemoteRepository remoteRepository, Metadata metadata) {
98              return new Consensus(
99                      participants.entrySet().stream().collect(Collectors.toMap(Map.Entry::getKey, e -> e.getValue()
100                             .acceptMetadata(remoteRepository, metadata))));
101         }
102     }
103 
104     /**
105      * {@link RemoteRepositoryFilter.Result} based on "consensus". All participant have to "accept" to make this
106      * instance "accept".
107      */
108     private static class Consensus implements RemoteRepositoryFilter.Result {
109         private final boolean accepted;
110 
111         private final String reasoning;
112 
113         Consensus(Map<String, RemoteRepositoryFilter.Result> results) {
114             this.accepted = results.values().stream().allMatch(RemoteRepositoryFilter.Result::isAccepted);
115             this.reasoning = results.values().stream()
116                     .filter(r -> !r.isAccepted())
117                     .map(RemoteRepositoryFilter.Result::reasoning)
118                     .collect(Collectors.joining("; "));
119         }
120 
121         @Override
122         public boolean isAccepted() {
123             return accepted;
124         }
125 
126         @Override
127         public String reasoning() {
128             return reasoning;
129         }
130     }
131 }