001package org.apache.maven.repository;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 *
012 *   http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import java.net.MalformedURLException;
023import java.net.URL;
024import java.util.List;
025
026import org.apache.maven.RepositoryUtils;
027import org.apache.maven.artifact.repository.ArtifactRepository;
028import org.apache.maven.settings.Mirror;
029import org.codehaus.plexus.component.annotations.Component;
030import org.codehaus.plexus.util.StringUtils;
031
032@Component( role = MirrorSelector.class )
033public class DefaultMirrorSelector
034    implements MirrorSelector
035{
036
037    private static final String WILDCARD = "*";
038
039    private static final String EXTERNAL_WILDCARD = "external:*";
040
041    public Mirror getMirror( ArtifactRepository repository, List<Mirror> mirrors )
042    {
043        String repoId = repository.getId();
044
045        if ( repoId != null && mirrors != null )
046        {
047            for ( Mirror mirror : mirrors )
048            {
049                if ( repoId.equals( mirror.getMirrorOf() ) && matchesLayout( repository, mirror ) )
050                {
051                    return mirror;
052                }
053            }
054
055            for ( Mirror mirror : mirrors )
056            {
057                if ( matchPattern( repository, mirror.getMirrorOf() ) && matchesLayout( repository, mirror ) )
058                {
059                    return mirror;
060                }
061            }
062        }
063
064        return null;
065    }
066
067    /**
068     * This method checks if the pattern matches the originalRepository. Valid patterns: * =
069     * everything external:* = everything not on the localhost and not file based. repo,repo1 = repo
070     * or repo1 *,!repo1 = everything except repo1
071     *
072     * @param originalRepository to compare for a match.
073     * @param pattern used for match. Currently only '*' is supported.
074     * @return true if the repository is a match to this pattern.
075     */
076    static boolean matchPattern( ArtifactRepository originalRepository, String pattern )
077    {
078        boolean result = false;
079        String originalId = originalRepository.getId();
080
081        // simple checks first to short circuit processing below.
082        if ( WILDCARD.equals( pattern ) || pattern.equals( originalId ) )
083        {
084            result = true;
085        }
086        else
087        {
088            // process the list
089            String[] repos = pattern.split( "," );
090            for ( String repo : repos )
091            {
092                repo = repo.trim();
093                // see if this is a negative match
094                if ( repo.length() > 1 && repo.startsWith( "!" ) )
095                {
096                    if ( repo.substring( 1 ).equals( originalId ) )
097                    {
098                        // explicitly exclude. Set result and stop processing.
099                        result = false;
100                        break;
101                    }
102                }
103                // check for exact match
104                else if ( repo.equals( originalId ) )
105                {
106                    result = true;
107                    break;
108                }
109                // check for external:*
110                else if ( EXTERNAL_WILDCARD.equals( repo ) && isExternalRepo( originalRepository ) )
111                {
112                    result = true;
113                    // don't stop processing in case a future segment explicitly excludes this repo
114                }
115                else if ( WILDCARD.equals( repo ) )
116                {
117                    result = true;
118                    // don't stop processing in case a future segment explicitly excludes this repo
119                }
120            }
121        }
122        return result;
123    }
124
125    /**
126     * Checks the URL to see if this repository refers to an external repository
127     *
128     * @param originalRepository
129     * @return true if external.
130     */
131    static boolean isExternalRepo( ArtifactRepository originalRepository )
132    {
133        try
134        {
135            URL url = new URL( originalRepository.getUrl() );
136            return !( url.getHost().equals( "localhost" ) || url.getHost().equals( "127.0.0.1" )
137                            || url.getProtocol().equals( "file" ) );
138        }
139        catch ( MalformedURLException e )
140        {
141            // bad url just skip it here. It should have been validated already, but the wagon lookup will deal with it
142            return false;
143        }
144    }
145
146    static boolean matchesLayout( ArtifactRepository repository, Mirror mirror )
147    {
148        return matchesLayout( RepositoryUtils.getLayout( repository ), mirror.getMirrorOfLayouts() );
149    }
150
151    /**
152     * Checks whether the layouts configured for a mirror match with the layout of the repository.
153     *
154     * @param repoLayout The layout of the repository, may be {@code null}.
155     * @param mirrorLayout The layouts supported by the mirror, may be {@code null}.
156     * @return {@code true} if the layouts associated with the mirror match the layout of the original repository,
157     *         {@code false} otherwise.
158     */
159    static boolean matchesLayout( String repoLayout, String mirrorLayout )
160    {
161        boolean result = false;
162
163        // simple checks first to short circuit processing below.
164        if ( StringUtils.isEmpty( mirrorLayout ) || WILDCARD.equals( mirrorLayout ) )
165        {
166            result = true;
167        }
168        else if ( mirrorLayout.equals( repoLayout ) )
169        {
170            result = true;
171        }
172        else
173        {
174            // process the list
175            String[] layouts = mirrorLayout.split( "," );
176            for ( String layout : layouts )
177            {
178                // see if this is a negative match
179                if ( layout.length() > 1 && layout.startsWith( "!" ) )
180                {
181                    if ( layout.substring( 1 ).equals( repoLayout ) )
182                    {
183                        // explicitly exclude. Set result and stop processing.
184                        result = false;
185                        break;
186                    }
187                }
188                // check for exact match
189                else if ( layout.equals( repoLayout ) )
190                {
191                    result = true;
192                    break;
193                }
194                else if ( WILDCARD.equals( layout ) )
195                {
196                    result = true;
197                    // don't stop processing in case a future segment explicitly excludes this repo
198                }
199            }
200        }
201
202        return result;
203    }
204
205}