001package org.eclipse.aether.util.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.util.ArrayList;
023import java.util.Collection;
024import java.util.HashMap;
025import java.util.List;
026import java.util.Locale;
027import java.util.Map;
028import static java.util.Objects.requireNonNull;
029import java.util.StringTokenizer;
030import java.util.regex.Pattern;
031
032import org.eclipse.aether.repository.Proxy;
033import org.eclipse.aether.repository.ProxySelector;
034import org.eclipse.aether.repository.RemoteRepository;
035
036/**
037 * A simple proxy selector that selects the first matching proxy from a list of configured proxies.
038 */
039public final class DefaultProxySelector
040    implements ProxySelector
041{
042
043    private List<ProxyDef> proxies = new ArrayList<ProxyDef>();
044
045    /**
046     * Adds the specified proxy definition to the selector. Proxy definitions are ordered, the first matching proxy for
047     * a given repository will be used.
048     * 
049     * @param proxy The proxy definition to add, must not be {@code null}.
050     * @param nonProxyHosts The list of (case-insensitive) host names to exclude from proxying, may be {@code null}.
051     * @return This proxy selector for chaining, never {@code null}.
052     */
053    public DefaultProxySelector add( Proxy proxy, String nonProxyHosts )
054    {
055        requireNonNull( proxy, "proxy cannot be null" );
056        proxies.add( new ProxyDef( proxy, nonProxyHosts ) );
057
058        return this;
059    }
060
061    public Proxy getProxy( RemoteRepository repository )
062    {
063        Map<String, ProxyDef> candidates = new HashMap<String, ProxyDef>();
064
065        String host = repository.getHost();
066        for ( ProxyDef proxy : proxies )
067        {
068            if ( !proxy.nonProxyHosts.isNonProxyHost( host ) )
069            {
070                String key = proxy.proxy.getType().toLowerCase( Locale.ENGLISH );
071                if ( !candidates.containsKey( key ) )
072                {
073                    candidates.put( key, proxy );
074                }
075            }
076        }
077
078        String protocol = repository.getProtocol().toLowerCase( Locale.ENGLISH );
079
080        if ( "davs".equals( protocol ) )
081        {
082            protocol = "https";
083        }
084        else if ( "dav".equals( protocol ) )
085        {
086            protocol = "http";
087        }
088        else if ( protocol.startsWith( "dav:" ) )
089        {
090            protocol = protocol.substring( "dav:".length() );
091        }
092
093        ProxyDef proxy = candidates.get( protocol );
094        if ( proxy == null && "https".equals( protocol ) )
095        {
096            proxy = candidates.get( "http" );
097        }
098
099        return ( proxy != null ) ? proxy.proxy : null;
100    }
101
102    static class NonProxyHosts
103    {
104
105        private final Pattern[] patterns;
106
107        public NonProxyHosts( String nonProxyHosts )
108        {
109            List<Pattern> patterns = new ArrayList<Pattern>();
110            if ( nonProxyHosts != null )
111            {
112                for ( StringTokenizer tokenizer = new StringTokenizer( nonProxyHosts, "|" ); tokenizer.hasMoreTokens(); )
113                {
114                    String pattern = tokenizer.nextToken();
115                    pattern = pattern.replace( ".", "\\." ).replace( "*", ".*" );
116                    patterns.add( Pattern.compile( pattern, Pattern.CASE_INSENSITIVE ) );
117                }
118            }
119            this.patterns = patterns.toArray( new Pattern[patterns.size()] );
120        }
121
122        boolean isNonProxyHost( String host )
123        {
124            if ( host != null )
125            {
126                for ( Pattern pattern : patterns )
127                {
128                    if ( pattern.matcher( host ).matches() )
129                    {
130                        return true;
131                    }
132                }
133            }
134            return false;
135        }
136
137    }
138
139    static class ProxyDef
140    {
141
142        final Proxy proxy;
143
144        final NonProxyHosts nonProxyHosts;
145
146        public ProxyDef( Proxy proxy, String nonProxyHosts )
147        {
148            this.proxy = proxy;
149            this.nonProxyHosts = new NonProxyHosts( nonProxyHosts );
150        }
151
152    }
153
154}