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.apache.rat.analysis.matchers;
20
21 import java.util.HashMap;
22 import java.util.HashSet;
23 import java.util.Map;
24 import java.util.Objects;
25 import java.util.Set;
26 import java.util.regex.Matcher;
27 import java.util.regex.Pattern;
28
29 import org.apache.commons.lang3.StringUtils;
30 import org.apache.rat.ConfigurationException;
31 import org.apache.rat.analysis.IHeaders;
32 import org.apache.rat.config.parameters.ComponentType;
33 import org.apache.rat.config.parameters.ConfigComponent;
34
35 /**
36 * Defines a factory to produce matchers for an SPDX tag. SPDX tag is of the
37 * format {@code SPDX-License-Identifier: short-name} where {@code short-name}
38 * matches the regex pattern [A-Za-z0-9\.\-]+
39 * <p>
40 * SPDX identifiers are specified by the Software Package Data Exchange(R) also
41 * known as SPDX(R) project from the Linux foundation.
42 * </p>
43 *
44 * @see <a href="https://spdx.dev/ids/">List of Ids at spdx.dev</a>
45 */
46 public class SPDXMatcherFactory {
47
48 /**
49 * The collection of all matchers produced by this factory.
50 */
51 private static final Map<String, SPDXMatcherFactory.Match> matchers = new HashMap<>();
52
53 /**
54 * The instance of this factory.
55 */
56 public static final SPDXMatcherFactory INSTANCE = new SPDXMatcherFactory();
57
58 static final String LICENSE_IDENTIFIER = "SPDX-License-Identifier:";
59
60 /**
61 * The regular expression to locate the SPDX license identifier in the text
62 * stream
63 */
64 private static Pattern groupSelector = Pattern.compile(".*"+LICENSE_IDENTIFIER+"\\s([A-Za-z0-9\\.\\-]+)");
65
66 /**
67 * The last matcer to match the line.
68 */
69 private Set<String> lastMatch;
70
71 private boolean checked;
72
73 private SPDXMatcherFactory() {
74 lastMatch = new HashSet<>();
75 }
76
77 private void reset() {
78 lastMatch.clear();
79 checked = false;
80 }
81
82 /**
83 * Creates the SPDX matcher.
84 *
85 * @param spdxId the SPDX name to match.
86 * @return a SPDX matcher.
87 */
88 public Match create(String spdxId) {
89 if (StringUtils.isBlank(spdxId)) {
90 throw new ConfigurationException("'SPDX' type matcher requires a name");
91 }
92 Match matcher = matchers.get(spdxId);
93 if (matcher == null) {
94 matcher = new Match(spdxId);
95 matchers.put(spdxId, matcher);
96 }
97 return matcher;
98 }
99
100 /**
101 * Each matcher calls this method to present the line it is working on.
102 *
103 * @param line The line the caller is looking at.
104 * @param caller the Match that is calling this method.
105 * @return true if the caller matches the text.
106 */
107 private boolean check(String line, Match caller) {
108 /*
109 If the line has not been seen yet see if we can extract the SPDX id from the line.
110 If so then see for each match extract and add the name to lastMatch
111 */
112 if (!checked) {
113 checked = true;
114 if (line.contains(LICENSE_IDENTIFIER)) {
115 Matcher matcher = groupSelector.matcher(line);
116 while (matcher.find()) {
117 lastMatch.add(matcher.group(1));
118 }
119 }
120 }
121 // see if the caller is in the lastMatch.
122 return lastMatch.contains(caller.spdxId);
123 }
124
125 @ConfigComponent(type = ComponentType.MATCHER, name = "spdx", desc = "Matches SPDX enclosed license identifier.")
126 public class Match extends AbstractHeaderMatcher {
127 @ConfigComponent(type = ComponentType.PARAMETER, name = "name", desc = "The SPDX identifier string")
128 String spdxId;
129
130 public String getName() {
131 return spdxId;
132 }
133
134 /**
135 * Constructor.
136 *
137 * @param spdxId A regular expression that matches the @{short-name} of the SPDX
138 * Identifier.
139 */
140 Match(final String spdxId) {
141 super("SPDX:" + spdxId);
142 Objects.requireNonNull(spdxId, "SpdxId is required");
143 this.spdxId = spdxId;
144 }
145
146 @Override
147 public boolean matches(IHeaders headers) {
148 return SPDXMatcherFactory.this.check(headers.raw(), this);
149 }
150
151 @Override
152 public void reset() {
153 super.reset();
154 SPDXMatcherFactory.this.reset();
155 }
156 }
157 }