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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.apache.maven.plugin;
20  
21  import java.io.File;
22  import java.util.Properties;
23  
24  import org.apache.maven.execution.MavenSession;
25  import org.apache.maven.plugin.descriptor.MojoDescriptor;
26  import org.apache.maven.plugin.descriptor.PluginDescriptor;
27  import org.apache.maven.project.MavenProject;
28  import org.apache.maven.project.path.PathTranslator;
29  import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
30  import org.codehaus.plexus.component.configurator.expression.TypeAwareExpressionEvaluator;
31  import org.codehaus.plexus.logging.Logger;
32  import org.codehaus.plexus.util.introspection.ReflectionValueExtractor;
33  
34  /**
35   * Evaluator for plugin parameters expressions. Content surrounded by <code>${</code> and <code>}</code> is evaluated.
36   * Recognized values are:
37   * <table border="1">
38   * <caption>Expression matrix</caption>
39   * <tr><th>expression</th>                     <th></th>               <th>evaluation result</th></tr>
40   * <tr><td><code>session</code></td>           <td></td>               <td>the actual {@link MavenSession}</td></tr>
41   * <tr><td><code>session.*</code></td>         <td>(since Maven 3)</td><td></td></tr>
42   * <tr><td><code>localRepository</code></td>   <td></td>
43   *                                             <td>{@link MavenSession#getLocalRepository()}</td></tr>
44   * <tr><td><code>reactorProjects</code></td>   <td></td>               <td>{@link MavenSession#getProjects()}</td></tr>
45   * <tr><td><code>repositorySystemSession</code></td><td> (since Maven 3)</td>
46   *                                             <td>{@link MavenSession#getRepositorySession()}</td></tr>
47   * <tr><td><code>project</code></td>           <td></td>
48   *                                             <td>{@link MavenSession#getCurrentProject()}</td></tr>
49   * <tr><td><code>project.*</code></td>         <td></td>               <td></td></tr>
50   * <tr><td><code>pom.*</code></td>             <td>(since Maven 3)</td><td>same as <code>project.*</code></td></tr>
51   * <tr><td><code>executedProject</code></td>   <td></td>
52   *                                             <td>{@link MavenProject#getExecutionProject()}</td></tr>
53   * <tr><td><code>settings</code></td>          <td></td>               <td>{@link MavenSession#getSettings()}</td></tr>
54   * <tr><td><code>settings.*</code></td>        <td></td>               <td></td></tr>
55   * <tr><td><code>basedir</code></td>           <td></td>
56   *                                             <td>{@link MavenSession#getExecutionRootDirectory()} or
57   *                                                 <code>System.getProperty( "user.dir" )</code> if null</td></tr>
58   * <tr><td><code>mojoExecution</code></td>     <td></td>               <td>the actual {@link MojoExecution}</td></tr>
59   * <tr><td><code>mojo</code></td>              <td>(since Maven 3)</td><td>same as <code>mojoExecution</code></td></tr>
60   * <tr><td><code>mojo.*</code></td>            <td>(since Maven 3)</td><td></td></tr>
61   * <tr><td><code>plugin</code></td>            <td>(since Maven 3)</td>
62   *                             <td>{@link MojoExecution#getMojoDescriptor()}.{@link MojoDescriptor#getPluginDescriptor()
63   *                                 getPluginDescriptor()}</td></tr>
64   * <tr><td><code>plugin.*</code></td>          <td></td>               <td></td></tr>
65   * <tr><td><code>*</code></td>                 <td></td>               <td>user properties</td></tr>
66   * <tr><td><code>*</code></td>                 <td></td>               <td>project properties</td></tr>
67   * <tr><td><code>*</code></td>                 <td></td>               <td>system properties</td></tr>
68   * </table>
69   * <i>Notice:</i> <code>reports</code> was supported in Maven 2.x but was removed in Maven 3
70   *
71   * @author Jason van Zyl
72   * @see MavenSession
73   * @see MojoExecution
74   */
75  public class PluginParameterExpressionEvaluator implements TypeAwareExpressionEvaluator {
76      private MavenSession session;
77  
78      private MojoExecution mojoExecution;
79  
80      private MavenProject project;
81  
82      private String basedir;
83  
84      private Properties properties;
85  
86      @Deprecated // TODO used by the Enforcer plugin
87      public PluginParameterExpressionEvaluator(
88              MavenSession session,
89              MojoExecution mojoExecution,
90              PathTranslator pathTranslator,
91              Logger logger,
92              MavenProject project,
93              Properties properties) {
94          this(session, mojoExecution);
95      }
96  
97      public PluginParameterExpressionEvaluator(MavenSession session) {
98          this(session, null);
99      }
100 
101     public PluginParameterExpressionEvaluator(MavenSession session, MojoExecution mojoExecution) {
102         this.session = session;
103         this.mojoExecution = mojoExecution;
104         this.properties = new Properties();
105         this.project = session.getCurrentProject();
106 
107         //
108         // Maven4: We may want to evaluate how this is used but we add these separate as the
109         // getExecutionProperties is deprecated in MavenSession.
110         //
111         this.properties.putAll(session.getUserProperties());
112         this.properties.putAll(session.getSystemProperties());
113 
114         String basedir = null;
115 
116         if (project != null) {
117             File projectFile = project.getBasedir();
118 
119             // this should always be the case for non-super POM instances...
120             if (projectFile != null) {
121                 basedir = projectFile.getAbsolutePath();
122             }
123         }
124 
125         if (basedir == null) {
126             basedir = session.getExecutionRootDirectory();
127         }
128 
129         if (basedir == null) {
130             basedir = System.getProperty("user.dir");
131         }
132 
133         this.basedir = basedir;
134     }
135 
136     @Override
137     public Object evaluate(String expr) throws ExpressionEvaluationException {
138         return evaluate(expr, null);
139     }
140 
141     @Override
142     @SuppressWarnings("checkstyle:methodlength")
143     public Object evaluate(String expr, Class<?> type) throws ExpressionEvaluationException {
144         Object value = null;
145 
146         if (expr == null) {
147             return null;
148         }
149 
150         String expression = stripTokens(expr);
151         if (expression.equals(expr)) {
152             int index = expr.indexOf("${");
153             if (index >= 0) {
154                 int lastIndex = expr.indexOf('}', index);
155                 if (lastIndex >= 0) {
156                     String retVal = expr.substring(0, index);
157 
158                     if ((index > 0) && (expr.charAt(index - 1) == '$')) {
159                         retVal += expr.substring(index + 1, lastIndex + 1);
160                     } else {
161                         Object subResult = evaluate(expr.substring(index, lastIndex + 1));
162 
163                         if (subResult != null) {
164                             retVal += subResult;
165                         } else {
166                             retVal += "$" + expr.substring(index + 1, lastIndex + 1);
167                         }
168                     }
169 
170                     retVal += evaluate(expr.substring(lastIndex + 1));
171                     return retVal;
172                 }
173             }
174 
175             // Was not an expression
176             if (expression.contains("$$")) {
177                 return expression.replaceAll("\\$\\$", "\\$");
178             } else {
179                 return expression;
180             }
181         }
182 
183         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
184 
185         if ("localRepository".equals(expression)) {
186             value = session.getLocalRepository();
187         } else if ("session".equals(expression)) {
188             value = session;
189         } else if (expression.startsWith("session")) {
190             try {
191                 int pathSeparator = expression.indexOf('/');
192 
193                 if (pathSeparator > 0) {
194                     String pathExpression = expression.substring(1, pathSeparator);
195                     value = ReflectionValueExtractor.evaluate(pathExpression, session);
196                     value = value + expression.substring(pathSeparator);
197                 } else {
198                     value = ReflectionValueExtractor.evaluate(expression.substring(1), session);
199                 }
200             } catch (Exception e) {
201                 // TODO don't catch exception
202                 throw new ExpressionEvaluationException(
203                         "Error evaluating plugin parameter expression: " + expression, e);
204             }
205         } else if ("reactorProjects".equals(expression)) {
206             value = session.getProjects();
207         } else if ("mojoExecution".equals(expression)) {
208             value = mojoExecution;
209         } else if ("project".equals(expression)) {
210             value = project;
211         } else if ("executedProject".equals(expression)) {
212             value = project.getExecutionProject();
213         } else if (expression.startsWith("project") || expression.startsWith("pom")) {
214             try {
215                 int pathSeparator = expression.indexOf('/');
216 
217                 if (pathSeparator > 0) {
218                     String pathExpression = expression.substring(0, pathSeparator);
219                     value = ReflectionValueExtractor.evaluate(pathExpression, project);
220                     value = value + expression.substring(pathSeparator);
221                 } else {
222                     value = ReflectionValueExtractor.evaluate(expression.substring(1), project);
223                 }
224             } catch (Exception e) {
225                 // TODO don't catch exception
226                 throw new ExpressionEvaluationException(
227                         "Error evaluating plugin parameter expression: " + expression, e);
228             }
229         } else if (expression.equals("repositorySystemSession")) {
230             value = session.getRepositorySession();
231         } else if (expression.equals("mojo")) {
232             value = mojoExecution;
233         } else if (expression.startsWith("mojo")) {
234             try {
235                 int pathSeparator = expression.indexOf('/');
236 
237                 if (pathSeparator > 0) {
238                     String pathExpression = expression.substring(1, pathSeparator);
239                     value = ReflectionValueExtractor.evaluate(pathExpression, mojoExecution);
240                     value = value + expression.substring(pathSeparator);
241                 } else {
242                     value = ReflectionValueExtractor.evaluate(expression.substring(1), mojoExecution);
243                 }
244             } catch (Exception e) {
245                 // TODO don't catch exception
246                 throw new ExpressionEvaluationException(
247                         "Error evaluating plugin parameter expression: " + expression, e);
248             }
249         } else if (expression.equals("plugin")) {
250             value = mojoDescriptor.getPluginDescriptor();
251         } else if (expression.startsWith("plugin")) {
252             try {
253                 int pathSeparator = expression.indexOf('/');
254 
255                 PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();
256 
257                 if (pathSeparator > 0) {
258                     String pathExpression = expression.substring(1, pathSeparator);
259                     value = ReflectionValueExtractor.evaluate(pathExpression, pluginDescriptor);
260                     value = value + expression.substring(pathSeparator);
261                 } else {
262                     value = ReflectionValueExtractor.evaluate(expression.substring(1), pluginDescriptor);
263                 }
264             } catch (Exception e) {
265                 throw new ExpressionEvaluationException(
266                         "Error evaluating plugin parameter expression: " + expression, e);
267             }
268         } else if ("settings".equals(expression)) {
269             value = session.getSettings();
270         } else if (expression.startsWith("settings")) {
271             try {
272                 int pathSeparator = expression.indexOf('/');
273 
274                 if (pathSeparator > 0) {
275                     String pathExpression = expression.substring(1, pathSeparator);
276                     value = ReflectionValueExtractor.evaluate(pathExpression, session.getSettings());
277                     value = value + expression.substring(pathSeparator);
278                 } else {
279                     value = ReflectionValueExtractor.evaluate(expression.substring(1), session.getSettings());
280                 }
281             } catch (Exception e) {
282                 // TODO don't catch exception
283                 throw new ExpressionEvaluationException(
284                         "Error evaluating plugin parameter expression: " + expression, e);
285             }
286         } else if ("basedir".equals(expression)) {
287             value = basedir;
288         } else if (expression.startsWith("basedir")) {
289             int pathSeparator = expression.indexOf('/');
290 
291             if (pathSeparator > 0) {
292                 value = basedir + expression.substring(pathSeparator);
293             }
294         }
295 
296         /*
297          * MNG-4312: We neither have reserved all of the above magic expressions nor is their set fixed/well-known (it
298          * gets occasionally extended by newer Maven versions). This imposes the risk for existing plugins to
299          * unintentionally use such a magic expression for an ordinary property. So here we check whether we
300          * ended up with a magic value that is not compatible with the type of the configured mojo parameter (a string
301          * could still be converted by the configurator so we leave those alone). If so, back off to evaluating the
302          * expression from properties only.
303          */
304         if (value != null && type != null && !(value instanceof String) && !isTypeCompatible(type, value)) {
305             value = null;
306         }
307 
308         if (value == null) {
309             // The CLI should win for defining properties
310 
311             if (properties != null) {
312                 // We will attempt to get nab a property as a way to specify a parameter
313                 // to a plugin. My particular case here is allowing the surefire plugin
314                 // to run a single test so I want to specify that class on the cli as
315                 // a parameter.
316 
317                 value = properties.getProperty(expression);
318             }
319 
320             if ((value == null) && ((project != null) && (project.getProperties() != null))) {
321                 value = project.getProperties().getProperty(expression);
322             }
323         }
324 
325         if (value instanceof String) {
326             // TODO without #, this could just be an evaluate call...
327 
328             String val = (String) value;
329 
330             int exprStartDelimiter = val.indexOf("${");
331 
332             if (exprStartDelimiter >= 0) {
333                 if (exprStartDelimiter > 0) {
334                     value = val.substring(0, exprStartDelimiter) + evaluate(val.substring(exprStartDelimiter));
335                 } else {
336                     value = evaluate(val.substring(exprStartDelimiter));
337                 }
338             }
339         }
340 
341         return value;
342     }
343 
344     private static boolean isTypeCompatible(Class<?> type, Object value) {
345         if (type.isInstance(value)) {
346             return true;
347         }
348         // likely Boolean -> boolean, Short -> int etc. conversions, it's not the problem case we try to avoid
349         return ((type.isPrimitive() || type.getName().startsWith("java.lang."))
350                 && value.getClass().getName().startsWith("java.lang."));
351     }
352 
353     private String stripTokens(String expr) {
354         if (expr.startsWith("${") && (expr.indexOf('}') == expr.length() - 1)) {
355             expr = expr.substring(2, expr.length() - 1);
356         }
357         return expr;
358     }
359 
360     @Override
361     public File alignToBaseDirectory(File file) {
362         // TODO Copied from the DefaultInterpolator. We likely want to resurrect the PathTranslator or at least a
363         // similar component for re-usage
364         if (file != null) {
365             if (file.isAbsolute()) {
366                 // path was already absolute, just normalize file separator and we're done
367             } else if (file.getPath().startsWith(File.separator)) {
368                 // drive-relative Windows path, don't align with project directory but with drive root
369                 file = file.getAbsoluteFile();
370             } else {
371                 // an ordinary relative path, align with project directory
372                 file = new File(new File(basedir, file.getPath()).toURI().normalize()).getAbsoluteFile();
373             }
374         }
375         return file;
376     }
377 }