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1   package org.apache.maven.plugin;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *  http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import java.io.File;
23  import java.util.Properties;
24  
25  import org.apache.maven.execution.MavenSession;
26  import org.apache.maven.plugin.descriptor.MojoDescriptor;
27  import org.apache.maven.plugin.descriptor.PluginDescriptor;
28  import org.apache.maven.project.MavenProject;
29  import org.apache.maven.project.path.PathTranslator;
30  import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
31  import org.codehaus.plexus.component.configurator.expression.TypeAwareExpressionEvaluator;
32  import org.codehaus.plexus.logging.Logger;
33  import org.codehaus.plexus.util.introspection.ReflectionValueExtractor;
34  
35  /**
36   * Evaluator for plugin parameters expressions. Content surrounded by <code>${</code> and <code>}</code> is evaluated.
37   * Recognized values are:
38   * <table border="1">
39   * <caption>Expression matrix</caption>
40   * <tr><th>expression</th>                     <th></th>               <th>evaluation result</th></tr>
41   * <tr><td><code>session</code></td>           <td></td>               <td>the actual {@link MavenSession}</td></tr>
42   * <tr><td><code>session.*</code></td>         <td>(since Maven 3)</td><td></td></tr>
43   * <tr><td><code>localRepository</code></td>   <td></td>
44   *                                             <td>{@link MavenSession#getLocalRepository()}</td></tr>
45   * <tr><td><code>reactorProjects</code></td>   <td></td>               <td>{@link MavenSession#getProjects()}</td></tr>
46   * <tr><td><code>repositorySystemSession</code></td><td> (since Maven 3)</td>
47   *                                             <td>{@link MavenSession#getRepositorySession()}</td></tr>
48   * <tr><td><code>project</code></td>           <td></td>
49   *                                             <td>{@link MavenSession#getCurrentProject()}</td></tr>
50   * <tr><td><code>project.*</code></td>         <td></td>               <td></td></tr>
51   * <tr><td><code>pom.*</code></td>             <td>(since Maven 3)</td><td>same as <code>project.*</code></td></tr>
52   * <tr><td><code>executedProject</code></td>   <td></td>
53   *                                             <td>{@link MavenProject#getExecutionProject()}</td></tr>
54   * <tr><td><code>settings</code></td>          <td></td>               <td>{@link MavenSession#getSettings()}</td></tr>
55   * <tr><td><code>settings.*</code></td>        <td></td>               <td></td></tr>
56   * <tr><td><code>basedir</code></td>           <td></td>
57   *                                             <td>{@link MavenSession#getExecutionRootDirectory()} or 
58   *                                                 <code>System.getProperty( "user.dir" )</code> if null</td></tr>
59   * <tr><td><code>mojoExecution</code></td>     <td></td>               <td>the actual {@link MojoExecution}</td></tr>
60   * <tr><td><code>mojo</code></td>              <td>(since Maven 3)</td><td>same as <code>mojoExecution</code></td></tr>
61   * <tr><td><code>mojo.*</code></td>            <td>(since Maven 3)</td><td></td></tr>
62   * <tr><td><code>plugin</code></td>            <td>(since Maven 3)</td>
63   *                             <td>{@link MojoExecution#getMojoDescriptor()}.{@link MojoDescriptor#getPluginDescriptor()
64   *                                 getPluginDescriptor()}</td></tr>
65   * <tr><td><code>plugin.*</code></td>          <td></td>               <td></td></tr>
66   * <tr><td><code>*</code></td>                 <td></td>               <td>system properties</td></tr>
67   * <tr><td><code>*</code></td>                 <td></td>               <td>project 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
76      implements TypeAwareExpressionEvaluator
77  {
78      private MavenSession session;
79  
80      private MojoExecution mojoExecution;
81  
82      private MavenProject project;
83  
84      private String basedir;
85  
86      private Properties properties;
87  
88      @Deprecated //TODO used by the Enforcer plugin
89      public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution,
90                                                 PathTranslator pathTranslator, Logger logger, MavenProject project,
91                                                 Properties properties )
92      {
93          this( session, mojoExecution );
94      }
95  
96      public PluginParameterExpressionEvaluator( MavenSession session )
97      {
98          this( session, null );
99      }
100 
101     public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution )
102     {
103         this.session = session;
104         this.mojoExecution = mojoExecution;
105         this.properties = new Properties();
106         this.project = session.getCurrentProject();
107 
108         //
109         // Maven4: We may want to evaluate how this is used but we add these separate as the 
110         // getExecutionProperties is deprecated in MavenSession.
111         //
112         this.properties.putAll( session.getUserProperties() );
113         this.properties.putAll( session.getSystemProperties() );
114         
115         String basedir = null;
116 
117         if ( project != null )
118         {
119             File projectFile = project.getBasedir();
120 
121             // this should always be the case for non-super POM instances...
122             if ( projectFile != null )
123             {
124                 basedir = projectFile.getAbsolutePath();
125             }
126         }
127 
128         if ( basedir == null )
129         {
130             basedir = session.getExecutionRootDirectory();
131         }
132 
133         if ( basedir == null )
134         {
135             basedir = System.getProperty( "user.dir" );
136         }
137 
138         this.basedir = basedir;
139     }
140 
141     @Override
142     public Object evaluate( String expr )
143         throws ExpressionEvaluationException
144     {
145         return evaluate( expr, null );
146     }
147 
148     @Override
149     @SuppressWarnings( "checkstyle:methodlength" )
150     public Object evaluate( String expr, Class<?> type )
151         throws ExpressionEvaluationException
152     {
153         Object value = null;
154 
155         if ( expr == null )
156         {
157             return null;
158         }
159 
160         String expression = stripTokens( expr );
161         if ( expression.equals( expr ) )
162         {
163             int index = expr.indexOf( "${" );
164             if ( index >= 0 )
165             {
166                 int lastIndex = expr.indexOf( '}', index );
167                 if ( lastIndex >= 0 )
168                 {
169                     String retVal = expr.substring( 0, index );
170 
171                     if ( ( index > 0 ) && ( expr.charAt( index - 1 ) == '$' ) )
172                     {
173                         retVal += expr.substring( index + 1, lastIndex + 1 );
174                     }
175                     else
176                     {
177                         Object subResult = evaluate( expr.substring( index, lastIndex + 1 ) );
178 
179                         if ( subResult != null )
180                         {
181                             retVal += subResult;
182                         }
183                         else
184                         {
185                             retVal += "$" + expr.substring( index + 1, lastIndex + 1 );
186                         }
187                     }
188 
189                     retVal += evaluate( expr.substring( lastIndex + 1 ) );
190                     return retVal;
191                 }
192             }
193 
194             // Was not an expression
195             return expression.replace( "$$", "$" );
196         }
197 
198         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
199 
200         if ( "localRepository".equals( expression ) )
201         {
202             value = session.getLocalRepository();
203         }
204         else if ( "session".equals( expression ) )
205         {
206             value = session;
207         }
208         else if ( expression.startsWith( "session" ) )
209         {
210             try
211             {
212                 int pathSeparator = expression.indexOf( '/' );
213 
214                 if ( pathSeparator > 0 )
215                 {
216                     String pathExpression = expression.substring( 1, pathSeparator );
217                     value = ReflectionValueExtractor.evaluate( pathExpression, session );
218                     value = value + expression.substring( pathSeparator );
219                 }
220                 else
221                 {
222                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session );
223                 }
224             }
225             catch ( Exception e )
226             {
227                 // TODO don't catch exception
228                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
229                                                          e );
230             }
231         }
232         else if ( "reactorProjects".equals( expression ) )
233         {
234             value = session.getProjects();
235         }
236         else if ( "mojoExecution".equals( expression ) )
237         {
238             value = mojoExecution;
239         }
240         else if ( "project".equals( expression ) )
241         {
242             value = project;
243         }
244         else if ( "executedProject".equals( expression ) )
245         {
246             value = project.getExecutionProject();
247         }
248         else if ( expression.startsWith( "project" ) || expression.startsWith( "pom" ) )
249         {
250             try
251             {
252                 int pathSeparator = expression.indexOf( '/' );
253 
254                 if ( pathSeparator > 0 )
255                 {
256                     String pathExpression = expression.substring( 0, pathSeparator );
257                     value = ReflectionValueExtractor.evaluate( pathExpression, project );
258                     value = value + expression.substring( pathSeparator );
259                 }
260                 else
261                 {
262                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), project );
263                 }
264             }
265             catch ( Exception e )
266             {
267                 // TODO don't catch exception
268                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
269                                                          e );
270             }
271         }
272         else if ( expression.equals( "repositorySystemSession" ) )
273         {
274             value = session.getRepositorySession();
275         }
276         else if ( expression.equals( "mojo" ) )
277         {
278             value = mojoExecution;
279         }
280         else if ( expression.startsWith( "mojo" ) )
281         {
282             try
283             {
284                 int pathSeparator = expression.indexOf( '/' );
285 
286                 if ( pathSeparator > 0 )
287                 {
288                     String pathExpression = expression.substring( 1, pathSeparator );
289                     value = ReflectionValueExtractor.evaluate( pathExpression, mojoExecution );
290                     value = value + expression.substring( pathSeparator );
291                 }
292                 else
293                 {
294                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), mojoExecution );
295                 }
296             }
297             catch ( Exception e )
298             {
299                 // TODO don't catch exception
300                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
301                                                          e );
302             }
303         }
304         else if ( expression.equals( "plugin" ) )
305         {
306             value = mojoDescriptor.getPluginDescriptor();
307         }
308         else if ( expression.startsWith( "plugin" ) )
309         {
310             try
311             {
312                 int pathSeparator = expression.indexOf( '/' );
313 
314                 PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();
315 
316                 if ( pathSeparator > 0 )
317                 {
318                     String pathExpression = expression.substring( 1, pathSeparator );
319                     value = ReflectionValueExtractor.evaluate( pathExpression, pluginDescriptor );
320                     value = value + expression.substring( pathSeparator );
321                 }
322                 else
323                 {
324                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), pluginDescriptor );
325                 }
326             }
327             catch ( Exception e )
328             {
329                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
330                                                          e );
331             }
332         }
333         else if ( "settings".equals( expression ) )
334         {
335             value = session.getSettings();
336         }
337         else if ( expression.startsWith( "settings" ) )
338         {
339             try
340             {
341                 int pathSeparator = expression.indexOf( '/' );
342 
343                 if ( pathSeparator > 0 )
344                 {
345                     String pathExpression = expression.substring( 1, pathSeparator );
346                     value = ReflectionValueExtractor.evaluate( pathExpression, session.getSettings() );
347                     value = value + expression.substring( pathSeparator );
348                 }
349                 else
350                 {
351                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session.getSettings() );
352                 }
353             }
354             catch ( Exception e )
355             {
356                 // TODO don't catch exception
357                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
358                                                          e );
359             }
360         }
361         else if ( "basedir".equals( expression ) )
362         {
363             value = basedir;
364         }
365         else if ( expression.startsWith( "basedir" ) )
366         {
367             int pathSeparator = expression.indexOf( '/' );
368 
369             if ( pathSeparator > 0 )
370             {
371                 value = basedir + expression.substring( pathSeparator );
372             }
373         }
374 
375         /*
376          * MNG-4312: We neither have reserved all of the above magic expressions nor is their set fixed/well-known (it
377          * gets occasionally extended by newer Maven versions). This imposes the risk for existing plugins to
378          * unintentionally use such a magic expression for an ordinary system property. So here we check whether we
379          * ended up with a magic value that is not compatible with the type of the configured mojo parameter (a string
380          * could still be converted by the configurator so we leave those alone). If so, back off to evaluating the
381          * expression from properties only.
382          */
383         if ( value != null && type != null && !( value instanceof String ) && !isTypeCompatible( type, value ) )
384         {
385             value = null;
386         }
387 
388         if ( value == null )
389         {
390             // The CLI should win for defining properties
391 
392             if ( properties != null )
393             {
394                 // We will attempt to get nab a system property as a way to specify a
395                 // parameter to a plugins. My particular case here is allowing the surefire
396                 // plugin to run a single test so I want to specify that class on the cli
397                 // as a parameter.
398 
399                 value = properties.getProperty( expression );
400             }
401 
402             if ( ( value == null ) && ( ( project != null ) && ( project.getProperties() != null ) ) )
403             {
404                 value = project.getProperties().getProperty( expression );
405             }
406 
407         }
408 
409         if ( value instanceof String )
410         {
411             // TODO without #, this could just be an evaluate call...
412 
413             String val = (String) value;
414 
415             int exprStartDelimiter = val.indexOf( "${" );
416 
417             if ( exprStartDelimiter >= 0 )
418             {
419                 if ( exprStartDelimiter > 0 )
420                 {
421                     value = val.substring( 0, exprStartDelimiter ) + evaluate( val.substring( exprStartDelimiter ) );
422                 }
423                 else
424                 {
425                     value = evaluate( val.substring( exprStartDelimiter ) );
426                 }
427             }
428         }
429 
430         return value;
431     }
432 
433     private static boolean isTypeCompatible( Class<?> type, Object value )
434     {
435         if ( type.isInstance( value ) )
436         {
437             return true;
438         }
439         // likely Boolean -> boolean, Short -> int etc. conversions, it's not the problem case we try to avoid
440         return ( ( type.isPrimitive() || type.getName().startsWith( "java.lang." ) )
441                         && value.getClass().getName().startsWith( "java.lang." ) );
442     }
443 
444     private String stripTokens( String expr )
445     {
446         if ( expr.startsWith( "${" ) && ( expr.indexOf( '}' ) == expr.length() - 1 ) )
447         {
448             expr = expr.substring( 2, expr.length() - 1 );
449         }
450         return expr;
451     }
452 
453     @Override
454     public File alignToBaseDirectory( File file )
455     {
456         // TODO Copied from the DefaultInterpolator. We likely want to resurrect the PathTranslator or at least a
457         // similar component for re-usage
458         if ( file != null )
459         {
460             if ( file.isAbsolute() )
461             {
462                 // path was already absolute, just normalize file separator and we're done
463             }
464             else if ( file.getPath().startsWith( File.separator ) )
465             {
466                 // drive-relative Windows path, don't align with project directory but with drive root
467                 file = file.getAbsoluteFile();
468             }
469             else
470             {
471                 // an ordinary relative path, align with project directory
472                 file = new File( new File( basedir, file.getPath() ).toURI().normalize() ).getAbsoluteFile();
473             }
474         }
475         return file;
476     }
477 
478 }