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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.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException;
30  import org.codehaus.plexus.component.configurator.expression.TypeAwareExpressionEvaluator;
31  import org.codehaus.plexus.util.introspection.ReflectionValueExtractor;
32  
33  /**
34   * Evaluator for plugin parameters expressions. Content surrounded by <code>${</code> and <code>}</code> is evaluated.
35   * Recognized values are:
36   * <table border="1">
37   * <caption>Expression matrix</caption>
38   * <tr><th>expression</th>                     <th></th>               <th>evaluation result</th></tr>
39   * <tr><td><code>session</code></td>           <td></td>               <td>the actual {@link MavenSession}</td></tr>
40   * <tr><td><code>session.*</code></td>         <td>(since Maven 3)</td><td></td></tr>
41   * <tr><td><code>localRepository</code></td>   <td></td>
42   *                                             <td>{@link MavenSession#getLocalRepository()}</td></tr>
43   * <tr><td><code>reactorProjects</code></td>   <td></td>               <td>{@link MavenSession#getProjects()}</td></tr>
44   * <tr><td><code>repositorySystemSession</code></td><td> (since Maven 3)</td>
45   *                                             <td>{@link MavenSession#getRepositorySession()}</td></tr>
46   * <tr><td><code>project</code></td>           <td></td>
47   *                                             <td>{@link MavenSession#getCurrentProject()}</td></tr>
48   * <tr><td><code>project.*</code></td>         <td></td>               <td></td></tr>
49   * <tr><td><code>pom.*</code></td>             <td>(since Maven 3)</td><td>same as <code>project.*</code></td></tr>
50   * <tr><td><code>executedProject</code></td>   <td></td>
51   *                                             <td>{@link MavenProject#getExecutionProject()}</td></tr>
52   * <tr><td><code>settings</code></td>          <td></td>               <td>{@link MavenSession#getSettings()}</td></tr>
53   * <tr><td><code>settings.*</code></td>        <td></td>               <td></td></tr>
54   * <tr><td><code>basedir</code></td>           <td></td>
55   *                                             <td>{@link MavenSession#getExecutionRootDirectory()} or
56   *                                                 <code>System.getProperty( "user.dir" )</code> if null</td></tr>
57   * <tr><td><code>mojoExecution</code></td>     <td></td>               <td>the actual {@link MojoExecution}</td></tr>
58   * <tr><td><code>mojo</code></td>              <td>(since Maven 3)</td><td>same as <code>mojoExecution</code></td></tr>
59   * <tr><td><code>mojo.*</code></td>            <td>(since Maven 3)</td><td></td></tr>
60   * <tr><td><code>plugin</code></td>            <td>(since Maven 3)</td>
61   *                             <td>{@link MojoExecution#getMojoDescriptor()}.{@link MojoDescriptor#getPluginDescriptor()
62   *                                 getPluginDescriptor()}</td></tr>
63   * <tr><td><code>plugin.*</code></td>          <td></td>               <td></td></tr>
64   * <tr><td><code>*</code></td>                 <td></td>               <td>system properties</td></tr>
65   * <tr><td><code>*</code></td>                 <td></td>               <td>project properties</td></tr>
66   * </table>
67   * <i>Notice:</i> <code>reports</code> was supported in Maven 2.x but was removed in Maven 3
68   *
69   * @author Jason van Zyl
70   * @see MavenSession
71   * @see MojoExecution
72   */
73  public class PluginParameterExpressionEvaluator
74      implements TypeAwareExpressionEvaluator
75  {
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      public PluginParameterExpressionEvaluator( MavenSession session )
87      {
88          this( session, null );
89      }
90  
91      public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution )
92      {
93          this.session = session;
94          this.mojoExecution = mojoExecution;
95          this.properties = new Properties();
96          this.project = session.getCurrentProject();
97  
98          //
99          // Maven4: We may want to evaluate how this is used but we add these separate as the
100         // getExecutionProperties is deprecated in MavenSession.
101         //
102         this.properties.putAll( session.getUserProperties() );
103         this.properties.putAll( session.getSystemProperties() );
104 
105         String basedir = null;
106 
107         if ( project != null )
108         {
109             File projectFile = project.getBasedir();
110 
111             // this should always be the case for non-super POM instances...
112             if ( projectFile != null )
113             {
114                 basedir = projectFile.getAbsolutePath();
115             }
116         }
117 
118         if ( basedir == null )
119         {
120             basedir = session.getExecutionRootDirectory();
121         }
122 
123         if ( basedir == null )
124         {
125             basedir = System.getProperty( "user.dir" );
126         }
127 
128         this.basedir = basedir;
129     }
130 
131     @Override
132     public Object evaluate( String expr )
133         throws ExpressionEvaluationException
134     {
135         return evaluate( expr, null );
136     }
137 
138     @Override
139     @SuppressWarnings( "checkstyle:methodlength" )
140     public Object evaluate( String expr, Class<?> type )
141         throws ExpressionEvaluationException
142     {
143         Object value = null;
144 
145         if ( expr == null )
146         {
147             return null;
148         }
149 
150         String expression = stripTokens( expr );
151         if ( expression.equals( expr ) )
152         {
153             int index = expr.indexOf( "${" );
154             if ( index >= 0 )
155             {
156                 int lastIndex = expr.indexOf( '}', index );
157                 if ( lastIndex >= 0 )
158                 {
159                     String retVal = expr.substring( 0, index );
160 
161                     if ( ( index > 0 ) && ( expr.charAt( index - 1 ) == '$' ) )
162                     {
163                         retVal += expr.substring( index + 1, lastIndex + 1 );
164                     }
165                     else
166                     {
167                         Object subResult = evaluate( expr.substring( index, lastIndex + 1 ) );
168 
169                         if ( subResult != null )
170                         {
171                             retVal += subResult;
172                         }
173                         else
174                         {
175                             retVal += "$" + expr.substring( index + 1, lastIndex + 1 );
176                         }
177                     }
178 
179                     retVal += evaluate( expr.substring( lastIndex + 1 ) );
180                     return retVal;
181                 }
182             }
183 
184             // Was not an expression
185             if ( expression.contains( "$$" ) )
186             {
187                 return expression.replaceAll( "\\$\\$", "\\$" );
188             }
189             else
190             {
191                 return expression;
192             }
193         }
194 
195         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
196 
197         if ( "localRepository".equals( expression ) )
198         {
199             value = session.getLocalRepository();
200         }
201         else if ( "session".equals( expression ) )
202         {
203             value = session;
204         }
205         else if ( expression.startsWith( "session" ) )
206         {
207             try
208             {
209                 int pathSeparator = expression.indexOf( '/' );
210 
211                 if ( pathSeparator > 0 )
212                 {
213                     String pathExpression = expression.substring( 1, pathSeparator );
214                     value = ReflectionValueExtractor.evaluate( pathExpression, session );
215                     value = value + expression.substring( pathSeparator );
216                 }
217                 else
218                 {
219                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session );
220                 }
221             }
222             catch ( Exception e )
223             {
224                 // TODO don't catch exception
225                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
226                                                          e );
227             }
228         }
229         else if ( "reactorProjects".equals( expression ) )
230         {
231             value = session.getProjects();
232         }
233         else if ( "project".equals( expression ) )
234         {
235             value = project;
236         }
237         else if ( "executedProject".equals( expression ) )
238         {
239             value = project.getExecutionProject();
240         }
241         else if ( expression.startsWith( "project" ) || expression.startsWith( "pom" ) )
242         {
243             try
244             {
245                 int pathSeparator = expression.indexOf( '/' );
246 
247                 if ( pathSeparator > 0 )
248                 {
249                     String pathExpression = expression.substring( 0, pathSeparator );
250                     value = ReflectionValueExtractor.evaluate( pathExpression, project );
251                     value = value + expression.substring( pathSeparator );
252                 }
253                 else
254                 {
255                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), project );
256                 }
257             }
258             catch ( Exception e )
259             {
260                 // TODO don't catch exception
261                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
262                                                          e );
263             }
264         }
265         else if ( expression.equals( "repositorySystemSession" ) )
266         {
267             value = session.getRepositorySession();
268         }
269         else if ( expression.equals( "mojo" ) || expression.equals( "mojoExecution" ) )
270         {
271             value = mojoExecution;
272         }
273         else if ( expression.startsWith( "mojo" ) )
274         {
275             try
276             {
277                 int pathSeparator = expression.indexOf( '/' );
278 
279                 if ( pathSeparator > 0 )
280                 {
281                     String pathExpression = expression.substring( 1, pathSeparator );
282                     value = ReflectionValueExtractor.evaluate( pathExpression, mojoExecution );
283                     value = value + expression.substring( pathSeparator );
284                 }
285                 else
286                 {
287                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), mojoExecution );
288                 }
289             }
290             catch ( Exception e )
291             {
292                 // TODO don't catch exception
293                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
294                                                          e );
295             }
296         }
297         else if ( expression.equals( "plugin" ) )
298         {
299             value = mojoDescriptor.getPluginDescriptor();
300         }
301         else if ( expression.startsWith( "plugin" ) )
302         {
303             try
304             {
305                 int pathSeparator = expression.indexOf( '/' );
306 
307                 PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();
308 
309                 if ( pathSeparator > 0 )
310                 {
311                     String pathExpression = expression.substring( 1, pathSeparator );
312                     value = ReflectionValueExtractor.evaluate( pathExpression, pluginDescriptor );
313                     value = value + expression.substring( pathSeparator );
314                 }
315                 else
316                 {
317                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), pluginDescriptor );
318                 }
319             }
320             catch ( Exception e )
321             {
322                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
323                                                          e );
324             }
325         }
326         else if ( "settings".equals( expression ) )
327         {
328             value = session.getSettings();
329         }
330         else if ( expression.startsWith( "settings" ) )
331         {
332             try
333             {
334                 int pathSeparator = expression.indexOf( '/' );
335 
336                 if ( pathSeparator > 0 )
337                 {
338                     String pathExpression = expression.substring( 1, pathSeparator );
339                     value = ReflectionValueExtractor.evaluate( pathExpression, session.getSettings() );
340                     value = value + expression.substring( pathSeparator );
341                 }
342                 else
343                 {
344                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session.getSettings() );
345                 }
346             }
347             catch ( Exception e )
348             {
349                 // TODO don't catch exception
350                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
351                                                          e );
352             }
353         }
354         else if ( "basedir".equals( expression ) )
355         {
356             value = basedir;
357         }
358         else if ( expression.startsWith( "basedir" ) )
359         {
360             int pathSeparator = expression.indexOf( '/' );
361 
362             if ( pathSeparator > 0 )
363             {
364                 value = basedir + expression.substring( pathSeparator );
365             }
366         }
367 
368         /*
369          * MNG-4312: We neither have reserved all of the above magic expressions nor is their set fixed/well-known (it
370          * gets occasionally extended by newer Maven versions). This imposes the risk for existing plugins to
371          * unintentionally use such a magic expression for an ordinary system property. So here we check whether we
372          * ended up with a magic value that is not compatible with the type of the configured mojo parameter (a string
373          * could still be converted by the configurator so we leave those alone). If so, back off to evaluating the
374          * expression from properties only.
375          */
376         if ( value != null && type != null && !( value instanceof String ) && !isTypeCompatible( type, value ) )
377         {
378             value = null;
379         }
380 
381         if ( value == null )
382         {
383             // The CLI should win for defining properties
384 
385             if ( properties != null )
386             {
387                 // We will attempt to get nab a system property as a way to specify a
388                 // parameter to a plugins. My particular case here is allowing the surefire
389                 // plugin to run a single test so I want to specify that class on the cli
390                 // as a parameter.
391 
392                 value = properties.getProperty( expression );
393             }
394 
395             if ( ( value == null ) && ( ( project != null ) && ( project.getProperties() != null ) ) )
396             {
397                 value = project.getProperties().getProperty( expression );
398             }
399 
400         }
401 
402         if ( value instanceof String )
403         {
404             // TODO without #, this could just be an evaluate call...
405 
406             String val = (String) value;
407 
408             int exprStartDelimiter = val.indexOf( "${" );
409 
410             if ( exprStartDelimiter >= 0 )
411             {
412                 if ( exprStartDelimiter > 0 )
413                 {
414                     value = val.substring( 0, exprStartDelimiter ) + evaluate( val.substring( exprStartDelimiter ) );
415                 }
416                 else
417                 {
418                     value = evaluate( val.substring( exprStartDelimiter ) );
419                 }
420             }
421         }
422 
423         return value;
424     }
425 
426     private static boolean isTypeCompatible( Class<?> type, Object value )
427     {
428         if ( type.isInstance( value ) )
429         {
430             return true;
431         }
432         // likely Boolean -> boolean, Short -> int etc. conversions, it's not the problem case we try to avoid
433         return ( ( type.isPrimitive() || type.getName().startsWith( "java.lang." ) )
434                         && value.getClass().getName().startsWith( "java.lang." ) );
435     }
436 
437     private String stripTokens( String expr )
438     {
439         if ( expr.startsWith( "${" ) && ( expr.indexOf( '}' ) == expr.length() - 1 ) )
440         {
441             expr = expr.substring( 2, expr.length() - 1 );
442         }
443         return expr;
444     }
445 
446     @Override
447     public File alignToBaseDirectory( File file )
448     {
449         // TODO Copied from the DefaultInterpolator. We likely want to resurrect the PathTranslator or at least a
450         // similar component for re-usage
451         if ( file != null )
452         {
453             if ( file.isAbsolute() )
454             {
455                 // path was already absolute, just normalize file separator and we're done
456             }
457             else if ( file.getPath().startsWith( File.separator ) )
458             {
459                 // drive-relative Windows path, don't align with project directory but with drive root
460                 file = file.getAbsoluteFile();
461             }
462             else
463             {
464                 // an ordinary relative path, align with project directory
465                 file = new File( new File( basedir, file.getPath() ).toURI().normalize() ).getAbsoluteFile();
466             }
467         }
468         return file;
469     }
470 
471 }