View Javadoc
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:<table border="1" summary="Expression matrix">
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      @Deprecated //TODO used by the Enforcer plugin
87      public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution,
88                                                 PathTranslator pathTranslator, Logger logger, MavenProject project,
89                                                 Properties properties )
90      {
91          this( session, mojoExecution );
92      }
93  
94      public PluginParameterExpressionEvaluator( MavenSession session )
95      {
96          this( session, null );
97      }
98  
99      public PluginParameterExpressionEvaluator( MavenSession session, MojoExecution mojoExecution )
100     {
101         this.session = session;
102         this.mojoExecution = mojoExecution;
103         this.properties = new Properties();
104         this.project = session.getCurrentProject();
105 
106         //
107         // Maven4: We may want to evaluate how this is used but we add these separate as the 
108         // getExecutionProperties is deprecated in MavenSession.
109         //
110         this.properties.putAll( session.getUserProperties() );
111         this.properties.putAll( session.getSystemProperties() );
112         
113         String basedir = null;
114 
115         if ( project != null )
116         {
117             File projectFile = project.getBasedir();
118 
119             // this should always be the case for non-super POM instances...
120             if ( projectFile != null )
121             {
122                 basedir = projectFile.getAbsolutePath();
123             }
124         }
125 
126         if ( basedir == null )
127         {
128             basedir = session.getExecutionRootDirectory();
129         }
130 
131         if ( basedir == null )
132         {
133             basedir = System.getProperty( "user.dir" );
134         }
135 
136         this.basedir = basedir;
137     }
138 
139     @Override
140     public Object evaluate( String expr )
141         throws ExpressionEvaluationException
142     {
143         return evaluate( expr, null );
144     }
145 
146     @Override
147     public Object evaluate( String expr, Class<?> type )
148         throws ExpressionEvaluationException
149     {
150         Object value = null;
151 
152         if ( expr == null )
153         {
154             return null;
155         }
156 
157         String expression = stripTokens( expr );
158         if ( expression.equals( expr ) )
159         {
160             int index = expr.indexOf( "${" );
161             if ( index >= 0 )
162             {
163                 int lastIndex = expr.indexOf( '}', index );
164                 if ( lastIndex >= 0 )
165                 {
166                     String retVal = expr.substring( 0, index );
167 
168                     if ( ( index > 0 ) && ( expr.charAt( index - 1 ) == '$' ) )
169                     {
170                         retVal += expr.substring( index + 1, lastIndex + 1 );
171                     }
172                     else
173                     {
174                         Object subResult = evaluate( expr.substring( index, lastIndex + 1 ) );
175 
176                         if ( subResult != null )
177                         {
178                             retVal += subResult;
179                         }
180                         else
181                         {
182                             retVal += "$" + expr.substring( index + 1, lastIndex + 1 );
183                         }
184                     }
185 
186                     retVal += evaluate( expr.substring( lastIndex + 1 ) );
187                     return retVal;
188                 }
189             }
190 
191             // Was not an expression
192             if ( expression.contains( "$$" ) )
193             {
194                 return expression.replaceAll( "\\$\\$", "\\$" );
195             }
196             else
197             {
198                 return expression;
199             }
200         }
201 
202         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
203 
204         if ( "localRepository".equals( expression ) )
205         {
206             value = session.getLocalRepository();
207         }
208         else if ( "session".equals( expression ) )
209         {
210             value = session;
211         }
212         else if ( expression.startsWith( "session" ) )
213         {
214             try
215             {
216                 int pathSeparator = expression.indexOf( '/' );
217 
218                 if ( pathSeparator > 0 )
219                 {
220                     String pathExpression = expression.substring( 1, pathSeparator );
221                     value = ReflectionValueExtractor.evaluate( pathExpression, session );
222                     value = value + expression.substring( pathSeparator );
223                 }
224                 else
225                 {
226                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session );
227                 }
228             }
229             catch ( Exception e )
230             {
231                 // TODO don't catch exception
232                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
233                                                          e );
234             }
235         }
236         else if ( "reactorProjects".equals( expression ) )
237         {
238             value = session.getProjects();
239         }
240         else if ( "mojoExecution".equals( expression ) )
241         {
242             value = mojoExecution;
243         }
244         else if ( "project".equals( expression ) )
245         {
246             value = project;
247         }
248         else if ( "executedProject".equals( expression ) )
249         {
250             value = project.getExecutionProject();
251         }
252         else if ( expression.startsWith( "project" ) || expression.startsWith( "pom" ) )
253         {
254             try
255             {
256                 int pathSeparator = expression.indexOf( '/' );
257 
258                 if ( pathSeparator > 0 )
259                 {
260                     String pathExpression = expression.substring( 0, pathSeparator );
261                     value = ReflectionValueExtractor.evaluate( pathExpression, project );
262                     value = value + expression.substring( pathSeparator );
263                 }
264                 else
265                 {
266                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), project );
267                 }
268             }
269             catch ( Exception e )
270             {
271                 // TODO don't catch exception
272                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
273                                                          e );
274             }
275         }
276         else if ( expression.equals( "repositorySystemSession" ) )
277         {
278             value = session.getRepositorySession();
279         }
280         else if ( expression.equals( "mojo" ) )
281         {
282             value = mojoExecution;
283         }
284         else if ( expression.startsWith( "mojo" ) )
285         {
286             try
287             {
288                 int pathSeparator = expression.indexOf( '/' );
289 
290                 if ( pathSeparator > 0 )
291                 {
292                     String pathExpression = expression.substring( 1, pathSeparator );
293                     value = ReflectionValueExtractor.evaluate( pathExpression, mojoExecution );
294                     value = value + expression.substring( pathSeparator );
295                 }
296                 else
297                 {
298                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), mojoExecution );
299                 }
300             }
301             catch ( Exception e )
302             {
303                 // TODO don't catch exception
304                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
305                                                          e );
306             }
307         }
308         else if ( expression.equals( "plugin" ) )
309         {
310             value = mojoDescriptor.getPluginDescriptor();
311         }
312         else if ( expression.startsWith( "plugin" ) )
313         {
314             try
315             {
316                 int pathSeparator = expression.indexOf( '/' );
317 
318                 PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();
319 
320                 if ( pathSeparator > 0 )
321                 {
322                     String pathExpression = expression.substring( 1, pathSeparator );
323                     value = ReflectionValueExtractor.evaluate( pathExpression, pluginDescriptor );
324                     value = value + expression.substring( pathSeparator );
325                 }
326                 else
327                 {
328                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), pluginDescriptor );
329                 }
330             }
331             catch ( Exception e )
332             {
333                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
334                                                          e );
335             }
336         }
337         else if ( "settings".equals( expression ) )
338         {
339             value = session.getSettings();
340         }
341         else if ( expression.startsWith( "settings" ) )
342         {
343             try
344             {
345                 int pathSeparator = expression.indexOf( '/' );
346 
347                 if ( pathSeparator > 0 )
348                 {
349                     String pathExpression = expression.substring( 1, pathSeparator );
350                     value = ReflectionValueExtractor.evaluate( pathExpression, session.getSettings() );
351                     value = value + expression.substring( pathSeparator );
352                 }
353                 else
354                 {
355                     value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), session.getSettings() );
356                 }
357             }
358             catch ( Exception e )
359             {
360                 // TODO don't catch exception
361                 throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
362                                                          e );
363             }
364         }
365         else if ( "basedir".equals( expression ) )
366         {
367             value = basedir;
368         }
369         else if ( expression.startsWith( "basedir" ) )
370         {
371             int pathSeparator = expression.indexOf( '/' );
372 
373             if ( pathSeparator > 0 )
374             {
375                 value = basedir + expression.substring( pathSeparator );
376             }
377         }
378 
379         /*
380          * MNG-4312: We neither have reserved all of the above magic expressions nor is their set fixed/well-known (it
381          * gets occasionally extended by newer Maven versions). This imposes the risk for existing plugins to
382          * unintentionally use such a magic expression for an ordinary system property. So here we check whether we
383          * ended up with a magic value that is not compatible with the type of the configured mojo parameter (a string
384          * could still be converted by the configurator so we leave those alone). If so, back off to evaluating the
385          * expression from properties only.
386          */
387         if ( value != null && type != null && !( value instanceof String ) && !isTypeCompatible( type, value ) )
388         {
389             value = null;
390         }
391 
392         if ( value == null )
393         {
394             // The CLI should win for defining properties
395 
396             if ( properties != null )
397             {
398                 // We will attempt to get nab a system property as a way to specify a
399                 // parameter to a plugins. My particular case here is allowing the surefire
400                 // plugin to run a single test so I want to specify that class on the cli
401                 // as a parameter.
402 
403                 value = properties.getProperty( expression );
404             }
405 
406             if ( ( value == null ) && ( ( project != null ) && ( project.getProperties() != null ) ) )
407             {
408                 value = project.getProperties().getProperty( expression );
409             }
410 
411         }
412 
413         if ( value instanceof String )
414         {
415             // TODO without #, this could just be an evaluate call...
416 
417             String val = (String) value;
418 
419             int exprStartDelimiter = val.indexOf( "${" );
420 
421             if ( exprStartDelimiter >= 0 )
422             {
423                 if ( exprStartDelimiter > 0 )
424                 {
425                     value = val.substring( 0, exprStartDelimiter ) + evaluate( val.substring( exprStartDelimiter ) );
426                 }
427                 else
428                 {
429                     value = evaluate( val.substring( exprStartDelimiter ) );
430                 }
431             }
432         }
433 
434         return value;
435     }
436 
437     private static boolean isTypeCompatible( Class<?> type, Object value )
438     {
439         if ( type.isInstance( value ) )
440         {
441             return true;
442         }
443         // likely Boolean -> boolean, Short -> int etc. conversions, it's not the problem case we try to avoid
444         return ( ( type.isPrimitive() || type.getName().startsWith( "java.lang." ) )
445                         && value.getClass().getName().startsWith( "java.lang." ) );
446     }
447 
448     private String stripTokens( String expr )
449     {
450         if ( expr.startsWith( "${" ) && ( expr.indexOf( '}' ) == expr.length() - 1 ) )
451         {
452             expr = expr.substring( 2, expr.length() - 1 );
453         }
454         return expr;
455     }
456 
457     @Override
458     public File alignToBaseDirectory( File file )
459     {
460         // TODO Copied from the DefaultInterpolator. We likely want to resurrect the PathTranslator or at least a
461         // similar component for re-usage
462         if ( file != null )
463         {
464             if ( file.isAbsolute() )
465             {
466                 // path was already absolute, just normalize file separator and we're done
467             }
468             else if ( file.getPath().startsWith( File.separator ) )
469             {
470                 // drive-relative Windows path, don't align with project directory but with drive root
471                 file = file.getAbsoluteFile();
472             }
473             else
474             {
475                 // an ordinary relative path, align with project directory
476                 file = new File( new File( basedir, file.getPath() ).toURI().normalize() ).getAbsoluteFile();
477             }
478         }
479         return file;
480     }
481 
482 }