MSHADE-307 dropping useDefaultConfiguration to make the behavior by default + supporting SPI loading for Filter and ResourceTransformer to enable 'add and enable' behavior/auto configuration

Author: rmannibucau

src/main/java/org/apache/maven/plugins/shade/mojo/ShadeMojo.java

@@ -81,6 +81,7 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.ServiceLoader;
 import java.util.Set;
 
 /**
@@ -367,15 +368,6 @@ public class ShadeMojo
     @Parameter( defaultValue = "false" )
     private boolean shadeTestJar;
 
-    /**
-     * Auto-configure the mojo to use common transformers (ServicesResourceTransformer, ManifestTransformer)
-     * and filters (META-INF/*.[SF,DSA,RSA]).
-     *
-     * @since 3.2.2
-     */
-    @Parameter( defaultValue = "false" )
-    private boolean useDefaultConfiguration;
-
     /**
      * @since 1.6
      */
@@ -785,11 +777,6 @@ private List<ResourceTransformer> getResourceTransformers()
 
     private List<ResourceTransformer> getDefaultResourceTransformers()
     {
-        if ( !useDefaultConfiguration )
-        {
-            return Collections.emptyList();
-        }
-
         final List<ResourceTransformer> transformers = new LinkedList<>();
         if ( missTransformer( ServicesResourceTransformer.class ) )
         {
@@ -801,6 +788,15 @@ private List<ResourceTransformer> getDefaultResourceTransformers()
             getLog().debug( "Adding ManifestResourceTransformer transformer" );
             transformers.add( new ManifestResourceTransformer() );
         }
+        for ( final ResourceTransformer transformer : ServiceLoader.load( ResourceTransformer.class ) )
+        {
+            if ( !missTransformer( transformer.getClass() ) )
+            {
+                continue;
+            }
+            getLog().debug( "Adding " + transformer.getClass().getName() + " transformer" );
+            transformers.add( transformer );
+        }
         return transformers;
     }
 
@@ -823,8 +819,8 @@ private boolean missTransformer( final Class<?> type )
     private List<Filter> getFilters()
         throws MojoExecutionException
     {
-        List<Filter> filters = new ArrayList<Filter>();
-        List<SimpleFilter> simpleFilters = new ArrayList<SimpleFilter>();
+        List<Filter> filters = new LinkedList<Filter>();
+        List<SimpleFilter> simpleFilters = new LinkedList<SimpleFilter>();
         Map<Artifact, ArtifactId> artifacts = null;
 
         if ( this.filters != null && this.filters.length > 0 )
@@ -848,39 +844,48 @@ private List<Filter> getFilters()
             }
         }
 
-        if ( useDefaultConfiguration )
+        // first check for backward compatibility this is not already configured explicitly
+        boolean addExclusion = true;
+        if ( this.filters != null )
         {
-            // first check for backward compatibility this is not already configured explicitly
-            boolean addExclusion = true;
-            if ( this.filters != null )
+            for ( final ArchiveFilter filter : this.filters )
             {
-                for ( final ArchiveFilter filter : this.filters )
+                if ( filter.getExcludes() != null
+                        && filter.getExcludes().contains( "META-INF/*.SF" )
+                        && filter.getExcludes().contains( "META-INF/*.DSA" )
+                        && filter.getExcludes().contains( "META-INF/*.RSA" )
+                        && "*:*".equals( filter.getArtifact() ) )
                 {
-                    if ( filter.getExcludes() != null
-                            && filter.getExcludes().contains( "META-INF/*.SF" )
-                            && filter.getExcludes().contains( "META-INF/*.DSA" )
-                            && filter.getExcludes().contains( "META-INF/*.RSA" )
-                            && "*:*".equals( filter.getArtifact() ) )
-                    {
-                        addExclusion = false;
-                        break;
-                    }
+                    addExclusion = false;
+                    break;
                 }
             }
-            if ( addExclusion )
-            {
-                getLog().debug( "Adding META-INF/*.SF, META-INF/*.DSA and META-INF/*.RSA exclusion" );
+        }
+        if ( addExclusion )
+        {
+            getLog().debug( "Adding META-INF/*.SF, META-INF/*.DSA and META-INF/*.RSA exclusion" );
 
-                if ( artifacts == null )
-                {
-                    artifacts = getArtifactIds();
-                }
-                simpleFilters.add( new SimpleFilter(
-                        getMatchingJars( artifacts , new ArtifactId( "*:*" ) ),
-                        Collections.<String>emptySet(),
-                        new HashSet<String>( Arrays.asList( "META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA" ) ) ) );
+            if ( artifacts == null )
+            {
+                artifacts = getArtifactIds();
             }
+            simpleFilters.add( new SimpleFilter(
+                    getMatchingJars( artifacts , new ArtifactId( "*:*" ) ),
+                    Collections.<String>emptySet(),
+                    new HashSet<String>( Arrays.asList( "META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA" ) ) ) );
+        }
 
+        for ( final Filter filter : ServiceLoader.load( Filter.class ) )
+        {
+            getLog().debug( "Adding " + filter.getClass().getName() + " filter" );
+            if ( SimpleFilter.class.isInstance( filter ) )
+            {
+                simpleFilters.add( SimpleFilter.class.cast( filter ) );
+            }
+            else
+            {
+                filters.add( filter );
+            }
         }
 
         filters.addAll( simpleFilters );

src/test/java/org/apache/maven/plugins/shade/mojo/ShadeMojoTest.java

@@ -69,9 +69,6 @@ public void testDefaultConfiguration() throws Exception
     {
         final ShadeMojo shadeMojo = new ShadeMojo();
         setProject(shadeMojo);
-        final Field useDefaultConfiguration = ShadeMojo.class.getDeclaredField("useDefaultConfiguration");
-        useDefaultConfiguration.setAccessible(true);
-        useDefaultConfiguration.set(shadeMojo, true);
 
         // default transformers are present
         final Method getResourceTransformers = ShadeMojo.class.getDeclaredMethod("getResourceTransformers");
@@ -198,10 +195,10 @@ public void testShadeWithFilter()
         List<Filter> filters = (List<Filter>) getFilters.invoke( mojo);
 
         // assertions - there must be one filter
-        assertEquals( 1, filters.size() );
+        assertEquals( 2, filters.size() );
 
         // the filter must be able to filter the binary and the sources jar
-        Filter filter = filters.get( 0 );
+        Filter filter = filters.get( 1 ); // 0 is the built-in META-INF/*
         assertTrue( filter.canFilter( new File( "myfaces-impl-2.0.1-SNAPSHOT.jar" ) ) ); // binary jar
         assertTrue( filter.canFilter( new File( "myfaces-impl-2.0.1-SNAPSHOT-sources.jar" ) ) ); // sources jar
     }