PR: MNG-178

Submitted by: Kenney Westerhof
Reviewed by:  Brett Porter

add filtering support to the resources
(applied with modifications)



git-svn-id: https://svn.apache.org/repos/asf/maven/components/trunk@191749 13f79535-47bb-0310-9956-ffa450edef68

maven-plugins/maven-resources-plugin/src/main/java/org/apache/maven/plugin/resources/PropertyUtils.java

@@ -0,0 +1,147 @@
+package org.apache.maven.plugin.resources;
+
+/*
+ * Copyright 2001-2005 The Apache Software Foundation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import org.codehaus.plexus.util.IOUtil;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.util.Enumeration;
+import java.util.Properties;
+
+
+/**
+ * @author <a href="mailto:kenney@neonics.com">Kenney Westerhof</a>
+ * @version $Id$
+ */
+public final class PropertyUtils
+{
+    private PropertyUtils()
+    {
+        // prevent instantiation
+    }
+
+    /**
+     * Reads a property file, resolving all internal variables.
+     *
+     * @param propfile The property file to load
+     * @param fail wheter to throw an exception when the file cannot be loaded or to return null
+     * @param useSystemProps wheter to incorporate System.getProperties settings into the returned Properties object.
+     * @return the loaded and fully resolved Properties object
+     */
+    public static Properties loadPropertyFile( File propfile, boolean fail, boolean useSystemProps )
+        throws IOException
+    {
+        Properties props = new Properties();
+
+        if ( useSystemProps )
+        {
+            props = new Properties( System.getProperties() );
+        }
+
+        if ( propfile.exists() )
+        {
+            FileInputStream inStream = new FileInputStream( propfile );
+            try
+            {
+                props.load( inStream );
+            }
+            finally
+            {
+                IOUtil.close( inStream );
+            }
+        }
+        else if ( fail )
+        {
+            throw new FileNotFoundException( propfile.toString() );
+        }
+
+        for ( Enumeration n = props.propertyNames(); n.hasMoreElements(); )
+        {
+            String k = (String) n.nextElement();
+            props.setProperty( k, getPropertyValue( k, props ) );
+        }
+
+        return props;
+    }
+
+
+    /**
+     * Retrieves a property value, replacing values like ${token}
+     * using the Properties to look them up.
+     *
+     * It will leave unresolved properties alone, trying for System
+     * properties, and implements reparsing (in the case that
+     * the value of a property contains a key), and will
+     * not loop endlessly on a pair like
+     * test = ${test}.
+     */
+    private static String getPropertyValue( String k, Properties p )
+    {
+        // This can also be done using InterpolationFilterReader,
+        // but it requires reparsing the file over and over until
+        // it doesn't change.
+
+        String v = p.getProperty( k );
+        String ret = "";
+        int idx, idx2;
+
+        while ( ( idx = v.indexOf( "${" ) ) >= 0 )
+        {
+            // append prefix to result
+            ret += v.substring( 0, idx );
+
+            // strip prefix from original
+            v = v.substring( idx + 2 );
+
+            // if no matching } then bail
+            if ( ( idx2 = v.indexOf( '}' ) ) < 0 )
+            {
+                break;
+            }
+
+            // strip out the key and resolve it
+            // resolve the key/value for the ${statement}
+            String nk = v.substring( 0, idx2 );
+            v = v.substring( idx2 + 1 );
+            String nv = p.getProperty( nk );
+
+            // try global environment..
+            if ( nv == null )
+            {
+                nv = System.getProperty( nk );
+            }
+
+            // if the key cannot be resolved,
+            // leave it alone ( and don't parse again )
+            // else prefix the original string with the
+            // resolved property ( so it can be parsed further )
+            // taking recursion into account.
+            if ( nv == null || nv.equals( k ) )
+            {
+                ret += "${" + nk + "}";
+            }
+            else
+            {
+                v = nv + v;
+            }
+        }
+        return ret + v;
+    }
+}

maven-plugins/maven-resources-plugin/src/main/java/org/apache/maven/plugin/resources/ResourcesMojo.java

@@ -21,12 +21,21 @@ import org.apache.maven.model.Resource;
 import org.apache.maven.plugin.AbstractMojo;
 import org.apache.maven.plugin.MojoExecutionException;
 import org.codehaus.plexus.util.DirectoryScanner;
+import org.codehaus.plexus.util.IOUtil;
+import org.codehaus.plexus.util.InterpolationFilterReader;
 
+import java.io.BufferedReader;
 import java.io.File;
+import java.io.FileReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
+import java.util.Properties;
 import java.util.TreeMap;
 
 /**
@@ -56,6 +65,22 @@ public class ResourcesMojo
      */
     private List resources;
 
+    /**
+     * Wheter to apply filters during transfer.
+     *
+     * @parameter
+     */
+    private boolean filtering = false;
+
+    /**
+     * The name of the filter property file to use.
+     *
+     * @parameter expression="${basedir}/filter.properties"
+     */
+    private File filterPropertiesFile;
+
+    private Properties filterProperties;
+
     private static final String[] EMPTY_STRING_ARRAY = {};
 
     private static final String[] DEFAULT_INCLUDES = {"**/**"};
@@ -63,6 +88,7 @@ public class ResourcesMojo
     public void execute()
         throws MojoExecutionException
     {
+        initializeFiltering();
         copyResources( resources, outputDirectory );
     }
 
@@ -84,7 +110,7 @@ public class ResourcesMojo
                     destinationFile.getParentFile().mkdirs();
                 }
 
-                FileUtils.copyFile( source, destinationFile );
+                copyFile( source, destinationFile );
             }
         }
         catch ( Exception e )
@@ -95,7 +121,6 @@ public class ResourcesMojo
     }
 
     private Map getJarResources( List resources )
-        throws Exception
     {
         Map resourceEntries = new TreeMap();
 
@@ -150,4 +175,51 @@ public class ResourcesMojo
         return resourceEntries;
     }
 
+    private void initializeFiltering()
+        throws MojoExecutionException
+    {
+        if ( filtering )
+        {
+            try
+            {
+                filterProperties = PropertyUtils.loadPropertyFile( filterPropertiesFile, true, true );
+            }
+            catch ( IOException e )
+            {
+                throw new MojoExecutionException( "Error loading property file '" + filterPropertiesFile + "'", e );
+            }
+        }
+    }
+
+    private void copyFile( File from, File to )
+        throws IOException
+    {
+        if ( !filtering )
+        {
+            FileUtils.copyFile( from, to );
+        }
+        else
+        {
+            // buffer so it isn't reading a byte at a time!
+            Reader fileReader = new BufferedReader( new FileReader( from ) );
+            Writer fileWriter = null;
+            try
+            {
+                // support ${token}
+                Reader reader = new InterpolationFilterReader( fileReader, filterProperties, "${", "}" );
+
+                // support @token@
+                reader = new InterpolationFilterReader( reader, filterProperties, "@", "@" );
+
+                fileWriter = new FileWriter( to );
+
+                IOUtil.copy( reader, fileWriter );
+            }
+            finally
+            {
+                IOUtil.close( fileReader );
+                IOUtil.close( fileWriter );
+            }
+        }
+    }
 }