Implemented the rollback() method for the TransactionEvents

git-svn-id: https://svn.apache.org/repos/asf/maven/repository-manager/trunk@412747 13f79535-47bb-0310-9956-ffa450edef68

maven-repository-converter/src/main/java/org/apache/maven/repository/converter/DefaultRepositoryConverter.java

@@ -376,7 +376,6 @@ public class DefaultRepositoryConverter
         boolean result = true;
         if ( file.exists() )
         {
-            // TODO: utility methods in the model converter
             File targetFile = new File( targetRepository.getBasedir(), targetRepository.pathOf( pom ) );
 
             String contents = null;

maven-repository-converter/src/main/java/org/apache/maven/repository/converter/transaction/AbstractTransactionEvent.java

@@ -0,0 +1,120 @@
+package org.apache.maven.repository.converter.transaction;
+
+/*
+ * Copyright 2005-2006 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.FileUtils;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Collections;
+import java.util.List;
+import java.util.ArrayList;
+
+/**
+ * Abstract class for the TransactionEvents
+ *
+ * @author Edwin Punzalan
+ */
+public abstract class AbstractTransactionEvent
+    implements TransactionEvent
+{
+    private File backup;
+
+    private List createdDirs;
+
+    /**
+     * Method that creates a directory as well as all the parent directories needed
+     *
+     * @param dir The File directory to be created
+     * @throws IOException when an unrecoverable error occurred
+     */
+    protected void mkDirs( File dir )
+        throws IOException
+    {
+        List createDirs = new ArrayList();
+
+        File parent = dir;
+        while( !parent.exists() || !parent.isDirectory() )
+        {
+            createDirs.add( parent );
+
+            parent = parent.getParentFile();
+        }
+
+        createdDirs = new ArrayList();
+
+        while ( !createDirs.isEmpty() )
+        {
+            File directory = (File) createDirs.remove( createDirs.size() - 1 );
+
+            if ( directory.mkdir() )
+            {
+                createdDirs.add( directory );
+            }
+            else
+            {
+                throw new IOException( "Failed to create directory: " + directory.getAbsolutePath() );
+            }
+        }
+    }
+
+    protected void revertMkDirs()
+        throws IOException
+    {
+        if ( createdDirs != null )
+        {
+            Collections.reverse( createdDirs );
+
+            while( !createdDirs.isEmpty() )
+            {
+                File dir = (File) createdDirs.remove( 0 );
+
+                if ( dir.isDirectory() && dir.list().length == 0 )
+                {
+                    FileUtils.deleteDirectory( dir.getAbsolutePath() );
+                }
+                else
+                {
+                    //cannot rollback created directory if it still contains files
+                    break;
+                }
+            }
+        }
+    }
+
+    protected void createBackup( File file )
+        throws IOException
+    {
+        if ( file.exists() && file.isFile() )
+        {
+            backup = File.createTempFile( "temp-", ".backup" );
+
+            FileUtils.copyFile( file, backup );
+
+            backup.deleteOnExit();
+        }
+    }
+
+    protected void restoreBackup( File file )
+        throws IOException
+    {
+        if ( backup != null )
+        {
+            FileUtils.copyFile( backup, file );
+        }
+    }
+}

maven-repository-converter/src/main/java/org/apache/maven/repository/converter/transaction/CopyFileEvent.java

@@ -27,7 +27,7 @@ import java.io.IOException;
  * @author <a href="mailto:brett@apache.org">Brett Porter</a>
  */
 public class CopyFileEvent
-    implements TransactionEvent
+    extends AbstractTransactionEvent
 {
     private final File source;
 
@@ -42,7 +42,9 @@ public class CopyFileEvent
     public void commit()
         throws IOException
     {
-        destination.getParentFile().mkdirs();
+        createBackup( destination );
+
+        mkDirs( destination.getParentFile() );
 
         FileUtils.copyFile( source, destination );
     }
@@ -50,6 +52,10 @@ public class CopyFileEvent
     public void rollback()
         throws IOException
     {
-        // TODO: revert to backup/delete if was created
+        FileUtils.fileDelete( destination.getAbsolutePath() );
+
+        revertMkDirs();
+
+        restoreBackup( destination );
     }
 }

maven-repository-converter/src/main/java/org/apache/maven/repository/converter/transaction/CreateFileEvent.java

@@ -27,7 +27,7 @@ import java.io.IOException;
  * @author <a href="mailto:brett@apache.org">Brett Porter</a>
  */
 public class CreateFileEvent
-    implements TransactionEvent
+    extends AbstractTransactionEvent
 {
     private final File destination;
 
@@ -42,7 +42,14 @@ public class CreateFileEvent
     public void commit()
         throws IOException
     {
-        destination.getParentFile().mkdirs();
+        createBackup( destination );
+
+        mkDirs( destination.getParentFile() );
+
+        if ( !destination.exists() && !destination.createNewFile() )
+        {
+            throw new IOException( "Unable to create new file" );
+        }
 
         FileUtils.fileWrite( destination.getAbsolutePath(), content );
     }
@@ -50,6 +57,10 @@ public class CreateFileEvent
     public void rollback()
         throws IOException
     {
-        // TODO: revert to backup/delete if was created
+        FileUtils.fileDelete( destination.getAbsolutePath() );
+
+        revertMkDirs();
+
+        restoreBackup( destination );
     }
 }

maven-repository-converter/src/test/java/org/apache/maven/repository/converter/transaction/CreateFileEventTest.java

@@ -0,0 +1,103 @@
+package org.apache.maven.repository.converter.transaction;
+
+/*
+ * Copyright 2005-2006 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.PlexusTestCase;
+import org.codehaus.plexus.util.FileUtils;
+
+import java.io.File;
+
+/**
+ * @author Edwin Punzalan
+ */
+public class CreateFileEventTest
+    extends PlexusTestCase
+{
+    private File testDir = new File( PlexusTestCase.getBasedir(), "target/transaction-tests/create-file" );
+
+    public void testCreateCommitRollback()
+        throws Exception
+    {
+        File testFile = new File( testDir, "test-file.txt" );
+
+        CreateFileEvent event = new CreateFileEvent( "file contents", testFile );
+
+        assertFalse( "Test file is not yet created", testFile.exists() );
+
+        event.commit();
+
+        assertTrue( "Test file is not yet created", testFile.exists() );
+
+        event.rollback();
+
+        assertFalse( "Test file is has been deleted after rollback", testFile.exists() );
+        assertFalse( "Test file parent directories has been rolledback too", testDir.exists() );
+        assertTrue( "target directory still exists", new File( PlexusTestCase.getBasedir(), "target" ).exists() );
+    }
+
+    public void testCreateCommitRollbackWithBackup()
+        throws Exception
+    {
+        File testFile = new File( testDir, "test-file.txt" );
+
+        testFile.createNewFile();
+
+        FileUtils.fileWrite( testFile.getAbsolutePath(), "original contents" );
+
+        CreateFileEvent event = new CreateFileEvent( "modified contents", testFile );
+
+        String contents = FileUtils.fileRead( testFile.getAbsolutePath() );
+
+        assertEquals( "Test contents have not changed", "original contents", contents );
+
+        event.commit();
+
+        assertTrue( "Test file is not yet created", testFile.exists() );
+
+        event.rollback();
+
+        assertFalse( "Test file is has been deleted after rollback", testFile.exists() );
+        assertFalse( "Test file parent directories has been rolledback too", testDir.exists() );
+        assertTrue( "target directory still exists", new File( PlexusTestCase.getBasedir(), "target" ).exists() );
+    }
+
+    public void testCreateRollbackCommit()
+        throws Exception
+    {
+        File testFile = new File( testDir, "test-file.txt" );
+
+        CreateFileEvent event = new CreateFileEvent( "file contents", testFile );
+
+        assertFalse( "Test file is not yet created", testFile.exists() );
+
+        event.rollback();
+
+        assertFalse( "Test file is not yet created", testFile.exists() );
+
+        event.commit();
+
+        assertTrue( "Test file is not yet created", testFile.exists() );
+    }
+
+    protected void tearDown()
+        throws Exception
+    {
+        super.tearDown();
+
+        FileUtils.deleteDirectory( new File( testDir, "target/transaction-tests" ).getAbsolutePath() );
+    }
+}