hdfs data segment killer

implement hdfs data segment killer

hdfs-storage/src/main/java/io/druid/storage/hdfs/HdfsDataSegmentKiller.java

@@ -0,0 +1,76 @@
+/*
+ * Druid - a distributed column store.
+ * Copyright (C) 2012, 2013  Metamarkets Group Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+package io.druid.storage.hdfs;
+
+import com.google.inject.Inject;
+import io.druid.segment.loading.DataSegmentKiller;
+import io.druid.segment.loading.SegmentLoadingException;
+import io.druid.timeline.DataSegment;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+
+import java.io.IOException;
+
+public class HdfsDataSegmentKiller implements DataSegmentKiller
+{
+  private final Configuration config;
+
+  @Inject
+  public HdfsDataSegmentKiller(final Configuration config)
+  {
+    this.config = config;
+  }
+
+  @Override
+  public void kill(DataSegment segment) throws SegmentLoadingException
+  {
+    final Path path = getPath(segment);
+    final FileSystem fs = checkPathAndGetFilesystem(path);
+    try {
+      fs.delete(path, true);
+    }
+    catch (IOException e) {
+      throw new SegmentLoadingException(e, "Unable to kill segment");
+    }
+  }
+
+  private Path getPath(DataSegment segment)
+  {
+    return new Path(String.valueOf(segment.getLoadSpec().get("path")));
+  }
+
+  private FileSystem checkPathAndGetFilesystem(Path path) throws SegmentLoadingException
+  {
+    FileSystem fs;
+    try {
+      fs = path.getFileSystem(config);
+
+      if (!fs.exists(path)) {
+        throw new SegmentLoadingException("Path[%s] doesn't exist.", path);
+      }
+
+      return fs;
+    }
+    catch (IOException e) {
+      throw new SegmentLoadingException(e, "Problems interacting with filesystem[%s].", path);
+    }
+  }
+}

hdfs-storage/src/main/java/io/druid/storage/hdfs/HdfsStorageDruidModule.java

@@ -55,6 +55,7 @@ public class HdfsStorageDruidModule implements DruidModule
   {
     Binders.dataSegmentPullerBinder(binder).addBinding("hdfs").to(HdfsDataSegmentPuller.class).in(LazySingleton.class);
     Binders.dataSegmentPusherBinder(binder).addBinding("hdfs").to(HdfsDataSegmentPusher.class).in(LazySingleton.class);
+    Binders.dataSegmentKillerBinder(binder).addBinding("hdfs").to(HdfsDataSegmentKiller.class).in(LazySingleton.class);
 
     final Configuration conf = new Configuration();
     if (props != null) {