| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| package org.apache.hadoop.hbase.master.cleaner; |
| |
| import java.io.IOException; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.fs.FileStatus; |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.fs.Path; |
| import org.apache.hadoop.hbase.HBaseInterfaceAudience; |
| import org.apache.hadoop.hbase.HConstants; |
| import org.apache.hadoop.hbase.classification.InterfaceAudience; |
| import org.apache.hadoop.hbase.io.HFileLink; |
| import org.apache.hadoop.hbase.mob.MobUtils; |
| import org.apache.hadoop.hbase.util.FSUtils; |
| |
| /** |
| * HFileLink cleaner that determines if a hfile should be deleted. |
| * HFiles can be deleted only if there're no links to them. |
| * |
| * When a HFileLink is created a back reference file is created in: |
| * /hbase/archive/table/region/cf/.links-hfile/ref-region.ref-table |
| * To check if the hfile can be deleted the back references folder must be empty. |
| */ |
| @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG) |
| public class HFileLinkCleaner extends BaseHFileCleanerDelegate { |
| private static final Log LOG = LogFactory.getLog(HFileLinkCleaner.class); |
| |
| private FileSystem fs = null; |
| |
| @Override |
| public synchronized boolean isFileDeletable(FileStatus fStat) { |
| if (this.fs == null) return false; |
| Path filePath = fStat.getPath(); |
| // HFile Link is always deletable |
| if (HFileLink.isHFileLink(filePath)) return true; |
| |
| // If the file is inside a link references directory, means that it is a back ref link. |
| // The back ref can be deleted only if the referenced file doesn't exists. |
| Path parentDir = filePath.getParent(); |
| if (HFileLink.isBackReferencesDir(parentDir)) { |
| Path hfilePath = null; |
| try { |
| // Also check if the HFile is in the HBASE_TEMP_DIRECTORY; this is where the referenced |
| // file gets created when cloning a snapshot. |
| hfilePath = HFileLink.getHFileFromBackReference( |
| new Path(FSUtils.getRootDir(getConf()), HConstants.HBASE_TEMP_DIRECTORY), filePath); |
| if (fs.exists(hfilePath)) { |
| return false; |
| } |
| // check whether the HFileLink still exists in mob dir. |
| hfilePath = HFileLink.getHFileFromBackReference(MobUtils.getMobHome(getConf()), filePath); |
| if (fs.exists(hfilePath)) { |
| return false; |
| } |
| hfilePath = HFileLink.getHFileFromBackReference(FSUtils.getRootDir(getConf()), filePath); |
| return !fs.exists(hfilePath); |
| } catch (IOException e) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Couldn't verify if the referenced file still exists, keep it just in case: " |
| + hfilePath); |
| } |
| return false; |
| } |
| } |
| |
| // HFile is deletable only if has no links |
| Path backRefDir = null; |
| try { |
| backRefDir = HFileLink.getBackReferencesDir(parentDir, filePath.getName()); |
| return FSUtils.listStatus(fs, backRefDir) == null; |
| } catch (IOException e) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Couldn't get the references, not deleting file, just in case. filePath=" |
| + filePath + ", backRefDir=" + backRefDir); |
| } |
| return false; |
| } |
| } |
| |
| @Override |
| public synchronized void setConf(Configuration conf) { |
| super.setConf(conf); |
| |
| // setup filesystem |
| try { |
| this.fs = FileSystem.get(this.getConf()); |
| } catch (IOException e) { |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("Couldn't instantiate the file system, not deleting file, just in case. " |
| + FileSystem.FS_DEFAULT_NAME_KEY + "=" |
| + getConf().get(FileSystem.FS_DEFAULT_NAME_KEY, FileSystem.DEFAULT_FS)); |
| } |
| } |
| } |
| } |