HBASE-1215 migration; final part. Adds a MR job to rewrite store files.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/hbase/trunk@796890 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/hadoop/hbase/mapreduce/Driver.java

@@ -19,6 +19,7 @@
  */
 package org.apache.hadoop.hbase.mapreduce;
 
+import org.apache.hadoop.hbase.migration.nineteen.HStoreFileToStoreFile;
 import org.apache.hadoop.util.ProgramDriver;
 
 /**
@@ -34,6 +35,9 @@ public class Driver {
     ProgramDriver pgd = new ProgramDriver();
     pgd.addClass(RowCounter.NAME, RowCounter.class,
       "Count rows in HBase table");
+    pgd.addClass(HStoreFileToStoreFile.JOBNAME,
+      HStoreFileToStoreFile.class,
+      "Bulk convert 0.19 HStoreFiles to 0.20 StoreFiles");
     pgd.driver(args);
   }
 }

src/java/org/apache/hadoop/hbase/mapreduce/RowCounter.java

@@ -124,5 +124,4 @@ public class RowCounter {
     Job job = createSubmittableJob(conf, otherArgs);
     System.exit(job.waitForCompletion(true) ? 0 : 1);
   }
-  
 }

src/java/org/apache/hadoop/hbase/migration/nineteen/HStoreFileToStoreFile.java

@@ -0,0 +1,157 @@
+/*
+ * Copyright 2009 The Apache Software Foundation
+ *
+ * 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.migration.nineteen;
+
+import java.io.IOException;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.fs.FSDataOutputStream;
+import org.apache.hadoop.fs.FileStatus;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hbase.HBaseConfiguration;
+import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.util.FSUtils;
+import org.apache.hadoop.hbase.util.Migrate;
+import org.apache.hadoop.hbase.util.FSUtils.DirFilter;
+import org.apache.hadoop.io.LongWritable;
+import org.apache.hadoop.io.Text;
+import org.apache.hadoop.mapreduce.Job;
+import org.apache.hadoop.mapreduce.Mapper;
+import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
+import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
+import org.apache.hadoop.util.GenericOptionsParser;
+
+/**
+ * Mapper that rewrites hbase 0.19 HStoreFiles as 0.20 StoreFiles.
+ * Creates passed directories as input and output.  On startup, it checks
+ * filesystem is 0.19 generation.  It then crawls the filesystem to find the
+ * files to migrate writing a file into the input directory.  Next it starts up
+ * the MR job to rewrite the 0.19 HStoreFiles as 0.20 StoreFiles deleting the
+ * old as it goes.  Presumption is that only
+ * one file per in the family Store else stuff breaks; i.e. the 0.19 install
+ * was major compacted before migration began.
+ */
+public class HStoreFileToStoreFile {
+  static final Log LOG = LogFactory.getLog(HStoreFileToStoreFile.class);
+  public static final String JOBNAME = "hsf2sf";
+
+  public static class Map extends Mapper<LongWritable, Text, LongWritable, LongWritable> {
+    protected void map(LongWritable key, Text value, Mapper<LongWritable,Text, LongWritable, LongWritable>.Context context)
+    throws java.io.IOException, InterruptedException {
+      HBaseConfiguration c = new HBaseConfiguration(context.getConfiguration());
+      Migrate.rewrite(c, FileSystem.get(c), new Path(value.toString()));
+    }
+  }
+
+  private static void writeInputFiles(final HBaseConfiguration conf,
+      final FileSystem fs, final Path dir)
+  throws IOException {
+    if (!FSUtils.isPre020FileLayout(fs, FSUtils.getRootDir(conf))) {
+      throw new IOException("Not a pre-0.20 filesystem");
+    }
+    if (fs.exists(dir)) {
+      throw new IOException("Input exists -- please specify empty input dir");
+    }
+    FSDataOutputStream out = fs.create(new Path(dir, "mapfiles"));
+    try {
+      gathermapfiles(conf, fs, out);
+    } finally {
+      out.close();
+    }
+  }
+  
+  private static void gathermapfiles(final HBaseConfiguration conf,
+      final FileSystem fs, final FSDataOutputStream out)
+  throws IOException {
+    // Presumes any directory under hbase.rootdir is a table.
+    FileStatus [] tableDirs =
+      fs.listStatus(FSUtils.getRootDir(conf), new DirFilter(fs));
+    for (int i = 0; i < tableDirs.length; i++) {
+      // Inside a table, there are compaction.dir directories to skip.
+      // Otherwise, all else should be regions.  Then in each region, should
+      // only be family directories.  Under each of these, should be a mapfile
+      // and info directory and in these only one file.
+      Path d = tableDirs[i].getPath();
+      if (d.getName().equals(HConstants.HREGION_LOGDIR_NAME)) continue;
+      FileStatus [] regionDirs = fs.listStatus(d, new DirFilter(fs));
+      for (int j = 0; j < regionDirs.length; j++) {
+        Path dd = regionDirs[j].getPath();
+        if (dd.equals(HConstants.HREGION_COMPACTIONDIR_NAME)) continue;
+        // Else its a region name.  Now look in region for families.
+        FileStatus [] familyDirs = fs.listStatus(dd, new DirFilter(fs));
+        for (int k = 0; k < familyDirs.length; k++) {
+          Path family = familyDirs[k].getPath();
+          FileStatus [] infoAndMapfile = fs.listStatus(family);
+          // Assert that only info and mapfile in family dir.
+          if (infoAndMapfile.length != 0 && infoAndMapfile.length != 2) {
+            throw new IOException(family.toString() +
+              " has more than just info and mapfile: " + infoAndMapfile.length);
+          }
+          // Make sure directory named info or mapfile.
+          for (int ll = 0; ll < 2; ll++) {
+            if (infoAndMapfile[ll].getPath().getName().equals("info") ||
+                infoAndMapfile[ll].getPath().getName().equals("mapfiles"))
+              continue;
+            throw new IOException("Unexpected directory name: " +
+              infoAndMapfile[ll].getPath());
+          }
+          // Now in family, there are 'mapfile' and 'info' subdirs.  Just
+          // look in the 'mapfile' subdir.
+          FileStatus [] familyStatus =
+            fs.listStatus(new Path(family, "mapfiles"));
+          if (familyStatus.length > 1) {
+            throw new IOException(family.toString() + " has " + familyStatus.length +
+              " files.");
+          }
+          // If we got here, then this is good.  Add the mapfile to out
+          String str = familyStatus[0].getPath().makeQualified(fs).toString();
+          LOG.info(str);
+          out.write(Bytes.toBytes(str + "\n"));
+        }
+      }
+    }
+  }
+
+  public static void main(String[] args) throws Exception {
+    HBaseConfiguration conf = new HBaseConfiguration();
+    String [] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
+    if (otherArgs.length < 2) {
+      System.err.println("ERROR: Wrong number of parameters: " + args.length);
+      System.err.println("Usage: " + HStoreFileToStoreFile.class.getName() + 
+        " <inputdir> <output>");
+      System.exit(-1);
+    }
+    Path input = new Path(args[0]);
+    FileSystem fs = FileSystem.get(conf);
+    writeInputFiles(conf, fs, input);
+    Job job = new Job(conf);
+    job.setJarByClass(HStoreFileToStoreFile.class);
+    job.setJobName(JOBNAME);
+    job.setMapperClass(Map.class);
+    job.setNumReduceTasks(0);
+    FileInputFormat.setInputPaths(job, input);
+    Path output = new Path(args[1]);
+    FileOutputFormat.setOutputPath(job, output);
+    System.exit(job.waitForCompletion(true) ? 0 : 1);
+  }
+}

src/java/org/apache/hadoop/hbase/migration/package-info.java

@@ -19,6 +19,8 @@
  */
 /**
 Provides classes from old hbase versions used migrating data.
-Nineteen package has classes from hbase 0.19.
+Nineteen package has classes from hbase 0.19.  See
+<a href="http://wiki.apache.org/hadoop/Hbase/HowToMigrate">How to Migrate</a>
+for more on migrations.
 */
 package org.apache.hadoop.hbase.migration;