HADOOP-2643 Make migration tool smarter.

git-svn-id: https://svn.apache.org/repos/asf/lucene/hadoop/trunk/src/contrib/hbase@613446 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -201,7 +201,8 @@ Trunk (unreleased changes)
                HMaster shutdown
    HADOOP-2616 hbase not spliting when the total size of region reaches max
                region size * 1.5
-
+   HADOOP-2643 Make migration tool smarter.
+   
 Release 0.15.1
 Branch 0.15
 

src/java/org/apache/hadoop/hbase/HConstants.java

@@ -26,6 +26,14 @@ import org.apache.hadoop.io.Text;
  */
 public interface HConstants {
   
+  // For migration
+
+  /** name of version file */
+  static final String VERSION_FILE_NAME = "hbase.version";
+  
+  /** version of file system */
+  static final String FILE_SYSTEM_VERSION = "0.1";
+  
   // Configuration parameters
   
   // TODO: URL for hbase master like hdfs URLs with host and port.

src/java/org/apache/hadoop/hbase/HMaster.java

@@ -889,6 +889,10 @@ public class HMaster extends Thread implements HConstants, HMasterInterface,
       // Make sure the root directory exists!
       if(! fs.exists(rootdir)) {
         fs.mkdirs(rootdir);
+        FSUtils.setVersion(fs, rootdir);
+      } else if (!FSUtils.checkVersion(fs, rootdir)) {
+        throw new IOException(
+            "file system not correct version. Run hbase.util.Migrate");
       }
 
       if (!fs.exists(rootRegionDir)) {

src/java/org/apache/hadoop/hbase/util/FSUtils.java

@@ -19,12 +19,16 @@
  */
 package org.apache.hadoop.hbase.util;
 
+import java.io.DataInputStream;
 import java.io.IOException;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.fs.FSDataInputStream;
+import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.dfs.DistributedFileSystem;
 
 /**
@@ -71,4 +75,40 @@ public class FSUtils {
     }
     return available;
   }
+  
+  /**
+   * Verifies current version of file system
+   * 
+   * @param fs
+   * @param rootdir
+   * @return true if the current file system is the correct version
+   * @throws IOException
+   */
+  public static boolean checkVersion(FileSystem fs, Path rootdir) throws IOException {
+    Path versionFile = new Path(rootdir, HConstants.VERSION_FILE_NAME);
+    boolean versionOk = false;
+    if (fs.exists(versionFile)) {
+      FSDataInputStream s =
+        fs.open(new Path(rootdir, HConstants.VERSION_FILE_NAME));
+      String version = DataInputStream.readUTF(s);
+      s.close();
+      versionOk = version.compareTo(HConstants.FILE_SYSTEM_VERSION) == 0;
+    }
+    return versionOk;
+  }
+  
+  /**
+   * Sets version of file system
+   * 
+   * @param fs
+   * @param rootdir
+   * @throws IOException
+   */
+  public static void setVersion(FileSystem fs, Path rootdir) throws IOException {
+    FSDataOutputStream s =
+      fs.create(new Path(rootdir, HConstants.VERSION_FILE_NAME));
+    s.writeUTF(HConstants.FILE_SYSTEM_VERSION);
+    s.close();
+  }
+
 }

src/java/org/apache/hadoop/hbase/util/Migrate.java

@@ -136,7 +136,14 @@ public class Migrate extends Configured implements Tool {
     Path rootdir = fs.makeQualified(new Path(          // get path for instance
         conf.get(HConstants.HBASE_DIR, HConstants.DEFAULT_HBASE_DIR)));
 
-    // check for "extra" files
+    // See if there is a file system version file
+    
+    if (FSUtils.checkVersion(fs, rootdir)) {
+      LOG.info("file system is at current level, no upgrade necessary");
+      return 0;
+    }
+    
+    // check for "extra" files and for old upgradable regions
 
     extraFiles(fs, rootdir);
 
@@ -155,10 +162,14 @@ public class Migrate extends Configured implements Tool {
     // scan for left over regions
 
     extraRegions(fs, rootdir);
+    
+    // set file system version
+    
+    FSUtils.setVersion(fs, rootdir);
 
     return 0;
   }
-
+  
   private void extraFiles(FileSystem fs, Path rootdir) throws IOException {
     FileStatus[] stats = fs.listStatus(rootdir);
     if (stats == null || stats.length == 0) {
@@ -175,6 +186,15 @@ public class Migrate extends Configured implements Tool {
           String message = "unrecognized file " + name;
           extraFile(otherFiles, message, fs, stats[i].getPath());
         }
+      } else {
+        String regionName = name.substring(OLD_PREFIX.length());
+        try {
+          Integer.parseInt(regionName);
+          
+        } catch (NumberFormatException e) {
+          extraFile(otherFiles, "old region format can not be converted: " +
+              name, fs, stats[i].getPath());
+        }
       }
     }
   }

src/test/org/apache/hadoop/hbase/MiniHBaseCluster.java

@@ -28,6 +28,8 @@ import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.log4j.Logger;
 
+import org.apache.hadoop.hbase.util.FSUtils;
+
 /**
  * This class creates a single process HBase cluster. One thread is created for
  * each server.
@@ -138,6 +140,7 @@ public class MiniHBaseCluster implements HConstants {
     try {
       this.parentdir = new Path(conf.get(HBASE_DIR, DEFAULT_HBASE_DIR));
       fs.mkdirs(parentdir);
+      FSUtils.setVersion(fs, parentdir);
       this.hbaseCluster = new LocalHBaseCluster(this.conf, nRegionNodes);
       this.hbaseCluster.startup();
     } catch(IOException e) {