svn merge -c 1390616 to fix HADOOP-8843. Old trash directories are never deleted on upgrade from 1.x. Contributed by Jason Lowe

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1390621 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -747,6 +747,9 @@ Release 0.23.4 - UNRELEASED
 
   BUG FIXES
 
+    HADOOP-8843. Old trash directories are never deleted on upgrade
+    from 1.x (jlowe)
+
 Release 0.23.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/TrashPolicyDefault.java

@@ -61,6 +61,9 @@ public class TrashPolicyDefault extends TrashPolicy {
     new FsPermission(FsAction.ALL, FsAction.NONE, FsAction.NONE);
 
   private static final DateFormat CHECKPOINT = new SimpleDateFormat("yyMMddHHmmss");
+  /** Format of checkpoint directories used prior to Hadoop 0.23. */
+  private static final DateFormat OLD_CHECKPOINT =
+      new SimpleDateFormat("yyMMddHHmm");
   private static final int MSECS_PER_MINUTE = 60*1000;
 
   private Path current;
@@ -202,9 +205,7 @@ public class TrashPolicyDefault extends TrashPolicy {
 
       long time;
       try {
-        synchronized (CHECKPOINT) {
+        time = getTimeFromCheckpoint(name);
-          time = CHECKPOINT.parse(name).getTime();
-        }
       } catch (ParseException e) {
         LOG.warn("Unexpected item in trash: "+dir+". Ignoring.");
         continue;
@@ -304,4 +305,22 @@ public class TrashPolicyDefault extends TrashPolicy {
       return (time / interval) * interval;
     }
   }
+
+  private long getTimeFromCheckpoint(String name) throws ParseException {
+    long time;
+
+    try {
+      synchronized (CHECKPOINT) {
+        time = CHECKPOINT.parse(name).getTime();
+      }
+    } catch (ParseException pe) {
+      // Check for old-style checkpoint directories left over
+      // after an upgrade from Hadoop 1.x
+      synchronized (OLD_CHECKPOINT) {
+        time = OLD_CHECKPOINT.parse(name).getTime();
+      }
+    }
+
+    return time;
+  }
 }

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestTrash.java

@@ -26,6 +26,8 @@ import java.io.File;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.net.URI;
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
 import java.util.HashSet;
 import java.util.Set;
 
@@ -434,6 +436,36 @@ public class TestTrash extends TestCase {
           output.indexOf("Failed to determine server trash configuration") != -1);
     }
 
+    // Verify old checkpoint format is recognized
+    {
+      // emulate two old trash checkpoint directories, one that is old enough
+      // to be deleted on the next expunge and one that isn't.
+      long trashInterval = conf.getLong(FS_TRASH_INTERVAL_KEY,
+          FS_TRASH_INTERVAL_DEFAULT);
+      long now = Time.now();
+      DateFormat oldCheckpointFormat = new SimpleDateFormat("yyMMddHHmm");
+      Path dirToDelete = new Path(trashRoot.getParent(),
+          oldCheckpointFormat.format(now - (trashInterval * 60 * 1000) - 1));
+      Path dirToKeep = new Path(trashRoot.getParent(),
+          oldCheckpointFormat.format(now));
+      mkdir(trashRootFs, dirToDelete);
+      mkdir(trashRootFs, dirToKeep);
+
+      // Clear out trash
+      int rc = -1;
+      try {
+        rc = shell.run(new String [] { "-expunge" } );
+      } catch (Exception e) {
+        System.err.println("Exception raised from fs expunge " +
+            e.getLocalizedMessage());
+      }
+      assertEquals(0, rc);
+      assertFalse("old checkpoint format not recognized",
+          trashRootFs.exists(dirToDelete));
+      assertTrue("old checkpoint format directory should not be removed",
+          trashRootFs.exists(dirToKeep));
+    }
+
   }
 
   public static void trashNonDefaultFS(Configuration conf) throws IOException {