HDFS-7078. Fix listEZs to work correctly with snapshots. (wang)

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -680,6 +680,8 @@ Release 2.6.0 - UNRELEASED
     HDFS-7075. hadoop-fuse-dfs fails because it cannot find
     JavaKeyStoreProvider$Factory (cmccabe)
 
+    HDFS-7078. Fix listEZs to work correctly with snapshots. (wang)
+
     BREAKDOWN OF HDFS-6134 AND HADOOP-10150 SUBTASKS AND RELATED JIRAS
   
       HDFS-6387. HDFS CLI admin tool for creating & deleting an

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/EncryptionZoneManager.java

@@ -312,7 +312,22 @@ public class EncryptionZoneManager {
 
     int count = 0;
     for (EncryptionZoneInt ezi : tailMap.values()) {
-      zones.add(new EncryptionZone(getFullPathName(ezi),
+      /*
+       Skip EZs that are only present in snapshots. Re-resolve the path to 
+       see if the path's current inode ID matches EZ map's INode ID.
+       
+       INode#getFullPathName simply calls getParent recursively, so will return
+       the INode's parents at the time it was snapshotted. It will not 
+       contain a reference INode.
+      */
+      final String pathName = getFullPathName(ezi);
+      INodesInPath iip = dir.getINodesInPath(pathName, false);
+      INode lastINode = iip.getLastINode();
+      if (lastINode == null || lastINode.getId() != ezi.getINodeId()) {
+        continue;
+      }
+      // Add the EZ to the result list
+      zones.add(new EncryptionZone(pathName,
           ezi.getKeyName(), ezi.getINodeId()));
       count++;
       if (count >= numResponses) {

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptionZones.java

@@ -27,6 +27,7 @@ import java.io.StringReader;
 import java.io.StringWriter;
 import java.net.URI;
 import java.security.PrivilegedExceptionAction;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.Callable;
@@ -1030,6 +1031,9 @@ public class TestEncryptionZones {
    */
   @Test(timeout = 60000)
   public void testSnapshotsOnEncryptionZones() throws Exception {
+    final String TEST_KEY2 = "testkey2";
+    DFSTestUtil.createKey(TEST_KEY2, cluster, conf);
+
     final int len = 8196;
     final Path zoneParent = new Path("/zones");
     final Path zone = new Path(zoneParent, "zone");
@@ -1044,7 +1048,8 @@ public class TestEncryptionZones {
     assertEquals("Got unexpected ez path", zone.toString(),
         dfsAdmin.getEncryptionZoneForPath(snap1Zone).getPath().toString());
 
-    // Now delete the encryption zone, recreate the dir, and take another snapshot
+    // Now delete the encryption zone, recreate the dir, and take another
+    // snapshot
     fsWrapper.delete(zone, true);
     fsWrapper.mkdir(zone, FsPermission.getDirDefault(), true);
     final Path snap2 = fs.createSnapshot(zoneParent);
@@ -1053,11 +1058,35 @@ public class TestEncryptionZones {
         dfsAdmin.getEncryptionZoneForPath(snap2Zone));
 
     // Create the encryption zone again
-    dfsAdmin.createEncryptionZone(zone, TEST_KEY);
+    dfsAdmin.createEncryptionZone(zone, TEST_KEY2);
     final Path snap3 = fs.createSnapshot(zoneParent);
     final Path snap3Zone = new Path(snap3, zone.getName());
+    // Check that snap3's EZ has the correct settings
+    EncryptionZone ezSnap3 = dfsAdmin.getEncryptionZoneForPath(snap3Zone);
     assertEquals("Got unexpected ez path", zone.toString(),
-        dfsAdmin.getEncryptionZoneForPath(snap3Zone).getPath().toString());
+        ezSnap3.getPath().toString());
+    assertEquals("Unexpected ez key", TEST_KEY2, ezSnap3.getKeyName());
+    // Check that older snapshots still have the old EZ settings
+    EncryptionZone ezSnap1 = dfsAdmin.getEncryptionZoneForPath(snap1Zone);
+    assertEquals("Got unexpected ez path", zone.toString(),
+        ezSnap1.getPath().toString());
+    assertEquals("Unexpected ez key", TEST_KEY, ezSnap1.getKeyName());
+
+    // Check that listEZs only shows the current filesystem state
+    ArrayList<EncryptionZone> listZones = Lists.newArrayList();
+    RemoteIterator<EncryptionZone> it = dfsAdmin.listEncryptionZones();
+    while (it.hasNext()) {
+      listZones.add(it.next());
+    }
+    for (EncryptionZone z: listZones) {
+      System.out.println(z);
+    }
+    assertEquals("Did not expect additional encryption zones!", 1,
+        listZones.size());
+    EncryptionZone listZone = listZones.get(0);
+    assertEquals("Got unexpected ez path", zone.toString(),
+        listZone.getPath().toString());
+    assertEquals("Unexpected ez key", TEST_KEY2, listZone.getKeyName());
 
     // Verify contents of the snapshotted file
     final Path snapshottedZoneFile = new Path(
@@ -1065,7 +1094,8 @@ public class TestEncryptionZones {
     assertEquals("Contents of snapshotted file have changed unexpectedly",
         contents, DFSTestUtil.readFile(fs, snapshottedZoneFile));
 
-    // Now delete the snapshots out of order and verify the zones are still correct
+    // Now delete the snapshots out of order and verify the zones are still
+    // correct
     fs.deleteSnapshot(zoneParent, snap2.getName());
     assertEquals("Got unexpected ez path", zone.toString(),
         dfsAdmin.getEncryptionZoneForPath(snap1Zone).getPath().toString());