From 45a753ccf79d334513c7bc8f2b81c89a4697075d Mon Sep 17 00:00:00 2001
From: Xiaoyu Yao <xyao@apache.org>
Date: Mon, 2 May 2016 19:30:47 -0700
Subject: [PATCH] HDFS-10344. DistributedFileSystem#getTrashRoots should skip
 encryption zone that does not have .Trash. Contributed by Xiaoyu Yao.

---
 .../hadoop/hdfs/DistributedFileSystem.java    |  3 ++
 .../hadoop/hdfs/TestEncryptionZones.java      | 38 +++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java
index a3a8ba043ab..7a562654d46 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java
@@ -2410,6 +2410,9 @@ public Collection<FileStatus> getTrashRoots(boolean allUsers) {
       while (it.hasNext()) {
         Path ezTrashRoot = new Path(it.next().getPath(),
             FileSystem.TRASH_PREFIX);
+        if (!exists(ezTrashRoot)) {
+          continue;
+        }
         if (allUsers) {
           for (FileStatus candidate : listStatus(ezTrashRoot)) {
             if (exists(candidate.getPath())) {
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptionZones.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptionZones.java
index c8d98ee130c..ce2befde759 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptionZones.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestEncryptionZones.java
@@ -28,6 +28,7 @@
 import java.security.PrivilegedExceptionAction;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.List;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CountDownLatch;
@@ -1442,6 +1443,43 @@ public void testRootDirEZTrash() throws Exception {
     verifyShellDeleteWithTrash(shell, encFile);
   }
 
+  @Test(timeout = 120000)
+  public void testGetTrashRoots() throws Exception {
+    final HdfsAdmin dfsAdmin =
+        new HdfsAdmin(FileSystem.getDefaultUri(conf), conf);
+    Path ezRoot1 = new Path("/ez1");
+    fs.mkdirs(ezRoot1);
+    dfsAdmin.createEncryptionZone(ezRoot1, TEST_KEY);
+    Path ezRoot2 = new Path("/ez2");
+    fs.mkdirs(ezRoot2);
+    dfsAdmin.createEncryptionZone(ezRoot2, TEST_KEY);
+    Path ezRoot3 = new Path("/ez3");
+    fs.mkdirs(ezRoot3);
+    dfsAdmin.createEncryptionZone(ezRoot3, TEST_KEY);
+    Collection<FileStatus> trashRootsBegin = fs.getTrashRoots(true);
+    assertEquals("Unexpected getTrashRoots result", 0, trashRootsBegin.size());
+
+    final Path encFile = new Path(ezRoot2, "encFile");
+    final int len = 8192;
+    DFSTestUtil.createFile(fs, encFile, len, (short) 1, 0xFEED);
+    Configuration clientConf = new Configuration(conf);
+    clientConf.setLong(FS_TRASH_INTERVAL_KEY, 1);
+    FsShell shell = new FsShell(clientConf);
+    verifyShellDeleteWithTrash(shell, encFile);
+
+    Collection<FileStatus> trashRootsDelete1 = fs.getTrashRoots(true);
+    assertEquals("Unexpected getTrashRoots result", 1,
+        trashRootsDelete1.size());
+
+    final Path nonEncFile = new Path("/nonEncFile");
+    DFSTestUtil.createFile(fs, nonEncFile, len, (short) 1, 0xFEED);
+    verifyShellDeleteWithTrash(shell, nonEncFile);
+
+    Collection<FileStatus> trashRootsDelete2 = fs.getTrashRoots(true);
+    assertEquals("Unexpected getTrashRoots result", 2,
+        trashRootsDelete2.size());
+  }
+
   private void verifyShellDeleteWithTrash(FsShell shell, Path path)
       throws Exception{
     try {