HDDS-819. Match OzoneFileSystem behavior with S3AFileSystem. Contributed by Hanisha Koneru.

hadoop-ozone/ozonefs/src/main/java/org/apache/hadoop/fs/ozone/OzoneFileSystem.java

@@ -24,13 +24,17 @@ import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.EnumSet;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.Iterator;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 import com.google.common.base.Preconditions;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 import org.apache.hadoop.hdds.conf.OzoneConfiguration;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -199,17 +203,7 @@ public class OzoneFileSystem extends FileSystem {
         deleteObject(key);
       }
     } catch (FileNotFoundException ignored) {
-      // check if the parent directory needs to be created
-      Path parent = f.getParent();
-      try {
-        // create all the directories for the parent
-        FileStatus parentStatus = getFileStatus(parent);
-        LOG.trace("parent key:{} status:{}", key, parentStatus);
-      } catch (FileNotFoundException e) {
-        mkdirs(parent);
-      }
-      // This exception needs to ignored as this means that the file currently
-      // does not exists and a new file can thus be created.
+      // this means the file is not found
     }
 
     OzoneOutputStream ozoneOutputStream =
@@ -390,8 +384,14 @@ public class OzoneFileSystem extends FileSystem {
     }
   }
 
-  @Override
-  public boolean delete(Path f, boolean recursive) throws IOException {
+  /**
+   * Deletes the children of the input dir path by iterating though the
+   * DeleteIterator.
+   * @param f directory path to be deleted
+   * @return true if successfully deletes all required keys, false otherwise
+   * @throws IOException
+   */
+  private boolean innerDelete(Path f, boolean recursive) throws IOException {
     LOG.trace("delete() path:{} recursive:{}", f, recursive);
     try {
       DeleteIterator iterator = new DeleteIterator(f, recursive);
@@ -402,35 +402,185 @@ public class OzoneFileSystem extends FileSystem {
     }
   }
 
+  @Override
+  public boolean delete(Path f, boolean recursive) throws IOException {
+    LOG.debug("Delete path {} - recursive {}", f, recursive);
+    FileStatus status;
+    try {
+      status = getFileStatus(f);
+    } catch (FileNotFoundException ex) {
+      LOG.warn("delete: Path does not exist: {}", f);
+      return false;
+    }
+
+    String key = pathToKey(f);
+    boolean result;
+
+    if (status.isDirectory()) {
+      LOG.debug("delete: Path is a directory: {}", f);
+      key = addTrailingSlashIfNeeded(key);
+
+      if (key.equals("/")) {
+        LOG.warn("Cannot delete root directory.");
+        return false;
+      }
+
+      result = innerDelete(f, recursive);
+    } else {
+      LOG.debug("delete: Path is a file: {}", f);
+      result = deleteObject(key);
+    }
+
+    if (result) {
+      // If this delete operation removes all files/directories from the
+      // parent direcotry, then an empty parent directory must be created.
+      Path parent = f.getParent();
+      if (parent != null && !parent.isRoot()) {
+        createFakeDirectoryIfNecessary(parent);
+      }
+    }
+
+    return result;
+  }
+
+  /**
+   * Create a fake parent directory key if it does not already exist and no
+   * other child of this parent directory exists.
+   * @param f path to the fake parent directory
+   * @throws IOException
+   */
+  private void createFakeDirectoryIfNecessary(Path f) throws IOException {
+    String key = pathToKey(f);
+    if (!key.isEmpty() && !o3Exists(f)) {
+      LOG.debug("Creating new fake directory at {}", f);
+      String dirKey = addTrailingSlashIfNeeded(key);
+      createDirectory(dirKey);
+    }
+  }
+
+  /**
+   * Check if a file or directory exists corresponding to given path.
+   * @param f path to file/directory.
+   * @return true if it exists, false otherwise.
+   * @throws IOException
+   */
+  private boolean o3Exists(final Path f) throws IOException {
+    Path path = makeQualified(f);
+    try {
+      getFileStatus(path);
+      return true;
+    } catch (FileNotFoundException ex) {
+      return false;
+    }
+  }
+
   private class ListStatusIterator extends OzoneListingIterator {
-    private  List<FileStatus> statuses = new ArrayList<>(LISTING_PAGE_SIZE);
-    private Path f;
+    // _fileStatuses_ maintains a list of file(s) which is either the input
+    // path itself or a child of the input directory path.
+    private List<FileStatus> fileStatuses = new ArrayList<>(LISTING_PAGE_SIZE);
+    // _subDirStatuses_ maintains a list of sub-dirs of the input directory
+    // path.
+    private Map<Path, FileStatus> subDirStatuses =
+        new HashMap<>(LISTING_PAGE_SIZE);
+    private Path f; // the input path
 
     ListStatusIterator(Path f) throws IOException  {
       super(f);
       this.f = f;
     }
 
+    /**
+     * Add the key to the listStatus result if the key corresponds to the
+     * input path or is an immediate child of the input path.
+     * @param key key to be processed
+     * @return always returns true
+     * @throws IOException
+     */
     boolean processKey(String key) throws IOException {
       Path keyPath = new Path(OZONE_URI_DELIMITER + key);
       if (key.equals(getPathKey())) {
         if (pathIsDirectory()) {
+          // if input path is a directory, we add the sub-directories and
+          // files under this directory.
           return true;
         } else {
-          statuses.add(getFileStatus(keyPath));
+          addFileStatus(keyPath);
           return true;
         }
       }
-      // left with only subkeys now
+      // Left with only subkeys now
+      // We add only the immediate child files and sub-dirs i.e. we go only
+      // upto one level down the directory tree structure.
       if (pathToKey(keyPath.getParent()).equals(pathToKey(f))) {
-        // skip keys which are for subdirectories of the directory
-        statuses.add(getFileStatus(keyPath));
+        // This key is an immediate child. Can be file or directory
+        if (key.endsWith(OZONE_URI_DELIMITER)) {
+         // Key is a directory
+          addSubDirStatus(keyPath);
+        } else {
+          addFileStatus(keyPath);
+        }
+      } else {
+        // This key is not the immediate child of the input directory. So we
+        // traverse the parent tree structure of this key until we get the
+        // immediate child of the input directory.
+        Path immediateChildPath = getImmediateChildPath(keyPath.getParent());
+        addSubDirStatus(immediateChildPath);
       }
       return true;
     }
 
+    /**
+     * Adds the FileStatus of keyPath to final result of listStatus.
+     * @param filePath path to the file
+     * @throws FileNotFoundException
+     */
+    void addFileStatus(Path filePath) throws IOException {
+      fileStatuses.add(getFileStatus(filePath));
+    }
+
+    /**
+     * Adds the FileStatus of the subdir to final result of listStatus, if not
+     * already included.
+     * @param dirPath path to the dir
+     * @throws FileNotFoundException
+     */
+    void addSubDirStatus(Path dirPath) throws FileNotFoundException {
+      // Check if subdir path is already included in statuses.
+      if (!subDirStatuses.containsKey(dirPath)) {
+        subDirStatuses.put(dirPath, innerGetFileStatusForDir(dirPath));
+      }
+    }
+
+    /**
+     * Traverse the parent directory structure of keyPath to determine the
+     * which parent/ grand-parent/.. is the immediate child of the input path f.
+     * @param keyPath path whose parent directory structure should be traversed.
+     * @return immediate child path of the input path f.
+     * @return immediate child path of the input path f.
+     */
+    Path getImmediateChildPath(Path keyPath) {
+      Path path = keyPath;
+      Path parent = path.getParent();
+      while (parent != null && !parent.isRoot()) {
+        if (pathToKey(parent).equals(pathToKey(f))) {
+          return path;
+        }
+        path = parent;
+        parent = path.getParent();
+      }
+      return null;
+    }
+
+    /**
+     * Return the result of listStatus operation. If the input path is a
+     * file, return the status for only that file. If the input path is a
+     * directory, return the statuses for all the child files and sub-dirs.
+     */
     FileStatus[] getStatuses() {
-      return statuses.toArray(new FileStatus[statuses.size()]);
+      List<FileStatus> result = Stream.concat(
+          fileStatuses.stream(), subDirStatuses.values().stream())
+          .collect(Collectors.toList());
+      return result.toArray(new FileStatus[result.size()]);
     }
   }
 
@@ -529,28 +679,58 @@ public class OzoneFileSystem extends FileSystem {
           bucket.getCreationTime(), qualifiedPath);
     }
 
-    // consider this a file and get key status
-    OzoneKey meta = getKeyInfo(key);
-    if (meta == null) {
-      key = addTrailingSlashIfNeeded(key);
-      meta = getKeyInfo(key);
+    // Check if the key exists
+    OzoneKey ozoneKey = getKeyInfo(key);
+    if (ozoneKey != null) {
+      LOG.debug("Found exact file for path {}: normal file", f);
+      return new FileStatus(ozoneKey.getDataSize(), false, 1,
+          getDefaultBlockSize(f), ozoneKey.getModificationTime(), 0,
+          FsPermission.getFileDefault(), getUsername(), getUsername(),
+          qualifiedPath);
     }
 
-    if (meta == null) {
-      LOG.trace("File:{} not found", f);
-      throw new FileNotFoundException(f + ": No such file or directory!");
-    } else if (isDirectory(meta)) {
+    return innerGetFileStatusForDir(f);
+  }
+
+  /**
+   * Get the FileStatus for input directory path.
+   * They key corresponding to input path is appended with a trailing slash
+   * to return only the corresponding directory key in the bucket.
+   * @param f directory path
+   * @return FileStatus for the input directory path
+   * @throws FileNotFoundException
+   */
+  public FileStatus innerGetFileStatusForDir(Path f)
+      throws FileNotFoundException {
+    Path qualifiedPath = f.makeQualified(uri, workingDir);
+    String key = pathToKey(qualifiedPath);
+    key = addTrailingSlashIfNeeded(key);
+
+    OzoneKey ozoneKey = getKeyInfo(key);
+    if(ozoneKey != null) {
+      if (isDirectory(ozoneKey)) {
+        // Key is a directory
+        LOG.debug("Found file (with /) for path {}: fake directory", f);
+      } else {
+        // Key is a file with trailing slash
+        LOG.warn("Found file (with /) for path {}: real file? should not " +
+            "happen", f, key);
+      }
       return new FileStatus(0, true, 1, 0,
-          meta.getModificationTime(), 0,
+          ozoneKey.getModificationTime(), 0,
           FsPermission.getDirDefault(), getUsername(), getUsername(),
           qualifiedPath);
-    } else {
-      //TODO: Fetch replication count from ratis config
-      return new FileStatus(meta.getDataSize(), false, 1,
-          getDefaultBlockSize(f), meta.getModificationTime(), 0,
-          FsPermission.getFileDefault(), getUsername(), getUsername(),
-          qualifiedPath);
     }
+
+    // File or directory corresponding to input path does not exist.
+    // Check if there exists a key prefixed with this key.
+    boolean hasChildren = bucket.listKeys(key).hasNext();
+    if (hasChildren) {
+      return new FileStatus(0, true, 1, 0, 0, 0, FsPermission.getDirDefault(),
+          getUsername(), getUsername(), qualifiedPath);
+    }
+
+    throw new FileNotFoundException(f + ": No such file or directory!");
   }
 
   /**
@@ -562,7 +742,7 @@ public class OzoneFileSystem extends FileSystem {
     try {
       return bucket.getKey(key);
     } catch (IOException e) {
-      LOG.trace("Key:{} does not exists", key);
+      LOG.trace("Key:{} does not exist", key);
       return null;
     }
   }
@@ -651,6 +831,13 @@ public class OzoneFileSystem extends FileSystem {
         + "}";
   }
 
+  /**
+   *  This class provides an interface to iterate through all the keys in the
+   *  bucket prefixed with the input path key and process them.
+   *
+   *  Each implementing class should define how the keys should be processed
+   *  through the processKey() function.
+   */
   private abstract class OzoneListingIterator {
     private final Path path;
     private final FileStatus status;
@@ -668,9 +855,23 @@ public class OzoneFileSystem extends FileSystem {
       keyIterator = bucket.listKeys(pathKey);
     }
 
+    /**
+     * The output of processKey determines if further iteration through the
+     * keys should be done or not.
+     * @return true if we should continue iteration of keys, false otherwise.
+     * @throws IOException
+     */
     abstract boolean processKey(String key) throws IOException;
 
-    // iterates all the keys in the particular path
+    /**
+     * Iterates thorugh all the keys prefixed with the input path's key and
+     * processes the key though processKey().
+     * If for any key, the processKey() returns false, then the iteration is
+     * stopped and returned with false indicating that all the keys could not
+     * be processed successfully.
+     * @return true if all keys are processed successfully, false otherwise.
+     * @throws IOException
+     */
     boolean iterate() throws IOException {
       LOG.trace("Iterating path {}", path);
       if (status.isDirectory()) {

hadoop-ozone/ozonefs/src/test/java/org/apache/hadoop/fs/ozone/TestOzoneFileSystem.java

@@ -18,22 +18,192 @@
 
 package org.apache.hadoop.fs.ozone;
 
+import org.apache.commons.io.IOUtils;
+import org.apache.commons.lang3.RandomStringUtils;
+import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
+import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.fs.contract.ContractTestUtils;
+import org.apache.hadoop.hdds.conf.OzoneConfiguration;
+import org.apache.hadoop.hdfs.server.datanode.ObjectStoreHandler;
+import org.apache.hadoop.ozone.MiniOzoneCluster;
 import org.apache.hadoop.ozone.OzoneConsts;
-import org.junit.Assert;
+import org.apache.hadoop.ozone.client.rest.OzoneException;
+import org.apache.hadoop.ozone.web.handlers.BucketArgs;
+import org.apache.hadoop.ozone.web.handlers.KeyArgs;
+import org.apache.hadoop.ozone.web.handlers.UserArgs;
+import org.apache.hadoop.ozone.web.handlers.VolumeArgs;
+import org.apache.hadoop.ozone.web.interfaces.StorageHandler;
+import org.apache.hadoop.ozone.web.response.KeyInfo;
+import org.apache.hadoop.ozone.web.utils.OzoneUtils;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Rule;
 import org.junit.Test;
 
 import java.io.IOException;
+import org.junit.rules.Timeout;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 
 /**
  * Ozone file system tests that are not covered by contract tests.
  */
 public class TestOzoneFileSystem {
 
+  @Rule
+  public Timeout globalTimeout = new Timeout(300_000);
+
+  private static MiniOzoneCluster cluster = null;
+
+  private static FileSystem fs;
+  private static OzoneFileSystem o3fs;
+
+  private static StorageHandler storageHandler;
+  private static UserArgs userArgs;
+  private String volumeName;
+  private String bucketName;
+  private String userName;
+  private String rootPath;
+
+  @Before
+  public void init() throws Exception {
+    OzoneConfiguration conf = new OzoneConfiguration();
+    cluster = MiniOzoneCluster.newBuilder(conf)
+        .setNumDatanodes(3)
+        .build();
+    cluster.waitForClusterToBeReady();
+    storageHandler =
+        new ObjectStoreHandler(conf).getStorageHandler();
+
+    // create a volume and a bucket to be used by OzoneFileSystem
+    userName = "user" + RandomStringUtils.randomNumeric(5);
+    String adminName = "admin" + RandomStringUtils.randomNumeric(5);
+    volumeName = "volume" + RandomStringUtils.randomNumeric(5);
+    bucketName = "bucket" + RandomStringUtils.randomNumeric(5);
+    userArgs = new UserArgs(null, OzoneUtils.getRequestID(),
+        null, null, null, null);
+    VolumeArgs volumeArgs = new VolumeArgs(volumeName, userArgs);
+    volumeArgs.setUserName(userName);
+    volumeArgs.setAdminName(adminName);
+    storageHandler.createVolume(volumeArgs);
+    BucketArgs bucketArgs = new BucketArgs(volumeName, bucketName, userArgs);
+    storageHandler.createBucket(bucketArgs);
+
+    rootPath = String.format("%s://%s.%s/",
+        OzoneConsts.OZONE_URI_SCHEME, bucketName, volumeName);
+
+    // Set the fs.defaultFS and start the filesystem
+    conf.set(CommonConfigurationKeysPublic.FS_DEFAULT_NAME_KEY, rootPath);
+    fs = FileSystem.get(conf);
+    o3fs = (OzoneFileSystem) fs;
+  }
+
+  @After
+  public void teardown() throws IOException {
+    if (cluster != null) {
+      cluster.shutdown();
+    }
+    IOUtils.closeQuietly(fs);
+    IOUtils.closeQuietly(storageHandler);
+  }
+
   @Test
   public void testOzoneFsServiceLoader() throws IOException {
-    Assert.assertEquals(
+    assertEquals(
         FileSystem.getFileSystemClass(OzoneConsts.OZONE_URI_SCHEME, null),
         OzoneFileSystem.class);
   }
+
+  @Test
+  public void testCreateDoesNotAddParentDirKeys() throws Exception {
+    Path grandparent = new Path("/testCreateDoesNotAddParentDirKeys");
+    Path parent = new Path(grandparent, "parent");
+    Path child = new Path(parent, "child");
+    ContractTestUtils.touch(fs, child);
+
+    KeyInfo key = getKey(child, false);
+    assertEquals(key.getKeyName(), o3fs.pathToKey(child));
+
+    // Creating a child should not add parent keys to the bucket
+    try {
+      getKey(parent, true);
+    } catch (IOException ex) {
+      assertKeyNotFoundException(ex);
+    }
+
+    // List status on the parent should show the child file
+    assertEquals("List status of parent should include the 1 child file", 1L,
+        (long)fs.listStatus(parent).length);
+    assertTrue("Parent directory does not appear to be a directory",
+        fs.getFileStatus(parent).isDirectory());
+  }
+
+  @Test
+  public void testDeleteCreatesFakeParentDir() throws Exception {
+    Path grandparent = new Path("/testDeleteCreatesFakeParentDir");
+    Path parent = new Path(grandparent, "parent");
+    Path child = new Path(parent, "child");
+    ContractTestUtils.touch(fs, child);
+
+    // Verify that parent dir key does not exist
+    // Creating a child should not add parent keys to the bucket
+    try {
+      getKey(parent, true);
+    } catch (IOException ex) {
+      assertKeyNotFoundException(ex);
+    }
+
+    // Delete the child key
+    fs.delete(child, false);
+
+    // Deleting the only child should create the parent dir key if it does
+    // not exist
+    String parentKey = o3fs.pathToKey(parent) + "/";
+    KeyInfo parentKeyInfo = getKey(parent, true);
+    assertEquals(parentKey, parentKeyInfo.getKeyName());
+  }
+
+  @Test
+  public void testListStatus() throws Exception {
+    Path parent = new Path("/testListStatus");
+    Path file1 = new Path(parent, "key1");
+    Path file2 = new Path(parent, "key1/key2");
+    ContractTestUtils.touch(fs, file1);
+    ContractTestUtils.touch(fs, file2);
+
+
+    // ListStatus on a directory should return all subdirs along with
+    // files, even if there exists a file and sub-dir with the same name.
+    FileStatus[] fileStatuses = o3fs.listStatus(parent);
+    assertEquals("FileStatus did not return all children of the directory",
+        2, fileStatuses.length);
+
+    // ListStatus should return only the immediate children of a directory.
+    Path file3 = new Path(parent, "dir1/key3");
+    Path file4 = new Path(parent, "dir1/key4");
+    ContractTestUtils.touch(fs, file3);
+    ContractTestUtils.touch(fs, file4);
+    fileStatuses = o3fs.listStatus(parent);
+    assertEquals("FileStatus did not return all children of the directory",
+        3, fileStatuses.length);
+  }
+
+  private KeyInfo getKey(Path keyPath, boolean isDirectory)
+      throws IOException, OzoneException {
+    String key = o3fs.pathToKey(keyPath);
+    if (isDirectory) {
+      key = key + "/";
+    }
+    KeyArgs parentKeyArgs = new KeyArgs(volumeName, bucketName, key,
+        userArgs);
+    return storageHandler.getKeyInfo(parentKeyArgs);
+  }
+
+  private void assertKeyNotFoundException(IOException ex) {
+    GenericTestUtils.assertExceptionContains("KEY_NOT_FOUND", ex);
+  }
 }