HDFS-8345. Storage policy APIs must be exposed via the FileSystem interface. (Arpit Agarwal)

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

@@ -23,6 +23,7 @@
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.List;
@@ -1221,6 +1222,32 @@ public void deleteSnapshot(final Path snapshotDir, final String snapshotName)
         + " doesn't support deleteSnapshot");
   }
 
+  /**
+   * Set the storage policy for a given file or directory.
+   *
+   * @param path file or directory path.
+   * @param policyName the name of the target storage policy. The list
+   *                   of supported Storage policies can be retrieved
+   *                   via {@link #getAllStoragePolicies}.
+   */
+  public void setStoragePolicy(final Path path, final String policyName)
+      throws IOException {
+    throw new UnsupportedOperationException(getClass().getSimpleName()
+        + " doesn't support setStoragePolicy");
+  }
+
+  /**
+   * Retrieve all the storage policies supported by this file system.
+   *
+   * @return all storage policies supported by this filesystem.
+   * @throws IOException
+   */
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    throw new UnsupportedOperationException(getClass().getSimpleName()
+        + " doesn't support getAllStoragePolicies");
+  }
+
   @Override //Object
   public int hashCode() {
     return myUri.hashCode();

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

@@ -0,0 +1,72 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hadoop.fs;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;
+
+/**
+ * A storage policy specifies the placement of block replicas on specific
+ * storage types.
+ */
+@InterfaceAudience.Public
+@InterfaceStability.Stable
+public interface BlockStoragePolicySpi {
+
+  /**
+   * Return the name of the storage policy. Policies are uniquely
+   * identified by name.
+   *
+   * @return the name of the storage policy.
+   */
+  String getName();
+
+  /**
+   * Return the preferred storage types associated with this policy. These
+   * storage types are used sequentially for successive block replicas.
+   *
+   * @return preferred storage types used for placing block replicas.
+   */
+  StorageType[] getStorageTypes();
+
+  /**
+   * Get the fallback storage types for creating new block replicas. Fallback
+   * storage types are used if the preferred storage types are not available.
+   *
+   * @return fallback storage types for new block replicas..
+   */
+  StorageType[] getCreationFallbacks();
+
+  /**
+   * Get the fallback storage types for replicating existing block replicas.
+   * Fallback storage types are used if the preferred storage types are not
+   * available.
+   *
+   * @return fallback storage types for replicating existing block replicas.
+   */
+  StorageType[] getReplicationFallbacks();
+
+  /**
+   * Returns true if the policy is inherit-only and cannot be changed for
+   * an existing file.
+   *
+   * @return true if the policy is inherit-only.
+   */
+  boolean isCopyOnCreateFile();
+}

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

@@ -24,6 +24,7 @@
 import java.net.URI;
 import java.security.PrivilegedExceptionAction;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.HashSet;
 import java.util.IdentityHashMap;
@@ -2665,4 +2666,36 @@ public Void next(final AbstractFileSystem fs, final Path p)
       }
     }.resolve(this, absF);
   }
+
+  /**
+   * Set the storage policy for a given file or directory.
+   *
+   * @param path file or directory path.
+   * @param policyName the name of the target storage policy. The list
+   *                   of supported Storage policies can be retrieved
+   *                   via {@link #getAllStoragePolicies}.
+   */
+  public void setStoragePolicy(final Path path, final String policyName)
+      throws IOException {
+    final Path absF = fixRelativePart(path);
+    new FSLinkResolver<Void>() {
+      @Override
+      public Void next(final AbstractFileSystem fs, final Path p)
+          throws IOException {
+        fs.setStoragePolicy(path, policyName);
+        return null;
+      }
+    }.resolve(this, absF);
+  }
+
+  /**
+   * Retrieve all the storage policies supported by this file system.
+   *
+   * @return all storage policies supported by this filesystem.
+   * @throws IOException
+   */
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    return defaultFS.getAllStoragePolicies();
+  }
 }

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

@@ -26,6 +26,7 @@
 import java.security.PrivilegedExceptionAction;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -2609,6 +2610,33 @@ public void removeXAttr(Path path, String name) throws IOException {
         + " doesn't support removeXAttr");
   }
 
+  /**
+   * Set the storage policy for a given file or directory.
+   *
+   * @param src file or directory path.
+   * @param policyName the name of the target storage policy. The list
+   *                   of supported Storage policies can be retrieved
+   *                   via {@link #getAllStoragePolicies}.
+   * @throws IOException
+   */
+  public void setStoragePolicy(final Path src, final String policyName)
+      throws IOException {
+    throw new UnsupportedOperationException(getClass().getSimpleName()
+        + " doesn't support setStoragePolicy");
+  }
+
+  /**
+   * Retrieve all the storage policies supported by this file system.
+   *
+   * @return all storage policies supported by this filesystem.
+   * @throws IOException
+   */
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    throw new UnsupportedOperationException(getClass().getSimpleName()
+        + " doesn't support getAllStoragePolicies");
+  }
+
   // making it volatile to be able to do a double checked locking
   private volatile static boolean FILE_SYSTEMS_LOADED = false;
 

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

@@ -21,6 +21,7 @@
 import java.io.*;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Map;
@@ -619,4 +620,16 @@ public List<String> listXAttrs(Path path) throws IOException {
   public void removeXAttr(Path path, String name) throws IOException {
     fs.removeXAttr(path, name);
   }
+
+  @Override
+  public void setStoragePolicy(Path src, String policyName)
+      throws IOException {
+    fs.setStoragePolicy(src, policyName);
+  }
+
+  @Override
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    return fs.getAllStoragePolicies();
+  }
 }

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

@@ -20,6 +20,7 @@
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Map;
@@ -397,4 +398,16 @@ public void deleteSnapshot(final Path path, final String snapshotName)
       throws IOException {
     myFs.deleteSnapshot(path, snapshotName);
   }
+
+  @Override
+  public void setStoragePolicy(Path path, String policyName)
+      throws IOException {
+    myFs.setStoragePolicy(path, policyName);
+  }
+
+  @Override
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    return myFs.getAllStoragePolicies();
+  }
 }

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

@@ -20,6 +20,7 @@
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Map;
@@ -28,6 +29,7 @@
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.fs.AbstractFileSystem;
 import org.apache.hadoop.fs.BlockLocation;
+import org.apache.hadoop.fs.BlockStoragePolicySpi;
 import org.apache.hadoop.fs.CreateFlag;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.FSDataOutputStream;
@@ -377,6 +379,18 @@ public void deleteSnapshot(Path snapshotDir, String snapshotName)
     myFs.deleteSnapshot(fullPath(snapshotDir), snapshotName);
   }
 
+  @Override
+  public void setStoragePolicy(Path path, String policyName)
+    throws IOException {
+    myFs.setStoragePolicy(fullPath(path), policyName);
+  }
+
+  @Override
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    return myFs.getAllStoragePolicies();
+  }
+
   @Override
   public void setVerifyChecksum(final boolean verifyChecksum)
       throws IOException, UnresolvedLinkException {

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

@@ -740,6 +740,14 @@ public void deleteSnapshot(Path path, String snapshotName) throws IOException {
     res.targetFileSystem.deleteSnapshot(res.remainingPath, snapshotName);
   }
 
+  @Override
+  public void setStoragePolicy(final Path path, final String policyName)
+      throws IOException {
+    InodeTree.ResolveResult<AbstractFileSystem> res =
+        fsState.resolve(getUriPath(path), true);
+    res.targetFileSystem.setStoragePolicy(res.remainingPath, policyName);
+  }
+
   /*
    * An instance of this class represents an internal dir of the viewFs 
    * ie internal dir of the mount table.
@@ -1070,5 +1078,11 @@ public void deleteSnapshot(Path path, String snapshotName)
       checkPathIsSlash(path);
       throw readOnlyMountTable("deleteSnapshot", path);
     }
+
+    @Override
+    public void setStoragePolicy(Path path, String policyName)
+        throws IOException {
+      throw readOnlyMountTable("setStoragePolicy", path);
+    }
   }
 }

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

@@ -34,6 +34,7 @@
 import java.io.IOException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.Iterator;
 import java.util.List;
@@ -205,6 +206,12 @@ public Map<String, byte[]> getXAttrs(Path path, List<String> names)
     public AclStatus getAclStatus(Path path) throws IOException;
 
     public void access(Path path, FsAction mode) throws IOException;
+
+    public void setStoragePolicy(Path src, String policyName)
+        throws IOException;
+
+    public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+        throws IOException;
   }
 
   @Test

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/BlockStoragePolicy.java

@@ -25,6 +25,7 @@
 
 import com.google.common.annotations.VisibleForTesting;
 import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.fs.BlockStoragePolicySpi;
 import org.apache.hadoop.fs.StorageType;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -34,7 +35,7 @@
  * for the replicas of a block.
  */
 @InterfaceAudience.Private
-public class BlockStoragePolicy {
+public class BlockStoragePolicy implements BlockStoragePolicySpi {
   public static final Logger LOG = LoggerFactory.getLogger(BlockStoragePolicy
       .class);
 
@@ -239,18 +240,22 @@ public byte getId() {
     return id;
   }
 
+  @Override
   public String getName() {
     return name;
   }
 
+  @Override
   public StorageType[] getStorageTypes() {
     return this.storageTypes;
   }
 
+  @Override
   public StorageType[] getCreationFallbacks() {
     return this.creationFallbacks;
   }
 
+  @Override
   public StorageType[] getReplicationFallbacks() {
     return this.replicationFallbacks;
   }
@@ -265,6 +270,7 @@ private static StorageType getFallback(EnumSet<StorageType> unavailables,
     return null;
   }
 
+  @Override
   public boolean isCopyOnCreateFile() {
     return copyOnCreateFile;
   }

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

@@ -567,6 +567,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-8157. Writes to RAM DISK reserve locked memory for block files.
     (Arpit Agarwal)
 
+    HDFS-8345. Storage policy APIs must be exposed via the FileSystem
+    interface. (Arpit Agarwal)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/fs/Hdfs.java

@@ -22,6 +22,8 @@
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Map;
@@ -465,6 +467,17 @@ public void access(Path path, final FsAction mode) throws IOException {
     dfs.checkAccess(getUriPath(path), mode);
   }
 
+  @Override
+  public void setStoragePolicy(Path path, String policyName) throws IOException {
+    dfs.setStoragePolicy(getUriPath(path), policyName);
+  }
+
+  @Override
+  public Collection<? extends BlockStoragePolicySpi> getAllStoragePolicies()
+      throws IOException {
+    return Arrays.asList(dfs.getStoragePolicies());
+  }
+
   /**
    * Renew an existing delegation token.
    * 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DistributedFileSystem.java

@@ -23,6 +23,8 @@
 import java.net.InetSocketAddress;
 import java.net.URI;
 import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
 import java.util.EnumSet;
 import java.util.List;
 import java.util.Map;
@@ -32,6 +34,7 @@
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.BlockLocation;
 import org.apache.hadoop.fs.BlockStorageLocation;
+import org.apache.hadoop.fs.BlockStoragePolicySpi;
 import org.apache.hadoop.fs.CacheFlag;
 import org.apache.hadoop.fs.ContentSummary;
 import org.apache.hadoop.fs.CreateFlag;
@@ -532,6 +535,7 @@ public Boolean next(final FileSystem fs, final Path p)
    * @param src The source path referring to either a directory or a file.
    * @param policyName The name of the storage policy.
    */
+  @Override
   public void setStoragePolicy(final Path src, final String policyName)
       throws IOException {
     statistics.incrementWriteOps(1);
@@ -546,19 +550,24 @@ public Void doCall(final Path p)
       @Override
       public Void next(final FileSystem fs, final Path p)
           throws IOException {
-        if (fs instanceof DistributedFileSystem) {
-          ((DistributedFileSystem) fs).setStoragePolicy(p, policyName);
-          return null;
-        } else {
-          throw new UnsupportedOperationException(
-              "Cannot perform setStoragePolicy on a non-DistributedFileSystem: "
-                  + src + " -> " + p);
-        }
+        fs.setStoragePolicy(p, policyName);
+        return null;
       }
     }.resolve(this, absF);
   }
 
-  /** Get all the existing storage policies */
+  @Override
+  public Collection<BlockStoragePolicy> getAllStoragePolicies()
+      throws IOException {
+    return Arrays.asList(dfs.getStoragePolicies());
+  }
+
+  /**
+   * Deprecated. Prefer {@link FileSystem#getAllStoragePolicies()}
+   * @return
+   * @throws IOException
+   */
+  @Deprecated
   public BlockStoragePolicy[] getStoragePolicies() throws IOException {
     statistics.incrementReadOps(1);
     return dfs.getStoragePolicies();

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/mover/Mover.java

@@ -27,6 +27,7 @@
 import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.conf.Configured;
+import org.apache.hadoop.fs.BlockStoragePolicySpi;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.fs.StorageType;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
@@ -152,8 +153,8 @@ void init() throws IOException {
   }
 
   private void initStoragePolicies() throws IOException {
-    BlockStoragePolicy[] policies = dispatcher.getDistributedFileSystem()
-        .getStoragePolicies();
+    Collection<BlockStoragePolicy> policies =
+        dispatcher.getDistributedFileSystem().getAllStoragePolicies();
     for (BlockStoragePolicy policy : policies) {
       this.blockStoragePolicies[policy.getId()] = policy;
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/StoragePolicyAdmin.java

@@ -30,6 +30,7 @@
 
 import java.io.IOException;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.LinkedList;
 import java.util.List;
 
@@ -97,7 +98,7 @@ public String getLongUsage() {
     public int run(Configuration conf, List<String> args) throws IOException {
       final DistributedFileSystem dfs = AdminHelper.getDFS(conf);
       try {
-        BlockStoragePolicy[] policies = dfs.getStoragePolicies();
+        Collection<BlockStoragePolicy> policies = dfs.getAllStoragePolicies();
         System.out.println("Block Storage Policies:");
         for (BlockStoragePolicy policy : policies) {
           if (policy != null) {
@@ -155,7 +156,7 @@ public int run(Configuration conf, List<String> args) throws IOException {
           System.out.println("The storage policy of " + path + " is unspecified");
           return 0;
         }
-        BlockStoragePolicy[] policies = dfs.getStoragePolicies();
+        Collection<BlockStoragePolicy> policies = dfs.getAllStoragePolicies();
         for (BlockStoragePolicy p : policies) {
           if (p.getId() == storagePolicyId) {
             System.out.println("The storage policy of " + path + ":\n" + p);

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

@@ -25,7 +25,9 @@
 import java.util.*;
 
 import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.BlockStoragePolicySpi;
 import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
@@ -1150,30 +1152,6 @@ public void testChooseTargetWithTopology() throws Exception {
     Assert.assertEquals(3, targets.length);
   }
 
-  /**
-   * Test getting all the storage policies from the namenode
-   */
-  @Test
-  public void testGetAllStoragePolicies() throws Exception {
-    final MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf)
-        .numDataNodes(0).build();
-    cluster.waitActive();
-    final DistributedFileSystem fs = cluster.getFileSystem();
-    try {
-      BlockStoragePolicy[] policies = fs.getStoragePolicies();
-      Assert.assertEquals(6, policies.length);
-      Assert.assertEquals(POLICY_SUITE.getPolicy(COLD).toString(),
-          policies[0].toString());
-      Assert.assertEquals(POLICY_SUITE.getPolicy(WARM).toString(),
-          policies[1].toString());
-      Assert.assertEquals(POLICY_SUITE.getPolicy(HOT).toString(),
-          policies[2].toString());
-    } finally {
-      IOUtils.cleanup(null, fs);
-      cluster.shutdown();
-    }
-  }
-
   @Test
   public void testGetFileStoragePolicyAfterRestartNN() throws Exception {
     //HDFS8219
@@ -1217,4 +1195,42 @@ public void testGetFileStoragePolicyAfterRestartNN() throws Exception {
       cluster.shutdown();
     }
   }
+
+  /**
+   * Verify that {@link FileSystem#getAllStoragePolicies} returns all
+   * known storage policies for DFS.
+   *
+   * @throws IOException
+   */
+  @Test
+  public void testGetAllStoragePoliciesFromFs() throws IOException {
+    final MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf)
+        .numDataNodes(REPLICATION)
+        .storageTypes(
+            new StorageType[] {StorageType.DISK, StorageType.ARCHIVE})
+        .build();
+    try {
+      cluster.waitActive();
+
+      // Get policies via {@link FileSystem#getAllStoragePolicies}
+      Set<String> policyNamesSet1 = new HashSet<>();
+      for (BlockStoragePolicySpi policy :
+          cluster.getFileSystem().getAllStoragePolicies()) {
+        policyNamesSet1.add(policy.getName());
+      }
+
+      // Get policies from the default BlockStoragePolicySuite.
+      BlockStoragePolicySuite suite = BlockStoragePolicySuite.createDefaultSuite();
+      Set<String> policyNamesSet2 = new HashSet<>();
+      for (BlockStoragePolicy policy : suite.getAllPolicies()) {
+        policyNamesSet2.add(policy.getName());
+      }
+
+      // Ensure that we got the same set of policies in both cases.
+      Assert.assertTrue(Sets.difference(policyNamesSet1, policyNamesSet2).isEmpty());
+      Assert.assertTrue(Sets.difference(policyNamesSet2, policyNamesSet1).isEmpty());
+    } finally {
+      cluster.shutdown();
+    }
+  }
 }