HDFS-8122. Erasure Coding: Support specifying ECSchema during creation of ECZone. Contributed by Vinayakumar B.

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

@@ -1333,7 +1333,7 @@ public class DFSClient implements java.io.Closeable, RemotePeerFactory,
                              Progressable progress,
                              int buffersize,
                              ChecksumOpt checksumOpt) throws IOException {
-    return create(src, permission, flag, createParent, replication, blockSize, 
+    return create(src, permission, flag, createParent, replication, blockSize,
         progress, buffersize, checksumOpt, null);
   }
 
@@ -3010,12 +3010,12 @@ public class DFSClient implements java.io.Closeable, RemotePeerFactory,
     return new EncryptionZoneIterator(namenode, traceSampler);
   }
 
-  public void createErasureCodingZone(String src)
+  public void createErasureCodingZone(String src, ECSchema schema)
       throws IOException {
     checkOpen();
     TraceScope scope = getPathTraceScope("createErasureCodingZone", src);
     try {
-      namenode.createErasureCodingZone(src);
+      namenode.createErasureCodingZone(src, schema);
     } catch (RemoteException re) {
       throw re.unwrapRemoteException(AccessControlException.class,
           SafeModeException.class,

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

@@ -89,6 +89,7 @@ import org.apache.hadoop.hdfs.security.token.block.InvalidBlockTokenException;
 import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.io.Text;
+import org.apache.hadoop.io.erasurecode.ECSchema;
 import org.apache.hadoop.net.NetUtils;
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.Credentials;
@@ -2273,4 +2274,36 @@ public class DistributedFileSystem extends FileSystem {
       throws IOException {
     return dfs.getInotifyEventStream(lastReadTxid);
   }
+
+  /**
+   * Create the erasurecoding zone
+   * 
+   * @param path Directory to create the ec zone
+   * @param schema ECSchema for the zone. If not specified default will be used.
+   * @throws IOException
+   */
+  public void createErasureCodingZone(final Path path, final ECSchema schema)
+      throws IOException {
+    Path absF = fixRelativePart(path);
+    new FileSystemLinkResolver<Void>() {
+      @Override
+      public Void doCall(final Path p) throws IOException,
+          UnresolvedLinkException {
+        dfs.createErasureCodingZone(getPathName(p), null);
+        return null;
+      }
+
+      @Override
+      public Void next(final FileSystem fs, final Path p) throws IOException {
+        if (fs instanceof DistributedFileSystem) {
+          DistributedFileSystem myDfs = (DistributedFileSystem) fs;
+          myDfs.createErasureCodingZone(p, schema);
+          return null;
+        }
+        throw new UnsupportedOperationException(
+            "Cannot createErasureCodingZone through a symlink to a "
+                + "non-DistributedFileSystem: " + path + " -> " + p);
+      }
+    }.resolve(this, absF);
+  }
 }

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

@@ -1364,11 +1364,11 @@ public interface ClientProtocol {
       long prevId) throws IOException;
 
   /**
-   * Create an erasure coding zone (currently with hardcoded schema)
+   * Create an erasure coding zone with specified schema, if any, otherwise
-   * TODO: Configurable and pluggable schemas (HDFS-7337)
+   * default
    */
   @Idempotent
-  public void createErasureCodingZone(String src)
+  public void createErasureCodingZone(String src, ECSchema schema)
       throws IOException;
 
   /**

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/ClientNamenodeProtocolServerSideTranslatorPB.java

@@ -1403,7 +1403,9 @@ public class ClientNamenodeProtocolServerSideTranslatorPB implements
       RpcController controller, CreateErasureCodingZoneRequestProto req)
       throws ServiceException {
     try {
-      server.createErasureCodingZone(req.getSrc());
+      ECSchema schema = req.hasSchema() ? PBHelper.convertECSchema(req
+          .getSchema()) : null;
+      server.createErasureCodingZone(req.getSrc(), schema);
       return CreateErasureCodingZoneResponseProto.newBuilder().build();
     } catch (IOException e) {
       throw new ServiceException(e);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocolPB/ClientNamenodeProtocolTranslatorPB.java

@@ -1420,11 +1420,14 @@ public class ClientNamenodeProtocolTranslatorPB implements
   }
 
   @Override
-  public void createErasureCodingZone(String src)
+  public void createErasureCodingZone(String src, ECSchema schema)
       throws IOException {
     final CreateErasureCodingZoneRequestProto.Builder builder =
         CreateErasureCodingZoneRequestProto.newBuilder();
     builder.setSrc(src);
+    if (schema != null) {
+      builder.setSchema(PBHelper.convertECSchema(schema));
+    }
     CreateErasureCodingZoneRequestProto req = builder.build();
     try {
       rpcProxy.createErasureCodingZone(null, req);

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

@@ -22,6 +22,9 @@ import com.google.common.collect.Lists;
 import org.apache.hadoop.fs.XAttr;
 import org.apache.hadoop.fs.XAttrSetFlag;
 import org.apache.hadoop.hdfs.XAttrHelper;
+import org.apache.hadoop.hdfs.protocol.proto.HdfsProtos.ECSchemaProto;
+import org.apache.hadoop.hdfs.protocolPB.PBHelper;
+import org.apache.hadoop.io.erasurecode.ECSchema;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -50,7 +53,11 @@ public class ErasureCodingZoneManager {
     this.dir = dir;
   }
 
-  boolean getECPolicy(INodesInPath iip) {
+  boolean getECPolicy(INodesInPath iip) throws IOException {
+    return getECSchema(iip) != null;
+  }
+
+  ECSchema getECSchema(INodesInPath iip) throws IOException{
     assert dir.hasReadLock();
     Preconditions.checkNotNull(iip);
     List<INode> inodes = iip.getReadOnlyINodes();
@@ -64,21 +71,23 @@ public class ErasureCodingZoneManager {
       // EC
       // TODO: properly support symlinks in EC zones
       if (inode.isSymlink()) {
-        return false;
+        return null;
       }
       final List<XAttr> xAttrs = inode.getXAttrFeature() == null ?
           new ArrayList<XAttr>(0)
           : inode.getXAttrFeature().getXAttrs();
       for (XAttr xAttr : xAttrs) {
         if (XATTR_ERASURECODING_ZONE.equals(XAttrHelper.getPrefixName(xAttr))) {
-          return true;
+          ECSchemaProto ecSchemaProto;
+          ecSchemaProto = ECSchemaProto.parseFrom(xAttr.getValue());
+          return PBHelper.convertECSchema(ecSchemaProto);
         }
       }
     }
-    return false;
+    return null;
   }
 
-  XAttr createErasureCodingZone(String src)
+  XAttr createErasureCodingZone(String src, ECSchema schema)
       throws IOException {
     assert dir.hasWriteLock();
     final INodesInPath srcIIP = dir.getINodesInPath4Write(src, false);
@@ -97,8 +106,15 @@ public class ErasureCodingZoneManager {
       throw new IOException("Directory " + src + " is already in an " +
           "erasure coding zone.");
     }
-    final XAttr ecXAttr = XAttrHelper
+    // TODO HDFS-7859 Need to persist the schema in xattr in efficient way
-        .buildXAttr(XATTR_ERASURECODING_ZONE, null);
+    // As of now storing the protobuf format
+    if (schema == null) {
+      schema = ECSchemaManager.getSystemDefaultSchema();
+    }
+    ECSchemaProto schemaProto = PBHelper.convertECSchema(schema);
+    byte[] schemaBytes = schemaProto.toByteArray();
+    final XAttr ecXAttr = XAttrHelper.buildXAttr(XATTR_ERASURECODING_ZONE,
+        schemaBytes);
     final List<XAttr> xattrs = Lists.newArrayListWithCapacity(1);
     xattrs.add(ecXAttr);
     FSDirXAttrOp.unprotectedSetXAttrs(dir, src, xattrs,

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

@@ -59,6 +59,7 @@ import org.apache.hadoop.hdfs.server.common.HdfsServerConstants;
 import org.apache.hadoop.hdfs.server.namenode.INode.BlocksMapUpdateInfo;
 import org.apache.hadoop.hdfs.util.ByteArray;
 import org.apache.hadoop.hdfs.util.EnumCounters;
+import org.apache.hadoop.io.erasurecode.ECSchema;
 import org.apache.hadoop.security.AccessControlException;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.slf4j.Logger;
@@ -388,7 +389,7 @@ public class FSDirectory implements Closeable {
   void disableQuotaChecks() {
     skipQuotaCheck = true;
   }
-
+  
   /**
    * This is a wrapper for resolvePath(). If the path passed
    * is prefixed with /.reserved/raw, then it checks to ensure that the caller
@@ -1225,20 +1226,24 @@ public class FSDirectory implements Closeable {
     }
   }
 
-  XAttr createErasureCodingZone(String src)
+  XAttr createErasureCodingZone(String src, ECSchema schema)
       throws IOException {
     writeLock();
     try {
-      return ecZoneManager.createErasureCodingZone(src);
+      return ecZoneManager.createErasureCodingZone(src, schema);
     } finally {
       writeUnlock();
     }
   }
 
-  public boolean getECPolicy(INodesInPath iip) {
+  public boolean getECPolicy(INodesInPath iip) throws IOException {
+    return getECSchema(iip) != null;
+  }
+
+  ECSchema getECSchema(INodesInPath iip) throws IOException {
     readLock();
     try {
-      return ecZoneManager.getECPolicy(iip);
+      return ecZoneManager.getECSchema(iip);
     } finally {
       readUnlock();
     }

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

@@ -7518,16 +7518,16 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
 
   /**
    * Create an erasure coding zone on directory src.
-   *
+   * @param schema  ECSchema for the erasure coding zone
    * @param src     the path of a directory which will be the root of the
    *                erasure coding zone. The directory must be empty.
+   *
    * @throws AccessControlException  if the caller is not the superuser.
    * @throws UnresolvedLinkException if the path can't be resolved.
    * @throws SafeModeException       if the Namenode is in safe mode.
    */
-  void createErasureCodingZone(final String srcArg,
+  void createErasureCodingZone(final String srcArg, final ECSchema schema,
-      final boolean logRetryCache)
+      final boolean logRetryCache) throws IOException, UnresolvedLinkException,
-      throws IOException, UnresolvedLinkException,
       SafeModeException, AccessControlException {
     String src = srcArg;
     HdfsFileStatus resultingStat = null;
@@ -7543,7 +7543,7 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       checkNameNodeSafeMode("Cannot create erasure coding zone on " + src);
       src = dir.resolvePath(pc, src, pathComponents);
 
-      final XAttr ecXAttr = dir.createErasureCodingZone(src);
+      final XAttr ecXAttr = dir.createErasureCodingZone(src, schema);
       List<XAttr> xAttrs = Lists.newArrayListWithCapacity(1);
       xAttrs.add(ecXAttr);
       getEditLog().logSetXAttrs(src, xAttrs, logRetryCache);
@@ -7573,11 +7573,10 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
       if (isPermissionEnabled) {
         dir.checkPathAccess(pc, iip, FsAction.READ);
       }
-      if (dir.getECPolicy(iip)) {
+      // Get schema set for the zone
-        // TODO HDFS-8074 and HDFS-7859 : To get from loaded schemas
+      ECSchema schema = dir.getECSchema(iip);
-        Map<String, String> options = new HashMap<String, String>();
+      if (schema != null) {
-        ECSchema defaultSchema = new ECSchema("RS-6-3", "rs", 6, 3, options);
+        return new ECInfo(src, schema);
-        return new ECInfo(src, defaultSchema);
       }
     } finally {
       readUnlock();

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

@@ -1823,8 +1823,8 @@ class NameNodeRpcServer implements NamenodeProtocols {
   }
 
   @Override // ClientProtocol
-  public void createErasureCodingZone(String src)
+  public void createErasureCodingZone(String src, ECSchema schema)
-    throws IOException {
+      throws IOException {
     checkNNStartup();
     final CacheEntry cacheEntry = RetryCache.waitForCompletion(retryCache);
     if (cacheEntry != null && cacheEntry.isSuccess()) {
@@ -1832,7 +1832,7 @@ class NameNodeRpcServer implements NamenodeProtocols {
     }
     boolean success = false;
     try {
-      namesystem.createErasureCodingZone(src, cacheEntry != null);
+      namesystem.createErasureCodingZone(src, schema, cacheEntry != null);
     } finally {
       RetryCache.setState(cacheEntry, success);
     }

hadoop-hdfs-project/hadoop-hdfs/src/main/proto/ClientNamenodeProtocol.proto

@@ -716,6 +716,7 @@ message GetEditsFromTxidResponseProto {
 
 message CreateErasureCodingZoneRequestProto {
   required string src = 1;
+  optional ECSchemaProto schema = 2;
 }
 
 message CreateErasureCodingZoneResponseProto {

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

@@ -1855,7 +1855,7 @@ public class DFSTestUtil {
       int numBlocks, int numStripesPerBlk) throws Exception {
     DistributedFileSystem dfs = cluster.getFileSystem();
     dfs.mkdirs(dir);
-    dfs.getClient().createErasureCodingZone(dir.toString());
+    dfs.getClient().createErasureCodingZone(dir.toString(), null);
 
     FSDataOutputStream out = null;
     try {

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

@@ -50,7 +50,7 @@ public class TestDFSStripedOutputStream {
     Configuration conf = new Configuration();
     conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, cellsInBlock * cellSize);
     cluster = new MiniDFSCluster.Builder(conf).numDataNodes(numDNs).build();
-    cluster.getFileSystem().getClient().createErasureCodingZone("/");
+    cluster.getFileSystem().getClient().createErasureCodingZone("/", null);
     fs = cluster.getFileSystem();
   }
 

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

@@ -64,7 +64,7 @@ public class TestErasureCodingZones {
     fs.mkdir(testDir, FsPermission.getDirDefault());
 
     /* Normal creation of an erasure coding zone */
-    fs.getClient().createErasureCodingZone(testDir.toString());
+    fs.getClient().createErasureCodingZone(testDir.toString(), null);
 
     /* Verify files under the zone are striped */
     final Path ECFilePath = new Path(testDir, "foo");
@@ -77,7 +77,7 @@ public class TestErasureCodingZones {
     fs.mkdir(notEmpty, FsPermission.getDirDefault());
     fs.create(new Path(notEmpty, "foo"));
     try {
-      fs.getClient().createErasureCodingZone(notEmpty.toString());
+      fs.getClient().createErasureCodingZone(notEmpty.toString(), null);
       fail("Erasure coding zone on non-empty dir");
     } catch (IOException e) {
       assertExceptionContains("erasure coding zone for a non-empty directory", e);
@@ -87,10 +87,10 @@ public class TestErasureCodingZones {
     final Path zone1 = new Path("/zone1");
     final Path zone2 = new Path(zone1, "zone2");
     fs.mkdir(zone1, FsPermission.getDirDefault());
-    fs.getClient().createErasureCodingZone(zone1.toString());
+    fs.getClient().createErasureCodingZone(zone1.toString(), null);
     fs.mkdir(zone2, FsPermission.getDirDefault());
     try {
-      fs.getClient().createErasureCodingZone(zone2.toString());
+      fs.getClient().createErasureCodingZone(zone2.toString(), null);
       fail("Nested erasure coding zones");
     } catch (IOException e) {
       assertExceptionContains("already in an erasure coding zone", e);
@@ -100,7 +100,7 @@ public class TestErasureCodingZones {
     final Path fPath = new Path("/file");
     fs.create(fPath);
     try {
-      fs.getClient().createErasureCodingZone(fPath.toString());
+      fs.getClient().createErasureCodingZone(fPath.toString(), null);
       fail("Erasure coding zone on file");
     } catch (IOException e) {
       assertExceptionContains("erasure coding zone for a file", e);
@@ -113,8 +113,8 @@ public class TestErasureCodingZones {
     final Path dstECDir = new Path("/dstEC");
     fs.mkdir(srcECDir, FsPermission.getDirDefault());
     fs.mkdir(dstECDir, FsPermission.getDirDefault());
-    fs.getClient().createErasureCodingZone(srcECDir.toString());
+    fs.getClient().createErasureCodingZone(srcECDir.toString(), null);
-    fs.getClient().createErasureCodingZone(dstECDir.toString());
+    fs.getClient().createErasureCodingZone(dstECDir.toString(), null);
     final Path srcFile = new Path(srcECDir, "foo");
     fs.create(srcFile);
 
@@ -158,7 +158,7 @@ public class TestErasureCodingZones {
     // dir ECInfo before creating ec zone
     assertNull(fs.getClient().getErasureCodingInfo(src));
     // dir ECInfo after creating ec zone
-    fs.getClient().createErasureCodingZone(src);
+    fs.getClient().createErasureCodingZone(src, null);
     verifyErasureCodingInfo(src);
     fs.create(new Path(ecDir, "/child1")).close();
     // verify for the files in ec zone
@@ -182,4 +182,4 @@ public class TestErasureCodingZones {
     assertEquals("Default chunkSize should be used",
         ECSchema.DEFAULT_CHUNK_SIZE, schema.getChunkSize());
   }
-}
+}

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestAddStripedBlocks.java

@@ -68,7 +68,7 @@ public class TestAddStripedBlocks {
         .numDataNodes(GROUP_SIZE).build();
     cluster.waitActive();
     dfs = cluster.getFileSystem();
-    dfs.getClient().createErasureCodingZone("/");
+    dfs.getClient().createErasureCodingZone("/", null);
   }
 
   @After

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSEditLogLoader.java

@@ -445,7 +445,7 @@ public class TestFSEditLogLoader {
 
       //set the storage policy of the directory
       fs.mkdir(new Path(testDir), new FsPermission("755"));
-      fs.getClient().getNamenode().createErasureCodingZone(testDir);
+      fs.getClient().getNamenode().createErasureCodingZone(testDir, null);
 
       // Create a file with striped block
       Path p = new Path(testFilePath);
@@ -517,7 +517,7 @@ public class TestFSEditLogLoader {
 
       //set the storage policy of the directory
       fs.mkdir(new Path(testDir), new FsPermission("755"));
-      fs.getClient().getNamenode().createErasureCodingZone(testDir);
+      fs.getClient().getNamenode().createErasureCodingZone(testDir, null);
 
       //create a file with striped blocks
       Path p = new Path(testFilePath);

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/TestFSImage.java

@@ -135,7 +135,7 @@ public class TestFSImage {
   private void testSaveAndLoadStripedINodeFile(FSNamesystem fsn, Configuration conf,
                                                boolean isUC) throws IOException{
     // contruct a INode with StripedBlock for saving and loading
-    fsn.createErasureCodingZone("/", false);
+    fsn.createErasureCodingZone("/", null, false);
     long id = 123456789;
     byte[] name = "testSaveAndLoadInodeFile_testfile".getBytes();
     PermissionStatus permissionStatus = new PermissionStatus("testuser_a",
@@ -397,7 +397,7 @@ public class TestFSImage {
           .build();
       cluster.waitActive();
       DistributedFileSystem fs = cluster.getFileSystem();
-      fs.getClient().getNamenode().createErasureCodingZone("/");
+      fs.getClient().getNamenode().createErasureCodingZone("/", null);
       Path file = new Path("/striped");
       FSDataOutputStream out = fs.create(file);
       byte[] bytes = DFSTestUtil.generateSequentialBytes(0, BLOCK_SIZE);