http://git-wip-us.apache.org/repos/asf/hadoop/blob/6b6a63bb/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientProtocol.java ---------------------------------------------------------------------- diff --cc hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientProtocol.java index 0000000,8528999..7756bb9 mode 000000,100644..100644 --- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientProtocol.java +++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ClientProtocol.java @@@ -1,0 -1,1486 +1,1511 @@@ + /** + * 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.hdfs.protocol; + + import java.io.IOException; + import java.util.EnumSet; + import java.util.List; + + import org.apache.hadoop.classification.InterfaceAudience; + import org.apache.hadoop.classification.InterfaceStability; + import org.apache.hadoop.crypto.CryptoProtocolVersion; + import org.apache.hadoop.fs.BatchedRemoteIterator.BatchedEntries; + import org.apache.hadoop.fs.CacheFlag; + import org.apache.hadoop.fs.ContentSummary; + import org.apache.hadoop.fs.CreateFlag; + import org.apache.hadoop.fs.FsServerDefaults; + import org.apache.hadoop.fs.Options; + import org.apache.hadoop.fs.StorageType; + import org.apache.hadoop.fs.XAttr; + import org.apache.hadoop.fs.XAttrSetFlag; + import org.apache.hadoop.fs.permission.AclEntry; + import org.apache.hadoop.fs.permission.AclStatus; + import org.apache.hadoop.fs.permission.FsAction; + import org.apache.hadoop.fs.permission.FsPermission; + import org.apache.hadoop.hdfs.inotify.EventBatchList; + import org.apache.hadoop.hdfs.protocol.HdfsConstants.RollingUpgradeAction; + import org.apache.hadoop.hdfs.security.token.block.DataEncryptionKey; + import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier; + import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenSelector; + import org.apache.hadoop.hdfs.server.protocol.DatanodeStorageReport; + import org.apache.hadoop.io.EnumSetWritable; + import org.apache.hadoop.io.Text; + import org.apache.hadoop.io.retry.AtMostOnce; + import org.apache.hadoop.io.retry.Idempotent; + import org.apache.hadoop.security.KerberosInfo; + import org.apache.hadoop.security.token.Token; + import org.apache.hadoop.security.token.TokenInfo; + + import static org.apache.hadoop.hdfs.client.HdfsClientConfigKeys.DFS_NAMENODE_KERBEROS_PRINCIPAL_KEY; + + /********************************************************************** + * ClientProtocol is used by user code via the DistributedFileSystem class to + * communicate with the NameNode. User code can manipulate the directory + * namespace, as well as open/close file streams, etc. + * + **********************************************************************/ + @InterfaceAudience.Private + @InterfaceStability.Evolving + @KerberosInfo( + serverPrincipal = DFS_NAMENODE_KERBEROS_PRINCIPAL_KEY) + @TokenInfo(DelegationTokenSelector.class) + public interface ClientProtocol { + + /** + * Until version 69, this class ClientProtocol served as both + * the client interface to the NN AND the RPC protocol used to + * communicate with the NN. + * + * This class is used by both the DFSClient and the + * NN server side to insulate from the protocol serialization. + * + * If you are adding/changing this interface then you need to + * change both this class and ALSO related protocol buffer + * wire protocol definition in ClientNamenodeProtocol.proto. + * + * For more details on protocol buffer wire protocol, please see + * .../org/apache/hadoop/hdfs/protocolPB/overview.html + * + * The log of historical changes can be retrieved from the svn). + * 69: Eliminate overloaded method names. + * + * 69L is the last version id when this class was used for protocols + * serialization. DO not update this version any further. + */ + long versionID = 69L; + + /////////////////////////////////////// + // File contents + /////////////////////////////////////// + /** + * Get locations of the blocks of the specified file + * within the specified range. + * DataNode locations for each block are sorted by + * the proximity to the client. + * <p> + * Return {@link LocatedBlocks} which contains + * file length, blocks and their locations. + * DataNode locations for each block are sorted by + * the distance to the client's address. + * <p> + * The client will then have to contact + * one of the indicated DataNodes to obtain the actual data. + * + * @param src file name + * @param offset range start offset + * @param length range length + * + * @return file length and array of blocks with their locations + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> does not + * exist + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + LocatedBlocks getBlockLocations(String src, long offset, long length) + throws IOException; + + /** + * Get server default values for a number of configuration params. + * @return a set of server default configuration values + * @throws IOException + */ + @Idempotent + FsServerDefaults getServerDefaults() throws IOException; + + /** + * Create a new file entry in the namespace. + * <p> + * This will create an empty file specified by the source path. + * The path should reflect a full path originated at the root. + * The name-node does not have a notion of "current" directory for a client. + * <p> + * Once created, the file is visible and available for read to other clients. + * Although, other clients cannot {@link #delete(String, boolean)}, re-create + * or {@link #rename(String, String)} it until the file is completed + * or explicitly as a result of lease expiration. + * <p> + * Blocks have a maximum size. Clients that intend to create + * multi-block files must also use + * {@link #addBlock} + * + * @param src path of the file being created. + * @param masked masked permission. + * @param clientName name of the current client. + * @param flag indicates whether the file should be + * overwritten if it already exists or create if it does not exist or append. + * @param createParent create missing parent directory if true + * @param replication block replication factor. + * @param blockSize maximum block size. + * @param supportedVersions CryptoProtocolVersions supported by the client + * + * @return the status of the created file, it could be null if the server + * doesn't support returning the file status + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws AlreadyBeingCreatedException if the path does not exist. + * @throws DSQuotaExceededException If file creation violates disk space + * quota restriction + * @throws org.apache.hadoop.fs.FileAlreadyExistsException If file + * <code>src</code> already exists + * @throws java.io.FileNotFoundException If parent of <code>src</code> does + * not exist and <code>createParent</code> is false + * @throws org.apache.hadoop.fs.ParentNotDirectoryException If parent of + * <code>src</code> is not a directory. + * @throws NSQuotaExceededException If file creation violates name space + * quota restriction + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException create not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + * + * RuntimeExceptions: + * @throws org.apache.hadoop.fs.InvalidPathException Path <code>src</code> is + * invalid + * <p> + * <em>Note that create with {@link CreateFlag#OVERWRITE} is idempotent.</em> + */ + @AtMostOnce + HdfsFileStatus create(String src, FsPermission masked, + String clientName, EnumSetWritable<CreateFlag> flag, + boolean createParent, short replication, long blockSize, + CryptoProtocolVersion[] supportedVersions) + throws IOException; + + /** + * Append to the end of the file. + * @param src path of the file being created. + * @param clientName name of the current client. + * @param flag indicates whether the data is appended to a new block. + * @return wrapper with information about the last partial block and file + * status if any + * @throws org.apache.hadoop.security.AccessControlException if permission to + * append file is denied by the system. As usually on the client side the + * exception will be wrapped into + * {@link org.apache.hadoop.ipc.RemoteException}. + * Allows appending to an existing file if the server is + * configured with the parameter dfs.support.append set to true, otherwise + * throws an IOException. + * + * @throws org.apache.hadoop.security.AccessControlException If permission to + * append to file is denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws DSQuotaExceededException If append violates disk space quota + * restriction + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException append not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred. + * + * RuntimeExceptions: + * @throws UnsupportedOperationException if append is not supported + */ + @AtMostOnce + LastBlockWithStatus append(String src, String clientName, + EnumSetWritable<CreateFlag> flag) throws IOException; + + /** + * Set replication for an existing file. + * <p> + * The NameNode sets replication to the new value and returns. + * The actual block replication is not expected to be performed during + * this method call. The blocks will be populated or removed in the + * background as the result of the routine block maintenance procedures. + * + * @param src file name + * @param replication new replication + * + * @return true if successful; + * false if file does not exist or is a directory + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws DSQuotaExceededException If replication violates disk space + * quota restriction + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @Idempotent + boolean setReplication(String src, short replication) + throws IOException; + + /** + * Get all the available block storage policies. + * @return All the in-use block storage policies currently. + */ + @Idempotent + BlockStoragePolicy[] getStoragePolicies() throws IOException; + + /** + * Set the storage policy for a file/directory. + * @param src Path of an existing file/directory. + * @param policyName The name of the storage policy + * @throws SnapshotAccessControlException If access is denied + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>src</code> + * contains a symlink + * @throws java.io.FileNotFoundException If file/dir <code>src</code> is not + * found + * @throws QuotaExceededException If changes violate the quota restriction + */ + @Idempotent + void setStoragePolicy(String src, String policyName) + throws IOException; + + /** + * Get the storage policy for a file/directory. + * @param path + * Path of an existing file/directory. + * @throws AccessControlException + * If access is denied + * @throws org.apache.hadoop.fs.UnresolvedLinkException + * if <code>src</code> contains a symlink + * @throws java.io.FileNotFoundException + * If file/dir <code>src</code> is not found + */ + @Idempotent + BlockStoragePolicy getStoragePolicy(String path) throws IOException; + + /** + * Set permissions for an existing file/directory. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @Idempotent + void setPermission(String src, FsPermission permission) + throws IOException; + + /** + * Set Owner of a path (i.e. a file or a directory). + * The parameters username and groupname cannot both be null. + * @param src file path + * @param username If it is null, the original username remains unchanged. + * @param groupname If it is null, the original groupname remains unchanged. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @Idempotent + void setOwner(String src, String username, String groupname) + throws IOException; + + /** + * The client can give up on a block by calling abandonBlock(). + * The client can then either obtain a new block, or complete or abandon the + * file. + * Any partial writes to the block will be discarded. + * + * @param b Block to abandon + * @param fileId The id of the file where the block resides. Older clients + * will pass GRANDFATHER_INODE_ID here. + * @param src The path of the file where the block resides. + * @param holder Lease holder. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException file <code>src</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + void abandonBlock(ExtendedBlock b, long fileId, + String src, String holder) + throws IOException; + + /** + * A client that wants to write an additional block to the + * indicated filename (which must currently be open for writing) + * should call addBlock(). + * + * addBlock() allocates a new block and datanodes the block data + * should be replicated to. + * + * addBlock() also commits the previous block by reporting + * to the name-node the actual generation stamp and the length + * of the block that the client has transmitted to data-nodes. + * + * @param src the file being created + * @param clientName the name of the client that adds the block + * @param previous previous block + * @param excludeNodes a list of nodes that should not be + * allocated for the current block + * @param fileId the id uniquely identifying a file + * @param favoredNodes the list of nodes where the client wants the blocks. + * Nodes are identified by either host name or address. + * + * @return LocatedBlock allocated block information. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.NotReplicatedYetException + * previous blocks of the file are not replicated yet. + * Blocks cannot be added until replication completes. + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException create not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + LocatedBlock addBlock(String src, String clientName, + ExtendedBlock previous, DatanodeInfo[] excludeNodes, long fileId, + String[] favoredNodes) + throws IOException; + + /** + * Get a datanode for an existing pipeline. + * + * @param src the file being written + * @param fileId the ID of the file being written + * @param blk the block being written + * @param existings the existing nodes in the pipeline + * @param excludes the excluded nodes + * @param numAdditionalNodes number of additional datanodes + * @param clientName the name of the client + * + * @return the located block. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException create not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + LocatedBlock getAdditionalDatanode(final String src, + final long fileId, final ExtendedBlock blk, + final DatanodeInfo[] existings, + final String[] existingStorageIDs, + final DatanodeInfo[] excludes, + final int numAdditionalNodes, final String clientName + ) throws IOException; + + /** + * The client is done writing data to the given filename, and would + * like to complete it. + * + * The function returns whether the file has been closed successfully. + * If the function returns false, the caller should try again. + * + * close() also commits the last block of file by reporting + * to the name-node the actual generation stamp and the length + * of the block that the client has transmitted to data-nodes. + * + * A call to complete() will not return true until all the file's + * blocks have been replicated the minimum number of times. Thus, + * DataNode failures may cause a client to call complete() several + * times before succeeding. + * + * @param src the file being created + * @param clientName the name of the client that adds the block + * @param last the last block info + * @param fileId the id uniquely identifying a file + * + * @return true if all file blocks are minimally replicated or false otherwise + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException create not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + boolean complete(String src, String clientName, + ExtendedBlock last, long fileId) + throws IOException; + + /** + * The client wants to report corrupted blocks (blocks with specified + * locations on datanodes). + * @param blocks Array of located blocks to report + */ + @Idempotent + void reportBadBlocks(LocatedBlock[] blocks) throws IOException; + + /////////////////////////////////////// + // Namespace management + /////////////////////////////////////// + /** + * Rename an item in the file system namespace. + * @param src existing file or directory name. + * @param dst new name. + * @return true if successful, or false if the old name does not exist + * or if the new name already belongs to the namespace. + * + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException an I/O error occurred + */ + @AtMostOnce + boolean rename(String src, String dst) + throws IOException; + + /** + * Moves blocks from srcs to trg and delete srcs. + * + * @param trg existing file + * @param srcs - list of existing files (same block size, same replication) + * @throws IOException if some arguments are invalid + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>trg</code> or + * <code>srcs</code> contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + */ + @AtMostOnce + void concat(String trg, String[] srcs) + throws IOException; + + /** + * Rename src to dst. + * <ul> + * <li>Fails if src is a file and dst is a directory. + * <li>Fails if src is a directory and dst is a file. + * <li>Fails if the parent of dst does not exist or is a file. + * </ul> + * <p> + * Without OVERWRITE option, rename fails if the dst already exists. + * With OVERWRITE option, rename overwrites the dst, if it is a file + * or an empty directory. Rename fails if dst is a non-empty directory. + * <p> + * This implementation of rename is atomic. + * <p> + * @param src existing file or directory name. + * @param dst new name. + * @param options Rename options + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws DSQuotaExceededException If rename violates disk space + * quota restriction + * @throws org.apache.hadoop.fs.FileAlreadyExistsException If <code>dst</code> + * already exists and <code>options</code> has + * {@link org.apache.hadoop.fs.Options.Rename#OVERWRITE} option + * false. + * @throws java.io.FileNotFoundException If <code>src</code> does not exist + * @throws NSQuotaExceededException If rename violates namespace + * quota restriction + * @throws org.apache.hadoop.fs.ParentNotDirectoryException If parent of + * <code>dst</code> is not a directory + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException rename not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> or + * <code>dst</code> contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @AtMostOnce + void rename2(String src, String dst, Options.Rename... options) + throws IOException; + + /** + * Truncate file src to new size. + * <ul> + * <li>Fails if src is a directory. + * <li>Fails if src does not exist. + * <li>Fails if src is not closed. + * <li>Fails if new size is greater than current size. + * </ul> + * <p> + * This implementation of truncate is purely a namespace operation if truncate + * occurs at a block boundary. Requires DataNode block recovery otherwise. + * <p> + * @param src existing file + * @param newLength the target size + * + * @return true if client does not need to wait for block recovery, + * false if client needs to wait for block recovery. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException truncate + * not allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @Idempotent + boolean truncate(String src, long newLength, String clientName) + throws IOException; + + /** + * Delete the given file or directory from the file system. + * <p> + * same as delete but provides a way to avoid accidentally + * deleting non empty directories programmatically. + * @param src existing name + * @param recursive if true deletes a non empty directory recursively, + * else throws an exception. + * @return true only if the existing file or directory was actually removed + * from the file system. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws java.io.FileNotFoundException If file <code>src</code> is not found + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException create not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @AtMostOnce + boolean delete(String src, boolean recursive) + throws IOException; + + /** + * Create a directory (or hierarchy of directories) with the given + * name and permission. + * + * @param src The path of the directory being created + * @param masked The masked permission of the directory being created + * @param createParent create missing parent directory if true + * + * @return True if the operation success. + * + * @throws org.apache.hadoop.security.AccessControlException If access is + * denied + * @throws org.apache.hadoop.fs.FileAlreadyExistsException If <code>src</code> + * already exists + * @throws java.io.FileNotFoundException If parent of <code>src</code> does + * not exist and <code>createParent</code> is false + * @throws NSQuotaExceededException If file creation violates quota + * restriction + * @throws org.apache.hadoop.fs.ParentNotDirectoryException If parent of + * <code>src</code> is not a directory + * @throws org.apache.hadoop.hdfs.server.namenode.SafeModeException create not + * allowed in safemode + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred. + * + * RunTimeExceptions: + * @throws org.apache.hadoop.fs.InvalidPathException If <code>src</code> is + * invalid + */ + @Idempotent + boolean mkdirs(String src, FsPermission masked, boolean createParent) + throws IOException; + + /** + * Get a partial listing of the indicated directory. + * + * @param src the directory name + * @param startAfter the name to start listing after encoded in java UTF8 + * @param needLocation if the FileStatus should contain block locations + * + * @return a partial listing starting after startAfter + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>src</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException If <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + DirectoryListing getListing(String src, byte[] startAfter, + boolean needLocation) throws IOException; + + /** + * Get listing of all the snapshottable directories. + * + * @return Information about all the current snapshottable directory + * @throws IOException If an I/O error occurred + */ + @Idempotent + SnapshottableDirectoryStatus[] getSnapshottableDirListing() + throws IOException; + + /////////////////////////////////////// + // System issues and management + /////////////////////////////////////// + + /** + * Client programs can cause stateful changes in the NameNode + * that affect other clients. A client may obtain a file and + * neither abandon nor complete it. A client might hold a series + * of locks that prevent other clients from proceeding. + * Clearly, it would be bad if a client held a bunch of locks + * that it never gave up. This can happen easily if the client + * dies unexpectedly. + * <p> + * So, the NameNode will revoke the locks and live file-creates + * for clients that it thinks have died. A client tells the + * NameNode that it is still alive by periodically calling + * renewLease(). If a certain amount of time passes since + * the last call to renewLease(), the NameNode assumes the + * client has died. + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws IOException If an I/O error occurred + */ + @Idempotent + void renewLease(String clientName) throws IOException; + + /** + * Start lease recovery. + * Lightweight NameNode operation to trigger lease recovery + * + * @param src path of the file to start lease recovery + * @param clientName name of the current client + * @return true if the file is already closed + * @throws IOException + */ + @Idempotent + boolean recoverLease(String src, String clientName) throws IOException; + + int GET_STATS_CAPACITY_IDX = 0; + int GET_STATS_USED_IDX = 1; + int GET_STATS_REMAINING_IDX = 2; + int GET_STATS_UNDER_REPLICATED_IDX = 3; + int GET_STATS_CORRUPT_BLOCKS_IDX = 4; + int GET_STATS_MISSING_BLOCKS_IDX = 5; + int GET_STATS_MISSING_REPL_ONE_BLOCKS_IDX = 6; + + /** + * Get a set of statistics about the filesystem. + * Right now, only seven values are returned. + * <ul> + * <li> [0] contains the total storage capacity of the system, in bytes.</li> + * <li> [1] contains the total used space of the system, in bytes.</li> + * <li> [2] contains the available storage of the system, in bytes.</li> + * <li> [3] contains number of under replicated blocks in the system.</li> + * <li> [4] contains number of blocks with a corrupt replica. </li> + * <li> [5] contains number of blocks without any good replicas left. </li> + * <li> [6] contains number of blocks which have replication factor + * 1 and have lost the only replica. </li> + * </ul> + * Use public constants like {@link #GET_STATS_CAPACITY_IDX} in place of + * actual numbers to index into the array. + */ + @Idempotent + long[] getStats() throws IOException; + + /** + * Get a report on the system's current datanodes. + * One DatanodeInfo object is returned for each DataNode. + * Return live datanodes if type is LIVE; dead datanodes if type is DEAD; + * otherwise all datanodes if type is ALL. + */ + @Idempotent + DatanodeInfo[] getDatanodeReport(HdfsConstants.DatanodeReportType type) + throws IOException; + + /** + * Get a report on the current datanode storages. + */ + @Idempotent + DatanodeStorageReport[] getDatanodeStorageReport( + HdfsConstants.DatanodeReportType type) throws IOException; + + /** + * Get the block size for the given file. + * @param filename The name of the file + * @return The number of bytes in each block + * @throws IOException + * @throws org.apache.hadoop.fs.UnresolvedLinkException if the path contains + * a symlink. + */ + @Idempotent + long getPreferredBlockSize(String filename) + throws IOException; + + /** + * Enter, leave or get safe mode. + * <p> + * Safe mode is a name node state when it + * <ol><li>does not accept changes to name space (read-only), and</li> + * <li>does not replicate or delete blocks.</li></ol> + * + * <p> + * Safe mode is entered automatically at name node startup. + * Safe mode can also be entered manually using + * {@link #setSafeMode(HdfsConstants.SafeModeAction,boolean) + * setSafeMode(SafeModeAction.SAFEMODE_ENTER,false)}. + * <p> + * At startup the name node accepts data node reports collecting + * information about block locations. + * In order to leave safe mode it needs to collect a configurable + * percentage called threshold of blocks, which satisfy the minimal + * replication condition. + * The minimal replication condition is that each block must have at least + * <tt>dfs.namenode.replication.min</tt> replicas. + * When the threshold is reached the name node extends safe mode + * for a configurable amount of time + * to let the remaining data nodes to check in before it + * will start replicating missing blocks. + * Then the name node leaves safe mode. + * <p> + * If safe mode is turned on manually using + * {@link #setSafeMode(HdfsConstants.SafeModeAction,boolean) + * setSafeMode(SafeModeAction.SAFEMODE_ENTER,false)} + * then the name node stays in safe mode until it is manually turned off + * using {@link #setSafeMode(HdfsConstants.SafeModeAction,boolean) + * setSafeMode(SafeModeAction.SAFEMODE_LEAVE,false)}. + * Current state of the name node can be verified using + * {@link #setSafeMode(HdfsConstants.SafeModeAction,boolean) + * setSafeMode(SafeModeAction.SAFEMODE_GET,false)} + * <h4>Configuration parameters:</h4> + * <tt>dfs.safemode.threshold.pct</tt> is the threshold parameter.<br> + * <tt>dfs.safemode.extension</tt> is the safe mode extension parameter.<br> + * <tt>dfs.namenode.replication.min</tt> is the minimal replication parameter. + * + * <h4>Special cases:</h4> + * The name node does not enter safe mode at startup if the threshold is + * set to 0 or if the name space is empty.<br> + * If the threshold is set to 1 then all blocks need to have at least + * minimal replication.<br> + * If the threshold value is greater than 1 then the name node will not be + * able to turn off safe mode automatically.<br> + * Safe mode can always be turned off manually. + * + * @param action <ul> <li>0 leave safe mode;</li> + * <li>1 enter safe mode;</li> + * <li>2 get safe mode state.</li></ul> + * @param isChecked If true then action will be done only in ActiveNN. + * + * @return <ul><li>0 if the safe mode is OFF or</li> + * <li>1 if the safe mode is ON.</li></ul> + * + * @throws IOException + */ + @Idempotent + boolean setSafeMode(HdfsConstants.SafeModeAction action, boolean isChecked) + throws IOException; + + /** + * Save namespace image. + * <p> + * Saves current namespace into storage directories and reset edits log. + * Requires superuser privilege and safe mode. + * + * @param timeWindow NameNode does a checkpoint if the latest checkpoint was + * done beyond the given time period (in seconds). + * @param txGap NameNode does a checkpoint if the gap between the latest + * checkpoint and the latest transaction id is greater this gap. + * @return whether an extra checkpoint has been done + * + * @throws IOException if image creation failed. + */ + @AtMostOnce + boolean saveNamespace(long timeWindow, long txGap) throws IOException; + + /** + * Roll the edit log. + * Requires superuser privileges. + * + * @throws org.apache.hadoop.security.AccessControlException if the superuser + * privilege is violated + * @throws IOException if log roll fails + * @return the txid of the new segment + */ + @Idempotent + long rollEdits() throws IOException; + + /** + * Enable/Disable restore failed storage. + * <p> + * sets flag to enable restore of failed storage replicas + * + * @throws org.apache.hadoop.security.AccessControlException if the superuser + * privilege is violated. + */ + @Idempotent + boolean restoreFailedStorage(String arg) throws IOException; + + /** + * Tells the namenode to reread the hosts and exclude files. + * @throws IOException + */ + @Idempotent + void refreshNodes() throws IOException; + + /** + * Finalize previous upgrade. + * Remove file system state saved during the upgrade. + * The upgrade will become irreversible. + * + * @throws IOException + */ + @Idempotent + void finalizeUpgrade() throws IOException; + + /** + * Rolling upgrade operations. + * @param action either query, prepare or finalize. + * @return rolling upgrade information. On query, if no upgrade is in + * progress, returns null. + */ + @Idempotent + RollingUpgradeInfo rollingUpgrade(RollingUpgradeAction action) + throws IOException; + + /** + * @return CorruptFileBlocks, containing a list of corrupt files (with + * duplicates if there is more than one corrupt block in a file) + * and a cookie + * @throws IOException + * + * Each call returns a subset of the corrupt files in the system. To obtain + * all corrupt files, call this method repeatedly and each time pass in the + * cookie returned from the previous call. + */ + @Idempotent + CorruptFileBlocks listCorruptFileBlocks(String path, String cookie) + throws IOException; + + /** + * Dumps namenode data structures into specified file. If the file + * already exists, then append. + * + * @throws IOException + */ + @Idempotent + void metaSave(String filename) throws IOException; + + /** + * Tell all datanodes to use a new, non-persistent bandwidth value for + * dfs.balance.bandwidthPerSec. + * + * @param bandwidth Blanacer bandwidth in bytes per second for this datanode. + * @throws IOException + */ + @Idempotent + void setBalancerBandwidth(long bandwidth) throws IOException; + + /** + * Get the file info for a specific file or directory. + * @param src The string representation of the path to the file + * + * @return object containing information regarding the file + * or null if file not found + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>src</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException if the path contains + * a symlink. + * @throws IOException If an I/O error occurred + */ + @Idempotent + HdfsFileStatus getFileInfo(String src) throws IOException; + + /** + * Get the close status of a file. + * @param src The string representation of the path to the file + * + * @return return true if file is closed + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>src</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException if the path contains + * a symlink. + * @throws IOException If an I/O error occurred + */ + @Idempotent + boolean isFileClosed(String src) throws IOException; + + /** + * Get the file info for a specific file or directory. If the path + * refers to a symlink then the FileStatus of the symlink is returned. + * @param src The string representation of the path to the file + * + * @return object containing information regarding the file + * or null if file not found + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>src</code> + * contains a symlink + * @throws IOException If an I/O error occurred + */ + @Idempotent + HdfsFileStatus getFileLinkInfo(String src) throws IOException; + + /** + * Get {@link ContentSummary} rooted at the specified directory. + * @param path The string representation of the path + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>path</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>path</code> + * contains a symlink. + * @throws IOException If an I/O error occurred + */ + @Idempotent + ContentSummary getContentSummary(String path) throws IOException; + + /** + * Set the quota for a directory. + * @param path The string representation of the path to the directory + * @param namespaceQuota Limit on the number of names in the tree rooted + * at the directory + * @param storagespaceQuota Limit on storage space occupied all the files + * under this directory. + * @param type StorageType that the space quota is intended to be set on. + * It may be null when called by traditional space/namespace + * quota. When type is is not null, the storagespaceQuota + * parameter is for type specified and namespaceQuota must be + * {@link HdfsConstants#QUOTA_DONT_SET}. + * + * <br><br> + * + * The quota can have three types of values : (1) 0 or more will set + * the quota to that value, (2) {@link HdfsConstants#QUOTA_DONT_SET} implies + * the quota will not be changed, and (3) {@link HdfsConstants#QUOTA_RESET} + * implies the quota will be reset. Any other value is a runtime error. + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>path</code> is not found + * @throws QuotaExceededException if the directory size + * is greater than the given quota + * @throws org.apache.hadoop.fs.UnresolvedLinkException if the + * <code>path</code> contains a symlink. + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @Idempotent + void setQuota(String path, long namespaceQuota, long storagespaceQuota, + StorageType type) throws IOException; + + /** + * Write all metadata for this file into persistent storage. + * The file must be currently open for writing. + * @param src The string representation of the path + * @param inodeId The inode ID, or GRANDFATHER_INODE_ID if the client is + * too old to support fsync with inode IDs. + * @param client The string representation of the client + * @param lastBlockLength The length of the last block (under construction) + * to be reported to NameNode + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>src</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>src</code> + * contains a symlink. + * @throws IOException If an I/O error occurred + */ + @Idempotent + void fsync(String src, long inodeId, String client, long lastBlockLength) + throws IOException; + + /** + * Sets the modification and access time of the file to the specified time. + * @param src The string representation of the path + * @param mtime The number of milliseconds since Jan 1, 1970. + * Setting mtime to -1 means that modification time should not + * be set by this call. + * @param atime The number of milliseconds since Jan 1, 1970. + * Setting atime to -1 means that access time should not be set + * by this call. + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException file <code>src</code> is not found + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>src</code> + * contains a symlink. + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @Idempotent + void setTimes(String src, long mtime, long atime) throws IOException; + + /** + * Create symlink to a file or directory. + * @param target The path of the destination that the + * link points to. + * @param link The path of the link being created. + * @param dirPerm permissions to use when creating parent directories + * @param createParent - if true then missing parent dirs are created + * if false then parent must exist + * + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws org.apache.hadoop.fs.FileAlreadyExistsException If file + * <code>link</code> already exists + * @throws java.io.FileNotFoundException If parent of <code>link</code> does + * not exist and <code>createParent</code> is false + * @throws org.apache.hadoop.fs.ParentNotDirectoryException If parent of + * <code>link</code> is not a directory. + * @throws org.apache.hadoop.fs.UnresolvedLinkException if <code>link</code> + * contains a symlink. + * @throws SnapshotAccessControlException if path is in RO snapshot + * @throws IOException If an I/O error occurred + */ + @AtMostOnce + void createSymlink(String target, String link, FsPermission dirPerm, + boolean createParent) throws IOException; + + /** + * Return the target of the given symlink. If there is an intermediate + * symlink in the path (ie a symlink leading up to the final path component) + * then the given path is returned with this symlink resolved. + * + * @param path The path with a link that needs resolution. + * @return The path after resolving the first symbolic link in the path. + * @throws org.apache.hadoop.security.AccessControlException permission denied + * @throws java.io.FileNotFoundException If <code>path</code> does not exist + * @throws IOException If the given path does not refer to a symlink + * or an I/O error occurred + */ + @Idempotent + String getLinkTarget(String path) throws IOException; + + /** + * Get a new generation stamp together with an access token for + * a block under construction + * + * This method is called only when a client needs to recover a failed + * pipeline or set up a pipeline for appending to a block. + * + * @param block a block + * @param clientName the name of the client + * @return a located block with a new generation stamp and an access token + * @throws IOException if any error occurs + */ + @Idempotent + LocatedBlock updateBlockForPipeline(ExtendedBlock block, + String clientName) throws IOException; + + /** + * Update a pipeline for a block under construction. + * + * @param clientName the name of the client + * @param oldBlock the old block + * @param newBlock the new block containing new generation stamp and length + * @param newNodes datanodes in the pipeline + * @throws IOException if any error occurs + */ + @AtMostOnce + void updatePipeline(String clientName, ExtendedBlock oldBlock, + ExtendedBlock newBlock, DatanodeID[] newNodes, String[] newStorageIDs) + throws IOException; + + /** + * Get a valid Delegation Token. + * + * @param renewer the designated renewer for the token + * @return Token<DelegationTokenIdentifier> + * @throws IOException + */ + @Idempotent + Token<DelegationTokenIdentifier> getDelegationToken(Text renewer) + throws IOException; + + /** + * Renew an existing delegation token. + * + * @param token delegation token obtained earlier + * @return the new expiration time + * @throws IOException + */ + @Idempotent + long renewDelegationToken(Token<DelegationTokenIdentifier> token) + throws IOException; + + /** + * Cancel an existing delegation token. + * + * @param token delegation token + * @throws IOException + */ + @Idempotent + void cancelDelegationToken(Token<DelegationTokenIdentifier> token) + throws IOException; + + /** + * @return encryption key so a client can encrypt data sent via the + * DataTransferProtocol to/from DataNodes. + * @throws IOException + */ + @Idempotent + DataEncryptionKey getDataEncryptionKey() throws IOException; + + /** + * Create a snapshot. + * @param snapshotRoot the path that is being snapshotted + * @param snapshotName name of the snapshot created + * @return the snapshot path. + * @throws IOException + */ + @AtMostOnce + String createSnapshot(String snapshotRoot, String snapshotName) + throws IOException; + + /** + * Delete a specific snapshot of a snapshottable directory. + * @param snapshotRoot The snapshottable directory + * @param snapshotName Name of the snapshot for the snapshottable directory + * @throws IOException + */ + @AtMostOnce + void deleteSnapshot(String snapshotRoot, String snapshotName) + throws IOException; + + /** + * Rename a snapshot. + * @param snapshotRoot the directory path where the snapshot was taken + * @param snapshotOldName old name of the snapshot + * @param snapshotNewName new name of the snapshot + * @throws IOException + */ + @AtMostOnce + void renameSnapshot(String snapshotRoot, String snapshotOldName, + String snapshotNewName) throws IOException; + + /** + * Allow snapshot on a directory. + * @param snapshotRoot the directory to be snapped + * @throws IOException on error + */ + @Idempotent + void allowSnapshot(String snapshotRoot) + throws IOException; + + /** + * Disallow snapshot on a directory. + * @param snapshotRoot the directory to disallow snapshot + * @throws IOException on error + */ + @Idempotent + void disallowSnapshot(String snapshotRoot) + throws IOException; + + /** + * Get the difference between two snapshots, or between a snapshot and the + * current tree of a directory. + * + * @param snapshotRoot + * full path of the directory where snapshots are taken + * @param fromSnapshot + * snapshot name of the from point. Null indicates the current + * tree + * @param toSnapshot + * snapshot name of the to point. Null indicates the current + * tree. + * @return The difference report represented as a {@link SnapshotDiffReport}. + * @throws IOException on error + */ + @Idempotent + SnapshotDiffReport getSnapshotDiffReport(String snapshotRoot, + String fromSnapshot, String toSnapshot) throws IOException; + + /** + * Add a CacheDirective to the CacheManager. + * + * @param directive A CacheDirectiveInfo to be added + * @param flags {@link CacheFlag}s to use for this operation. + * @return A CacheDirectiveInfo associated with the added directive + * @throws IOException if the directive could not be added + */ + @AtMostOnce + long addCacheDirective(CacheDirectiveInfo directive, + EnumSet<CacheFlag> flags) throws IOException; + + /** + * Modify a CacheDirective in the CacheManager. + * + * @param flags {@link CacheFlag}s to use for this operation. + * @throws IOException if the directive could not be modified + */ + @AtMostOnce + void modifyCacheDirective(CacheDirectiveInfo directive, + EnumSet<CacheFlag> flags) throws IOException; + + /** + * Remove a CacheDirectiveInfo from the CacheManager. + * + * @param id of a CacheDirectiveInfo + * @throws IOException if the cache directive could not be removed + */ + @AtMostOnce + void removeCacheDirective(long id) throws IOException; + + /** + * List the set of cached paths of a cache pool. Incrementally fetches results + * from the server. + * + * @param prevId The last listed entry ID, or -1 if this is the first call to + * listCacheDirectives. + * @param filter Parameters to use to filter the list results, + * or null to display all directives visible to us. + * @return A batch of CacheDirectiveEntry objects. + */ + @Idempotent + BatchedEntries<CacheDirectiveEntry> listCacheDirectives( + long prevId, CacheDirectiveInfo filter) throws IOException; + + /** + * Add a new cache pool. + * + * @param info Description of the new cache pool + * @throws IOException If the request could not be completed. + */ + @AtMostOnce + void addCachePool(CachePoolInfo info) throws IOException; + + /** + * Modify an existing cache pool. + * + * @param req + * The request to modify a cache pool. + * @throws IOException + * If the request could not be completed. + */ + @AtMostOnce + void modifyCachePool(CachePoolInfo req) throws IOException; + + /** + * Remove a cache pool. + * + * @param pool name of the cache pool to remove. + * @throws IOException if the cache pool did not exist, or could not be + * removed. + */ + @AtMostOnce + void removeCachePool(String pool) throws IOException; + + /** + * List the set of cache pools. Incrementally fetches results from the server. + * + * @param prevPool name of the last pool listed, or the empty string if this + * is the first invocation of listCachePools + * @return A batch of CachePoolEntry objects. + */ + @Idempotent + BatchedEntries<CachePoolEntry> listCachePools(String prevPool) + throws IOException; + + /** + * Modifies ACL entries of files and directories. This method can add new ACL + * entries or modify the permissions on existing ACL entries. All existing + * ACL entries that are not specified in this call are retained without + * changes. (Modifications are merged into the current ACL.) + */ + @Idempotent + void modifyAclEntries(String src, List<AclEntry> aclSpec) + throws IOException; + + /** + * Removes ACL entries from files and directories. Other ACL entries are + * retained. + */ + @Idempotent + void removeAclEntries(String src, List<AclEntry> aclSpec) + throws IOException; + + /** + * Removes all default ACL entries from files and directories. + */ + @Idempotent + void removeDefaultAcl(String src) throws IOException; + + /** + * Removes all but the base ACL entries of files and directories. The entries + * for user, group, and others are retained for compatibility with permission + * bits. + */ + @Idempotent + void removeAcl(String src) throws IOException; + + /** + * Fully replaces ACL of files and directories, discarding all existing + * entries. + */ + @Idempotent + void setAcl(String src, List<AclEntry> aclSpec) throws IOException; + + /** + * Gets the ACLs of files and directories. + */ + @Idempotent + AclStatus getAclStatus(String src) throws IOException; + + /** + * Create an encryption zone. + */ + @AtMostOnce + void createEncryptionZone(String src, String keyName) + throws IOException; + + /** + * Get the encryption zone for a path. + */ + @Idempotent + EncryptionZone getEZForPath(String src) + throws IOException; + + /** + * Used to implement cursor-based batched listing of {@EncryptionZone}s. + * + * @param prevId ID of the last item in the previous batch. If there is no + * previous batch, a negative value can be used. + * @return Batch of encryption zones. + */ + @Idempotent + BatchedEntries<EncryptionZone> listEncryptionZones( + long prevId) throws IOException; + + /** + * Set xattr of a file or directory. + * The name must be prefixed with the namespace followed by ".". For example, + * "user.attr". + * <p/> + * Refer to the HDFS extended attributes user documentation for details. + * + * @param src file or directory + * @param xAttr <code>XAttr</code> to set + * @param flag set flag + * @throws IOException + */ + @AtMostOnce + void setXAttr(String src, XAttr xAttr, EnumSet<XAttrSetFlag> flag) + throws IOException; + + /** + * Get xattrs of a file or directory. Values in xAttrs parameter are ignored. + * If xAttrs is null or empty, this is the same as getting all xattrs of the + * file or directory. Only those xattrs for which the logged-in user has + * permissions to view are returned. + * <p/> + * Refer to the HDFS extended attributes user documentation for details. + * + * @param src file or directory + * @param xAttrs xAttrs to get + * @return List<XAttr> <code>XAttr</code> list + * @throws IOException + */ + @Idempotent + List<XAttr> getXAttrs(String src, List<XAttr> xAttrs) + throws IOException; + + /** + * List the xattrs names for a file or directory. + * Only the xattr names for which the logged in user has the permissions to + * access will be returned. + * <p/> + * Refer to the HDFS extended attributes user documentation for details. + * + * @param src file or directory + * @return List<XAttr> <code>XAttr</code> list + * @throws IOException + */ + @Idempotent + List<XAttr> listXAttrs(String src) + throws IOException; + + /** + * Remove xattr of a file or directory.Value in xAttr parameter is ignored. + * The name must be prefixed with the namespace followed by ".". For example, + * "user.attr". + * <p/> + * Refer to the HDFS extended attributes user documentation for details. + * + * @param src file or directory + * @param xAttr <code>XAttr</code> to remove + * @throws IOException + */ + @AtMostOnce + void removeXAttr(String src, XAttr xAttr) throws IOException; + + /** + * Checks if the user can access a path. The mode specifies which access + * checks to perform. If the requested permissions are granted, then the + * method returns normally. If access is denied, then the method throws an + * {@link org.apache.hadoop.security.AccessControlException}. + * In general, applications should avoid using this method, due to the risk of + * time-of-check/time-of-use race conditions. The permissions on a file may + * change immediately after the access call returns. + * + * @param path Path to check + * @param mode type of access to check + * @throws org.apache.hadoop.security.AccessControlException if access is + * denied + * @throws java.io.FileNotFoundException if the path does not exist + * @throws IOException see specific implementation + */ + @Idempotent + void checkAccess(String path, FsAction mode) throws IOException; + + /** + * Get the highest txid the NameNode knows has been written to the edit + * log, or -1 if the NameNode's edit log is not yet open for write. Used as + * the starting point for the inotify event stream. + */ + @Idempotent + long getCurrentEditLogTxid() throws IOException; + + /** + * Get an ordered list of batches of events corresponding to the edit log + * transactions for txids equal to or greater than txid. + */ + @Idempotent + EventBatchList getEditsFromTxid(long txid) throws IOException; ++ ++ /** ++ * Create an erasure coding zone with specified policy, if any, otherwise ++ * default ++ */ ++ @AtMostOnce ++ void createErasureCodingZone(String src, ErasureCodingPolicy ecPolicy) ++ throws IOException; ++ ++ /** ++ * Get the erasure coding policies loaded in Namenode ++ * ++ * @throws IOException ++ */ ++ @Idempotent ++ ErasureCodingPolicy[] getErasureCodingPolicies() throws IOException; ++ ++ /** ++ * Get the information about the EC zone for the path ++ * ++ * @param src path to get the info for ++ * @throws IOException ++ */ ++ @Idempotent ++ ErasureCodingZone getErasureCodingZone(String src) throws IOException; + }
http://git-wip-us.apache.org/repos/asf/hadoop/blob/6b6a63bb/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ErasureCodingZone.java ---------------------------------------------------------------------- diff --cc hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ErasureCodingZone.java index 0000000,0000000..533b630 new file mode 100644 --- /dev/null +++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/ErasureCodingZone.java @@@ -1,0 -1,0 +1,54 @@@ ++/** ++ * 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.hdfs.protocol; ++ ++/** ++ * Information about the EC Zone at the specified path. ++ */ ++public class ErasureCodingZone { ++ ++ private String dir; ++ private ErasureCodingPolicy ecPolicy; ++ ++ public ErasureCodingZone(String dir, ErasureCodingPolicy ecPolicy) { ++ this.dir = dir; ++ this.ecPolicy = ecPolicy; ++ } ++ ++ /** ++ * Get directory of the EC zone. ++ * ++ * @return ++ */ ++ public String getDir() { ++ return dir; ++ } ++ ++ /** ++ * Get the erasure coding policy for the EC Zone ++ * ++ * @return ++ */ ++ public ErasureCodingPolicy getErasureCodingPolicy() { ++ return ecPolicy; ++ } ++ ++ @Override ++ public String toString() { ++ return "Dir: " + getDir() + ", Policy: " + ecPolicy; ++ } ++} http://git-wip-us.apache.org/repos/asf/hadoop/blob/6b6a63bb/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/HdfsConstants.java ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/hadoop/blob/6b6a63bb/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/web/JsonUtilClient.java ----------------------------------------------------------------------
