All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.apache.hadoop.hbase.master.ClusterSchema Maven / Gradle / Ivy

There is a newer version: 3.0.0-beta-1
Show newest version
/**
 * 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.hbase.master;

import java.io.IOException;
import java.util.List;

import org.apache.hadoop.hbase.NamespaceDescriptor;
import org.apache.hadoop.hbase.ServiceNotRunningException;
import org.apache.hadoop.hbase.master.procedure.ProcedurePrepareLatch;
import org.apache.yetus.audience.InterfaceAudience;
import org.apache.hadoop.hbase.util.NonceKey;

/**
 * View and edit the current cluster schema. Use this API making any modification to
 * namespaces, tables, etc.
 *
 * 

Implementation Notes

* Nonces are for when operation is non-idempotent to ensure once-only semantic, even * across process failures. */ // ClusterSchema is introduced to encapsulate schema modification. Currently the different aspects // are spread about the code base. This effort is about cleanup, shutting down access, and // coalescing common code. In particular, we'd contain filesystem modification. Other // benefits are to make all schema modification work the same way (one way to do an operation only // rather than the current approach where how an operation is done varies with context) and to make // it so clusterschema modification can stand apart from Master to faciliate standalone // testing. It is part of the filesystem refactor project that undoes the dependency on a // layout in HDFS that mimics our model of tables have regions have column families have files. // With this Interface in place, with all modifications going via this route where no filesystem // particulars are exposed, redoing our internals will take less effort. // // Currently ClusterSchema Interface will include namespace and table manipulation. Ideally a // form of this Interface will go all the ways down to the file manipulation level but currently // TBD. // // ClusterSchema is private to the Master; only the Master knows current cluster state and has // means of editing/altering it. // // TODO: Remove Server argument when MasterServices are passed. // TODO: We return Future in the below from most methods. It may change to return // a ProcedureFuture subsequently. @InterfaceAudience.Private public interface ClusterSchema { /** * Timeout for cluster operations in milliseconds. */ public static final String HBASE_MASTER_CLUSTER_SCHEMA_OPERATION_TIMEOUT_KEY = "hbase.master.cluster.schema.operation.timeout"; /** * Default operation timeout in milliseconds. */ public static final int DEFAULT_HBASE_MASTER_CLUSTER_SCHEMA_OPERATION_TIMEOUT = 5 * 60 * 1000; /** * For internals use only. Do not use! Provisionally part of this Interface. * Prefer the high-level APIs available elsewhere in this API. * @return Instance of {@link TableNamespaceManager} */ // TODO: Remove from here. Keep internal. This Interface is too high-level to host this accessor. TableNamespaceManager getTableNamespaceManager(); /** * Create a new Namespace. * @param namespaceDescriptor descriptor for new Namespace * @param nonceKey A unique identifier for this operation from the client or process. * @param latch A latch to block on for precondition validation * @return procedure id * @throws IOException if service is not running see {@link ServiceNotRunningException} */ long createNamespace(NamespaceDescriptor namespaceDescriptor, NonceKey nonceKey, ProcedurePrepareLatch latch) throws IOException; /** * Modify an existing Namespace. * @param nonceKey A unique identifier for this operation from the client or process. * @param latch A latch to block on for precondition validation * @return procedure id * @throws IOException if service is not running see {@link ServiceNotRunningException} */ long modifyNamespace(NamespaceDescriptor descriptor, NonceKey nonceKey, ProcedurePrepareLatch latch) throws IOException; /** * Delete an existing Namespace. * Only empty Namespaces (no tables) can be removed. * @param nonceKey A unique identifier for this operation from the client or process. * @param latch A latch to block on for precondition validation * @return procedure id * @throws IOException if service is not running see {@link ServiceNotRunningException} */ long deleteNamespace(String name, NonceKey nonceKey, ProcedurePrepareLatch latch) throws IOException; /** * Get a Namespace * @param name Name of the Namespace * @return Namespace descriptor for name * @throws IOException if namespace does not exist */ // No Future here because presumption is that the request will go against cached metadata so // return immediately -- no need of running a Procedure. NamespaceDescriptor getNamespace(String name) throws IOException; /** * Get all Namespaces * @return All Namespace descriptors */ List getNamespaces() throws IOException; }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy