/*
*
* 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.replication;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.util.Pair;
/**
* This provides an interface for maintaining a set of peer clusters. These peers are remote slave
* clusters that data is replicated to. A peer cluster can be in three different states:
*
* 1. Not-Registered - There is no notion of the peer cluster.
* 2. Registered - The peer has an id and is being tracked but there is no connection.
* 3. Connected - There is an active connection to the remote peer.
*
* In the registered or connected state, a peer cluster can either be enabled or disabled.
*/
@InterfaceAudience.Private
public interface ReplicationPeers {
/**
* Initialize the ReplicationPeers interface.
*/
void init() throws ReplicationException;
/**
* Add a new remote slave cluster for replication.
* @param peerId a short that identifies the cluster
* @param peerConfig configuration for the replication slave cluster
*/
void registerPeer(String peerId, ReplicationPeerConfig peerConfig)
throws ReplicationException;
/**
* Removes a remote slave cluster and stops the replication to it.
* @param peerId a short that identifies the cluster
*/
void unregisterPeer(String peerId) throws ReplicationException;
/**
* Method called after a peer has been connected. It will create a ReplicationPeer to track the
* newly connected cluster.
* @param peerId a short that identifies the cluster
* @return whether a ReplicationPeer was successfully created
* @throws ReplicationException
*/
boolean peerConnected(String peerId) throws ReplicationException;
/**
* Method called after a peer has been disconnected. It will remove the ReplicationPeer that
* tracked the disconnected cluster.
* @param peerId a short that identifies the cluster
*/
void peerDisconnected(String peerId);
/**
* Restart the replication to the specified remote slave cluster.
* @param peerId a short that identifies the cluster
*/
void enablePeer(String peerId) throws ReplicationException;
/**
* Stop the replication to the specified remote slave cluster.
* @param peerId a short that identifies the cluster
*/
void disablePeer(String peerId) throws ReplicationException;
/**
* Get the table and column-family list string of the peer from the underlying storage.
* @param peerId a short that identifies the cluster
*/
public Map<TableName, List<String>> getPeerTableCFsConfig(String peerId)
throws ReplicationException;
/**
* Set the table and column-family list string of the peer to the underlying storage.
* @param peerId a short that identifies the cluster
* @param tableCFs the table and column-family list which will be replicated for this peer
*/
public void setPeerTableCFsConfig(String peerId,
Map<TableName, ? extends Collection<String>> tableCFs)
throws ReplicationException;
/**
* Returns the ReplicationPeer for the specified connected peer. This ReplicationPeer will
* continue to track changes to the Peer's state and config. This method returns null if no
* peer has been connected with the given peerId.
* @param peerId id for the peer
* @return ReplicationPeer object
*/
ReplicationPeer getConnectedPeer(String peerId);
/**
* Returns the set of peerIds of the clusters that have been connected and have an underlying
* ReplicationPeer.
* @return a Set of Strings for peerIds
*/
public Set<String> getConnectedPeerIds();
/**
* Get the replication status for the specified connected remote slave cluster.
* The value might be read from cache, so it is recommended to
* use {@link #getStatusOfPeerFromBackingStore(String)}
* if reading the state after enabling or disabling it.
* @param peerId a short that identifies the cluster
* @return true if replication is enabled, false otherwise.
*/
boolean getStatusOfPeer(String peerId);
/**
* Get the replication status for the specified remote slave cluster, which doesn't
* have to be connected. The state is read directly from the backing store.
* @param peerId a short that identifies the cluster
* @return true if replication is enabled, false otherwise.
* @throws ReplicationException thrown if there's an error contacting the store
*/
boolean getStatusOfPeerFromBackingStore(String peerId) throws ReplicationException;
/**
* List the cluster replication configs of all remote slave clusters (whether they are
* enabled/disabled or connected/disconnected).
* @return A map of peer ids to peer cluster keys
*/
Map<String, ReplicationPeerConfig> getAllPeerConfigs();
/**
* List the peer ids of all remote slave clusters (whether they are enabled/disabled or
* connected/disconnected).
* @return A list of peer ids
*/
List<String> getAllPeerIds();
/**
* Returns the configured ReplicationPeerConfig for this peerId
* @param peerId a short name that identifies the cluster
* @return ReplicationPeerConfig for the peer
*/
ReplicationPeerConfig getReplicationPeerConfig(String peerId) throws ReplicationException;
/**
* Returns the configuration needed to talk to the remote slave cluster.
* @param peerId a short that identifies the cluster
* @return the configuration for the peer cluster, null if it was unable to get the configuration
*/
Pair<ReplicationPeerConfig, Configuration> getPeerConf(String peerId) throws ReplicationException;
/**
* Update the peerConfig for the a given peer cluster
* @param id a short that identifies the cluster
* @param peerConfig new config for the peer cluster
* @throws ReplicationException
*/
void updatePeerConfig(String id, ReplicationPeerConfig peerConfig) throws ReplicationException;
}