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* 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.
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package org.apache.solr.cloud;
import java.lang.invoke.MethodHandles;
import java.net.URI;
import java.time.Instant;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
import java.util.Properties;
import org.apache.lucene.util.Version;
import org.apache.solr.common.SolrException;
import org.apache.solr.common.SolrException.ErrorCode;
import org.apache.solr.common.cloud.ClusterState;
import org.apache.solr.common.cloud.DocCollection;
import org.apache.solr.common.cloud.Replica;
import org.apache.solr.common.cloud.Replica.State;
import org.apache.solr.common.cloud.Slice;
import org.apache.solr.common.cloud.SolrZkClient;
import org.apache.solr.common.cloud.ZkNodeProps;
import org.apache.solr.common.params.CollectionAdminParams;
import org.apache.solr.common.params.CoreAdminParams;
import org.apache.solr.common.params.ModifiableSolrParams;
import org.apache.solr.common.util.NamedList;
import org.apache.solr.core.CoreContainer;
import org.apache.solr.core.backup.BackupManager;
import org.apache.solr.core.backup.repository.BackupRepository;
import org.apache.solr.core.snapshots.CollectionSnapshotMetaData;
import org.apache.solr.core.snapshots.CollectionSnapshotMetaData.CoreSnapshotMetaData;
import org.apache.solr.core.snapshots.CollectionSnapshotMetaData.SnapshotStatus;
import org.apache.solr.core.snapshots.SolrSnapshotManager;
import org.apache.solr.handler.component.ShardHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static org.apache.solr.cloud.OverseerCollectionMessageHandler.COLL_CONF;
import static org.apache.solr.common.cloud.ZkStateReader.COLLECTION_PROP;
import static org.apache.solr.common.cloud.ZkStateReader.CORE_NAME_PROP;
import static org.apache.solr.common.params.CommonAdminParams.ASYNC;
import static org.apache.solr.common.params.CommonParams.NAME;
public class BackupCmd implements OverseerCollectionMessageHandler.Cmd {
private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
private final OverseerCollectionMessageHandler ocmh;
public BackupCmd(OverseerCollectionMessageHandler ocmh) {
this.ocmh = ocmh;
}
@Override
public void call(ClusterState state, ZkNodeProps message, NamedList results) throws Exception {
String collectionName = message.getStr(COLLECTION_PROP);
String backupName = message.getStr(NAME);
String repo = message.getStr(CoreAdminParams.BACKUP_REPOSITORY);
Instant startTime = Instant.now();
CoreContainer cc = ocmh.overseer.getZkController().getCoreContainer();
BackupRepository repository = cc.newBackupRepository(Optional.ofNullable(repo));
BackupManager backupMgr = new BackupManager(repository, ocmh.zkStateReader);
// Backup location
URI location = repository.createURI(message.getStr(CoreAdminParams.BACKUP_LOCATION));
URI backupPath = repository.resolve(location, backupName);
//Validating if the directory already exists.
if (repository.exists(backupPath)) {
throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "The backup directory already exists: " + backupPath);
}
// Create a directory to store backup details.
repository.createDirectory(backupPath);
String strategy = message.getStr(CollectionAdminParams.INDEX_BACKUP_STRATEGY, CollectionAdminParams.COPY_FILES_STRATEGY);
switch (strategy) {
case CollectionAdminParams.COPY_FILES_STRATEGY: {
copyIndexFiles(backupPath, message, results);
break;
}
case CollectionAdminParams.NO_INDEX_BACKUP_STRATEGY: {
break;
}
}
log.info("Starting to backup ZK data for backupName={}", backupName);
//Download the configs
String configName = ocmh.zkStateReader.readConfigName(collectionName);
backupMgr.downloadConfigDir(location, backupName, configName);
//Save the collection's state. Can be part of the monolithic clusterstate.json or a individual state.json
//Since we don't want to distinguish we extract the state and back it up as a separate json
DocCollection collectionState = ocmh.zkStateReader.getClusterState().getCollection(collectionName);
backupMgr.writeCollectionState(location, backupName, collectionName, collectionState);
Properties properties = new Properties();
properties.put(BackupManager.BACKUP_NAME_PROP, backupName);
properties.put(BackupManager.COLLECTION_NAME_PROP, collectionName);
properties.put(COLL_CONF, configName);
properties.put(BackupManager.START_TIME_PROP, startTime.toString());
properties.put(BackupManager.INDEX_VERSION_PROP, Version.LATEST.toString());
//TODO: Add MD5 of the configset. If during restore the same name configset exists then we can compare checksums to see if they are the same.
//if they are not the same then we can throw an error or have an 'overwriteConfig' flag
//TODO save numDocs for the shardLeader. We can use it to sanity check the restore.
backupMgr.writeBackupProperties(location, backupName, properties);
log.info("Completed backing up ZK data for backupName={}", backupName);
}
private Replica selectReplicaWithSnapshot(CollectionSnapshotMetaData snapshotMeta, Slice slice) {
// The goal here is to choose the snapshot of the replica which was the leader at the time snapshot was created.
// If that is not possible, we choose any other replica for the given shard.
Collection<CoreSnapshotMetaData> snapshots = snapshotMeta.getReplicaSnapshotsForShard(slice.getName());
Optional<CoreSnapshotMetaData> leaderCore = snapshots.stream().filter(x -> x.isLeader()).findFirst();
if (leaderCore.isPresent()) {
log.info("Replica {} was the leader when snapshot {} was created.", leaderCore.get().getCoreName(), snapshotMeta.getName());
Replica r = slice.getReplica(leaderCore.get().getCoreName());
if ((r != null) && !r.getState().equals(State.DOWN)) {
return r;
}
}
Optional<Replica> r = slice.getReplicas().stream()
.filter(x -> x.getState() != State.DOWN && snapshotMeta.isSnapshotExists(slice.getName(), x))
.findFirst();
if (!r.isPresent()) {
throw new SolrException(ErrorCode.SERVER_ERROR,
"Unable to find any live replica with a snapshot named " + snapshotMeta.getName() + " for shard " + slice.getName());
}
return r.get();
}
private void copyIndexFiles(URI backupPath, ZkNodeProps request, NamedList results) throws Exception {
String collectionName = request.getStr(COLLECTION_PROP);
String backupName = request.getStr(NAME);
String asyncId = request.getStr(ASYNC);
String repoName = request.getStr(CoreAdminParams.BACKUP_REPOSITORY);
ShardHandler shardHandler = ocmh.shardHandlerFactory.getShardHandler();
Map<String, String> requestMap = new HashMap<>();
String commitName = request.getStr(CoreAdminParams.COMMIT_NAME);
Optional<CollectionSnapshotMetaData> snapshotMeta = Optional.empty();
if (commitName != null) {
SolrZkClient zkClient = ocmh.overseer.getZkController().getZkClient();
snapshotMeta = SolrSnapshotManager.getCollectionLevelSnapshot(zkClient, collectionName, commitName);
if (!snapshotMeta.isPresent()) {
throw new SolrException(ErrorCode.BAD_REQUEST, "Snapshot with name " + commitName
+ " does not exist for collection " + collectionName);
}
if (snapshotMeta.get().getStatus() != SnapshotStatus.Successful) {
throw new SolrException(ErrorCode.BAD_REQUEST, "Snapshot with name " + commitName + " for collection " + collectionName
+ " has not completed successfully. The status is " + snapshotMeta.get().getStatus());
}
}
log.info("Starting backup of collection={} with backupName={} at location={}", collectionName, backupName,
backupPath);
Collection<String> shardsToConsider = Collections.emptySet();
if (snapshotMeta.isPresent()) {
shardsToConsider = snapshotMeta.get().getShards();
}
for (Slice slice : ocmh.zkStateReader.getClusterState().getCollection(collectionName).getActiveSlices()) {
Replica replica = null;
if (snapshotMeta.isPresent()) {
if (!shardsToConsider.contains(slice.getName())) {
log.warn("Skipping the backup for shard {} since it wasn't part of the collection {} when snapshot {} was created.",
slice.getName(), collectionName, snapshotMeta.get().getName());
continue;
}
replica = selectReplicaWithSnapshot(snapshotMeta.get(), slice);
} else {
// Note - Actually this can return a null value when there is no leader for this shard.
replica = slice.getLeader();
if (replica == null) {
throw new SolrException(ErrorCode.SERVER_ERROR, "No 'leader' replica available for shard " + slice.getName() + " of collection " + collectionName);
}
}
String coreName = replica.getStr(CORE_NAME_PROP);
ModifiableSolrParams params = new ModifiableSolrParams();
params.set(CoreAdminParams.ACTION, CoreAdminParams.CoreAdminAction.BACKUPCORE.toString());
params.set(NAME, slice.getName());
params.set(CoreAdminParams.BACKUP_REPOSITORY, repoName);
params.set(CoreAdminParams.BACKUP_LOCATION, backupPath.toASCIIString()); // note: index dir will be here then the "snapshot." + slice name
params.set(CORE_NAME_PROP, coreName);
if (snapshotMeta.isPresent()) {
params.set(CoreAdminParams.COMMIT_NAME, snapshotMeta.get().getName());
}
ocmh.sendShardRequest(replica.getNodeName(), params, shardHandler, asyncId, requestMap);
log.debug("Sent backup request to core={} for backupName={}", coreName, backupName);
}
log.debug("Sent backup requests to all shard leaders for backupName={}", backupName);
ocmh.processResponses(results, shardHandler, true, "Could not backup all replicas", asyncId, requestMap);
}
}