meatballspaghetti commented on code in PR #5451: URL: https://github.com/apache/accumulo/pull/5451#discussion_r2047439616
########## core/src/main/java/org/apache/accumulo/core/util/tables/TableMapping.java: ########## @@ -0,0 +1,201 @@ +/* + * 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 + * + * https://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.accumulo.core.util.tables; + +import static java.util.Collections.emptySortedMap; +import static java.util.Objects.requireNonNull; +import static org.apache.accumulo.core.clientImpl.NamespaceMapping.deserializeMap; +import static org.apache.accumulo.core.clientImpl.NamespaceMapping.serializeMap; + +import java.util.Map; +import java.util.Objects; +import java.util.SortedMap; +import java.util.stream.Stream; + +import org.apache.accumulo.core.Constants; +import org.apache.accumulo.core.clientImpl.AcceptableThriftTableOperationException; +import org.apache.accumulo.core.clientImpl.ClientContext; +import org.apache.accumulo.core.clientImpl.Namespace; +import org.apache.accumulo.core.clientImpl.thrift.TableOperation; +import org.apache.accumulo.core.clientImpl.thrift.TableOperationExceptionType; +import org.apache.accumulo.core.data.NamespaceId; +import org.apache.accumulo.core.data.TableId; +import org.apache.accumulo.core.fate.zookeeper.ZooReaderWriter; +import org.apache.accumulo.core.metadata.AccumuloTable; +import org.apache.accumulo.core.zookeeper.ZcStat; +import org.apache.accumulo.core.zookeeper.ZooCache; +import org.apache.zookeeper.KeeperException; + +import com.google.common.collect.ImmutableSortedMap; + +public class TableMapping { + + private final ClientContext context; + private final NamespaceId namespaceId; + private volatile SortedMap<TableId,String> currentTableMap = emptySortedMap(); + private volatile SortedMap<String,TableId> currentTableReverseMap = emptySortedMap(); + private volatile long lastMzxid; + + public TableMapping(ClientContext context, NamespaceId namespaceId) { + this.context = context; + this.namespaceId = namespaceId; + } + + public void put(final ClientContext context, TableId tableId, String tableName, + TableOperation operation) + throws InterruptedException, KeeperException, AcceptableThriftTableOperationException { + var zoo = context.getZooSession().asReaderWriter(); + Stream.of(zoo, tableId, namespaceId, tableName).forEach(Objects::requireNonNull); + String zTableMapPath = getZTableMapPath(namespaceId); + if (!zoo.exists(zTableMapPath)) { + throw new KeeperException.NoNodeException(zTableMapPath + " does not exist in ZooKeeper"); + } + if (isBuiltInZKTable(tableId)) { + throw new AssertionError("Putting built-in tables in map should not be possible after init"); + } + zoo.mutateExisting(zTableMapPath, data -> { + var tables = deserializeMap(data); + final String currentName = tables.get(tableId.canonical()); + if (tableName.equals(currentName)) { + return null; // mapping already exists; operation is idempotent, so no change needed + } + if (currentName != null) { + throw new AcceptableThriftTableOperationException(null, tableId.canonical(), operation, + TableOperationExceptionType.EXISTS, "Table Id already exists"); + } + if (tables.containsValue(tableName)) { + throw new AcceptableThriftTableOperationException(null, tableId.canonical(), operation, + TableOperationExceptionType.EXISTS, "Table name already exists"); + } + tables.put(tableId.canonical(), tableName); + return serializeMap(tables); + }); + } + + public void remove(final ClientContext context, final TableId tableId) + throws InterruptedException, KeeperException, AcceptableThriftTableOperationException { + var zoo = context.getZooSession().asReaderWriter(); + Stream.of(zoo, tableId).forEach(Objects::requireNonNull); + if (isBuiltInZKTable(tableId)) { + throw new AssertionError("Removing built-in tables in map should not be possible"); + } + zoo.mutateExisting(getZTableMapPath(getNamespaceOfTableId(zoo, tableId)), data -> { + var tables = deserializeMap(data); + if (!tables.containsKey(tableId.canonical())) { + throw new AcceptableThriftTableOperationException(null, tableId.canonical(), + TableOperation.DELETE, TableOperationExceptionType.NOTFOUND, + "Table already removed while processing"); + } + tables.remove(tableId.canonical()); + return serializeMap(tables); + }); + } + + public void rename(final ClientContext context, final TableId tableId, final String oldName, + final String newName) + throws InterruptedException, KeeperException, AcceptableThriftTableOperationException { + var zoo = context.getZooSession().asReaderWriter(); + Stream.of(zoo, tableId, namespaceId, oldName, newName).forEach(Objects::requireNonNull); + String zTableMapPath = getZTableMapPath(namespaceId); + if (!zoo.exists(zTableMapPath)) { + throw new KeeperException.NoNodeException(zTableMapPath + " does not exist in ZooKeeper"); + } + if (isBuiltInZKTable(tableId)) { + throw new AssertionError("Renaming built-in tables in map should not be possible"); + } + zoo.mutateExisting(zTableMapPath, current -> { + var tables = deserializeMap(current); + final String currentName = tables.get(tableId.canonical()); + if (newName.equals(currentName)) { + return null; // assume in this case the operation is running again, so we are done + } + if (!oldName.equals(currentName)) { + throw new AcceptableThriftTableOperationException(null, oldName, TableOperation.RENAME, + TableOperationExceptionType.NOTFOUND, "Name changed while processing"); + } + if (tables.containsValue(newName)) { + throw new AcceptableThriftTableOperationException(null, newName, TableOperation.RENAME, + TableOperationExceptionType.EXISTS, "Table name already exists"); + } + tables.put(namespaceId.canonical(), newName); + return serializeMap(tables); + }); + } + + private synchronized void update(NamespaceId namespaceId) { + final ZooCache zc = context.getZooCache(); + final ZcStat stat = new ZcStat(); + final String zTableMapPath = getZTableMapPath(namespaceId); + + byte[] data = zc.get(zTableMapPath, stat); + if (stat.getMzxid() > lastMzxid) { + if (data == null) { + throw new IllegalStateException(zTableMapPath + " node should not be null"); Review Comment: To address this, [I just added](https://github.com/apache/accumulo/pull/5451/commits/42ada3e5251694d5b11f5cec88cbd47efacaa458) an `else if (data == null)` block after this that will clear the current table maps. If the `Mzxid` has changed (implying a cache change), and then the data is null, that would imply corruption. So I think `IllegalStateException` is still appropriate here. If the `Mzxid` has not changed, but `else if (data == null)` turns out to be true, that would imply the namespace was deleted and the cache did not update that. So in that case, I clear the maps as to reflect the namespace being deleted, which is legal. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
