omalley commented on a change in pull request #1495: URL: https://github.com/apache/iceberg/pull/1495#discussion_r497077327
########## File path: mr/src/main/java/org/apache/iceberg/mr/hive/HiveIcebergMetaHook.java ########## @@ -0,0 +1,161 @@ +/* + * 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.iceberg.mr.hive; + +import java.util.HashSet; +import java.util.Properties; +import java.util.Set; +import java.util.stream.Collectors; +import java.util.stream.Stream; +import org.apache.hadoop.conf.Configuration; +import org.apache.hadoop.hive.metastore.HiveMetaHook; +import org.apache.hadoop.hive.metastore.api.MetaException; +import org.apache.iceberg.BaseMetastoreTableOperations; +import org.apache.iceberg.PartitionSpecParser; +import org.apache.iceberg.Schema; +import org.apache.iceberg.SchemaParser; +import org.apache.iceberg.Table; +import org.apache.iceberg.exceptions.NoSuchTableException; +import org.apache.iceberg.hive.HiveTableOperations; +import org.apache.iceberg.mr.Catalogs; +import org.apache.iceberg.mr.InputFormatConfig; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +public class HiveIcebergMetaHook implements HiveMetaHook { + private static final Logger LOG = LoggerFactory.getLogger(HiveIcebergMetaHook.class); + private static final Set<String> PARAMETERS_TO_REMOVE = Stream + .of(InputFormatConfig.TABLE_SCHEMA, InputFormatConfig.PARTITION_SPEC, Catalogs.LOCATION, Catalogs.NAME) + .collect(Collectors.toCollection(HashSet::new)); + private static final Set<String> PROPERTIES_TO_REMOVE = Stream + .of(InputFormatConfig.HIVE_DELETE_BACKING_TABLE, "storage_handler", "EXTERNAL") + .collect(Collectors.toCollection(HashSet::new)); + + private final Configuration conf; + private Table icebergTable = null; + private Properties catalogProperties; + private boolean deleteIcebergTable; + + public HiveIcebergMetaHook(Configuration conf) { + this.conf = conf; + } + + @Override + public void preCreateTable(org.apache.hadoop.hive.metastore.api.Table hmsTable) { + catalogProperties = getCatalogProperties(hmsTable); + try { + icebergTable = Catalogs.loadTable(conf, catalogProperties); + + Preconditions.checkArgument(catalogProperties.getProperty(InputFormatConfig.TABLE_SCHEMA) == null, + "Iceberg table already created - can not use provided schema"); + Preconditions.checkArgument(catalogProperties.getProperty(InputFormatConfig.PARTITION_SPEC) == null, + "Iceberg table already created - can not use provided partition specification"); + + LOG.info("Iceberg table already exists {}", icebergTable); + } catch (NoSuchTableException nte) { + String schemaString = catalogProperties.getProperty(InputFormatConfig.TABLE_SCHEMA); + Preconditions.checkNotNull(schemaString, "Please provide a table schema"); + // Just check if it is parsable, and later use for partition specification parsing + Schema schema = SchemaParser.fromJson(schemaString); + + String specString = catalogProperties.getProperty(InputFormatConfig.PARTITION_SPEC); + if (specString != null) { + // Just check if it is parsable + PartitionSpecParser.fromJson(schema, schemaString); + } + + // Allow purging table data if the table is created now and not set otherwise + if (hmsTable.getParameters().get(InputFormatConfig.HIVE_DELETE_BACKING_TABLE) == null) { + hmsTable.getParameters().put(InputFormatConfig.HIVE_DELETE_BACKING_TABLE, "TRUE"); Review comment: Since managed means that it is hive-owned and in hive acid layout, it doesn't seem like we should have iceberg tables that hive thinks are managed. It doesn't seem like we should have a separate property for deleting the external table's data and should just use the **external.table.purge** table property that Hive already uses. It probably makes sense to also delete the data when: - We are using the HiveCatalog. - The iceberg location property is set. since once the Hive metadata is deleted, it won't be recoverable. Rather than having separate logic, it might make sense to have the HiveCatalog set that property when it creates a table. ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
