anoopj commented on code in PR #15407: URL: https://github.com/apache/iceberg/pull/15407#discussion_r2844407313
########## delta-lake/src/main/java/org/apache/iceberg/delta/BaseSnapshotDeltaLakeKernelTableAction.java: ########## @@ -0,0 +1,418 @@ +/* + * 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.delta; + +import io.delta.kernel.Snapshot; +import io.delta.kernel.Table; +import io.delta.kernel.data.ColumnarBatch; +import io.delta.kernel.data.Row; +import io.delta.kernel.defaults.engine.DefaultEngine; +import io.delta.kernel.engine.Engine; +import io.delta.kernel.exceptions.TableNotFoundException; +import io.delta.kernel.internal.DeltaHistoryManager; +import io.delta.kernel.internal.DeltaLogActionUtils; +import io.delta.kernel.internal.SnapshotImpl; +import io.delta.kernel.internal.TableImpl; +import io.delta.kernel.internal.actions.AddFile; +import io.delta.kernel.internal.fs.Path; +import io.delta.kernel.internal.util.VectorUtils; +import io.delta.kernel.types.StructType; +import io.delta.kernel.utils.CloseableIterator; +import java.io.File; +import java.io.IOException; +import java.net.URI; +import java.net.URLDecoder; +import java.nio.charset.StandardCharsets; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.stream.Collectors; +import javax.annotation.Nonnull; +import org.apache.hadoop.conf.Configuration; +import org.apache.iceberg.AppendFiles; +import org.apache.iceberg.DataFile; +import org.apache.iceberg.DataFiles; +import org.apache.iceberg.FileFormat; +import org.apache.iceberg.ManageSnapshots; +import org.apache.iceberg.Metrics; +import org.apache.iceberg.MetricsConfig; +import org.apache.iceberg.PartitionField; +import org.apache.iceberg.PartitionSpec; +import org.apache.iceberg.Schema; +import org.apache.iceberg.TableProperties; +import org.apache.iceberg.Transaction; +import org.apache.iceberg.catalog.Catalog; +import org.apache.iceberg.catalog.TableIdentifier; +import org.apache.iceberg.exceptions.NotFoundException; +import org.apache.iceberg.hadoop.HadoopFileIO; +import org.apache.iceberg.io.InputFile; +import org.apache.iceberg.mapping.MappingUtil; +import org.apache.iceberg.mapping.NameMapping; +import org.apache.iceberg.mapping.NameMappingParser; +import org.apache.iceberg.parquet.ParquetUtil; +import org.apache.iceberg.relocated.com.google.common.base.Preconditions; +import org.apache.iceberg.relocated.com.google.common.collect.ImmutableMap; +import org.apache.iceberg.relocated.com.google.common.collect.Lists; +import org.apache.iceberg.types.Type; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +class BaseSnapshotDeltaLakeKernelTableAction implements SnapshotDeltaLakeTable { + private static final Logger LOG = + LoggerFactory.getLogger(BaseSnapshotDeltaLakeKernelTableAction.class); + + private static final String SNAPSHOT_SOURCE_PROP = "snapshot_source"; + private static final String DELTA_SOURCE_VALUE = "delta"; + private static final String ORIGINAL_LOCATION_PROP = "original_location"; + private static final String DELTA_VERSION_TAG_PREFIX = "delta-version-"; + private static final String DELTA_TIMESTAMP_TAG_PREFIX = "delta-ts-"; + + private final ImmutableMap.Builder<String, String> icebergPropertiesBuilder = + ImmutableMap.builder(); + + private final String deltaTableLocation; + private Engine deltaEngine; + private TableImpl deltaTable; + + private Catalog icebergCatalog; + private TableIdentifier newTableIdentifier; + private String newTableLocation; + private HadoopFileIO deltaLakeFileIO; + + BaseSnapshotDeltaLakeKernelTableAction(String deltaTableLocation) { + this.deltaTableLocation = deltaTableLocation; + this.newTableLocation = deltaTableLocation; + } + + @Override + public SnapshotDeltaLakeTable tableProperties(Map<String, String> properties) { + icebergPropertiesBuilder.putAll(properties); + return this; + } + + @Override + public SnapshotDeltaLakeTable tableProperty(String name, String value) { + icebergPropertiesBuilder.put(name, value); + return this; + } + + @Override + public SnapshotDeltaLakeTable tableLocation(String location) { + newTableLocation = location; + return this; + } + + @Override + public SnapshotDeltaLakeTable as(TableIdentifier identifier) { + newTableIdentifier = identifier; + return this; + } + + @Override + public SnapshotDeltaLakeTable icebergCatalog(Catalog catalog) { + icebergCatalog = catalog; + return this; + } + + @Override + public SnapshotDeltaLakeTable deltaLakeConfiguration(Configuration conf) { + deltaEngine = DefaultEngine.create(conf); + deltaLakeFileIO = new HadoopFileIO(conf); + deltaTable = (TableImpl) Table.forPath(deltaEngine, deltaTableLocation); + return this; + } + + @Override + public Result execute() { + Preconditions.checkArgument( + icebergCatalog != null && newTableIdentifier != null, + "Iceberg catalog and identifier cannot be null. Make sure to configure the action with a valid Iceberg catalog and identifier."); + Preconditions.checkArgument( + deltaTable != null && deltaLakeFileIO != null, + "Make sure to configure the action with a valid deltaLakeConfiguration"); + + long latestDeltaVersion = getLatestDeltaSnapshot().getVersion(); + long initialDeltaVersion = getEarliestDeltaLog(); + + // the initialDeltaVersion used as a lower bound and the actual snapshot can be at bigger + // version because of possible concurrent operations. It's ok. + SnapshotImpl initialDeltaSnapshot = getDeltaSnapshotAsOfVersion(initialDeltaVersion); + + LOG.info( + "Converting Delta Lake table at {} from version {} to version {} into Iceberg table {} ...", + deltaTableLocation, + initialDeltaVersion, + latestDeltaVersion, + newTableIdentifier); + + Schema icebergSchema = convertToIcebergSchema(initialDeltaSnapshot.getSchema()); Review Comment: This can cause silent data corruption if the table has column mapping enabled. For context, Delta Lake supports three column mapping modes: * `none`: Parquet files use the same column names as the logical schema. * `name`: Parquet files use physical names (UUIDs or opaque strings) that differ from the logical names The Delta log stores a mapping between them. This enables column renames without rewriting data files. * `id`: Similar to name mode but maps by field ID instead of name. Here we are mapping the schema based on the logical names. This won't work when column mapping is enabled (name or id). Delta Lake's UniForm feature requires column mapping to be enabled (name or id mode) and carries the physical-to-logical name mapping through to Iceberg via Iceberg's own column mapping (field IDs). For now, we should at least validate that column mapping is not enabled and fail fast: ``` Map<String, String> configuration = deltaSnapshot.getMetadata().getConfiguration(); String columnMappingMode = configuration.getOrDefault("delta.columnMapping.mode", "none"); if (!"none".equals(columnMappingMode)) { throw new UnsupportedOperationException("..."); } ``` -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
