rdblue commented on a change in pull request #2945: URL: https://github.com/apache/iceberg/pull/2945#discussion_r711403612
########## File path: core/src/main/java/org/apache/iceberg/io/CDCWriter.java ########## @@ -0,0 +1,135 @@ +/* + * 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.io; + +import java.io.IOException; +import java.util.Map; +import java.util.function.Function; +import org.apache.iceberg.PartitionSpec; +import org.apache.iceberg.Schema; +import org.apache.iceberg.StructLike; +import org.apache.iceberg.deletes.PositionDelete; +import org.apache.iceberg.util.StructLikeMap; +import org.apache.iceberg.util.StructProjection; + +public class CDCWriter<T> extends BaseDeltaWriter<T> { + + private final FanoutDataWriter<T> dataWriter; + private final PartitionAwareFileWriter<T, DeleteWriteResult> equalityDeleteWriter; + private final PartitionAwareFileWriter<PositionDelete<T>, DeleteWriteResult> positionDeleteWriter; + private final StructProjection keyProjection; + private final Map<StructLike, PartitionAwarePathOffset> insertedRows; + private final PositionDelete<T> positionDelete; + private final Function<T, StructLike> toStructLike; + + public CDCWriter(FanoutDataWriter<T> dataWriter, + PartitionAwareFileWriter<T, DeleteWriteResult> equalityDeleteWriter, + PartitionAwareFileWriter<PositionDelete<T>, DeleteWriteResult> positionDeleteWriter, + Schema schema, Schema deleteSchema, Function<T, StructLike> toStructLike) { + this.dataWriter = dataWriter; + this.equalityDeleteWriter = equalityDeleteWriter; + this.positionDeleteWriter = positionDeleteWriter; + this.positionDelete = new PositionDelete<>(); + this.keyProjection = StructProjection.create(schema, deleteSchema); + this.insertedRows = StructLikeMap.create(deleteSchema.asStruct()); + this.toStructLike = toStructLike; + } + + @Override + public void insert(T row, PartitionSpec spec, StructLike partition) throws IOException { + CharSequence currentPath = dataWriter.currentPath(spec, partition); + long currentPosition = dataWriter.currentPosition(spec, partition); + PartitionAwarePathOffset offset = new PartitionAwarePathOffset(spec, partition, currentPath, currentPosition); + + StructLike copiedKey = StructCopy.copy(keyProjection.wrap(toStructLike.apply(row))); + + PartitionAwarePathOffset previous = insertedRows.put(copiedKey, offset); + if (previous != null) { + // TODO: attach the previous row if has a position delete row schema + positionDelete.set(previous.path(), previous.rowOffset(), null); + positionDeleteWriter.write(positionDelete, spec, partition); + } + + dataWriter.write(row, spec, partition); + } + + @Override + public void delete(T row, PartitionSpec spec, StructLike partition) throws IOException { Review comment: I think we need to clearly document that this assumes that the row to delete has the same schema as the rows that will be inserted. We could also have a `directDelete` method that passes just the equality delete columns (key). That's worth considering if you want to split the interface for equality and position delete use cases. -- 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]
