vaibhavk1992 commented on code in PR #729: URL: https://github.com/apache/incubator-xtable/pull/729#discussion_r2582267216
########## xtable-core/src/main/java/org/apache/xtable/kernel/DeltaKernelDataFileExtractor.java: ########## @@ -0,0 +1,190 @@ +/* + * 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.xtable.kernel; + +import java.util.List; +import java.util.Map; +import java.util.stream.Collectors; + +import lombok.Builder; + +import io.delta.kernel.Snapshot; +import io.delta.kernel.Table; +import io.delta.kernel.data.FilteredColumnarBatch; +import io.delta.kernel.data.Row; +import io.delta.kernel.engine.Engine; +import io.delta.kernel.internal.InternalScanFileUtils; +import io.delta.kernel.internal.ScanImpl; +import io.delta.kernel.internal.SnapshotImpl; +import io.delta.kernel.internal.actions.AddFile; +import io.delta.kernel.types.StructField; +import io.delta.kernel.types.StructType; +import io.delta.kernel.utils.CloseableIterator; + +import org.apache.xtable.model.schema.InternalField; +import org.apache.xtable.model.schema.InternalPartitionField; +import org.apache.xtable.model.schema.InternalSchema; +import org.apache.xtable.model.storage.FileFormat; +import org.apache.xtable.model.storage.InternalDataFile; +import org.apache.xtable.spi.extractor.DataFileIterator; + +/** DeltaDataFileExtractor lets the consumer iterate over partitions. */ +@Builder +public class DeltaKernelDataFileExtractor { + + @Builder.Default + private final DeltaKernelPartitionExtractor partitionExtractor = + DeltaKernelPartitionExtractor.getInstance(); + + @Builder.Default + private final DeltaKernelStatsExtractor fileStatsExtractor = + DeltaKernelStatsExtractor.getInstance(); + + @Builder.Default + private final DeltaKernelActionsConverter actionsConverter = + DeltaKernelActionsConverter.getInstance(); + + private final String basePath; + + /** + * Initializes an iterator for Delta Lake files. + * + * @return Delta table file iterator + */ + public DataFileIterator iterator( + Snapshot deltaSnapshot, Table table, Engine engine, InternalSchema schema) { + return new DeltaDataFileIterator(deltaSnapshot, table, engine, schema, true); + } + + public class DeltaDataFileIterator implements DataFileIterator { + private final CloseableIterator<FilteredColumnarBatch> scanFiles; + private final FileFormat fileFormat; + private final Table table; + private final List<InternalField> fields; + private final List<InternalPartitionField> partitionFields; + private final boolean includeColumnStats; + + private CloseableIterator<Row> currentFileRows; + private InternalDataFile nextFile; + + private DeltaDataFileIterator( + Snapshot snapshot, + Table table, + Engine engine, + InternalSchema schema, + boolean includeColumnStats) { + this.includeColumnStats = includeColumnStats; + this.table = table; + this.fields = schema.getFields(); + String provider = ((SnapshotImpl) snapshot).getMetadata().getFormat().getProvider(); + this.fileFormat = actionsConverter.convertToFileFormat(provider); + + StructType fullSchema = snapshot.getSchema(); // The full table schema + List<String> partitionColumns = snapshot.getPartitionColumnNames(); + + List<StructField> partitionFieldsStr = + fullSchema.fields().stream() + .filter(field -> partitionColumns.contains(field.getName())) + .collect(Collectors.toList()); + + StructType partitionSchema = new StructType(partitionFieldsStr); + + this.partitionFields = + partitionExtractor.convertFromDeltaPartitionFormat(schema, partitionSchema); + + ScanImpl myScan = (ScanImpl) snapshot.getScanBuilder().build(); + this.scanFiles = myScan.getScanFiles(engine, includeColumnStats); + + // Initialize first element + this.nextFile = computeNext(); + } + + @Override + public void close() throws Exception { + try { + if (currentFileRows != null) { + currentFileRows.close(); + } + } finally { + scanFiles.close(); + } + } + + @Override + public boolean hasNext() { + return nextFile != null; + } + + @Override + public InternalDataFile next() { + InternalDataFile current = nextFile; + nextFile = computeNext(); + return current; + } + + private InternalDataFile computeNext() { + try { + while (true) { Review Comment: fixed the code and removed the while true condition. -- 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]
