StephanEwen commented on a change in pull request #13401: URL: https://github.com/apache/flink/pull/13401#discussion_r491728144
########## File path: flink-connectors/flink-connector-files/src/main/java/org/apache/flink/connector/file/src/impl/FileSourceSplitReader.java ########## @@ -0,0 +1,110 @@ +/* + * 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.flink.connector.file.src.impl; + +import org.apache.flink.configuration.Configuration; +import org.apache.flink.connector.base.source.reader.RecordsWithSplitIds; +import org.apache.flink.connector.base.source.reader.splitreader.SplitReader; +import org.apache.flink.connector.base.source.reader.splitreader.SplitsAddition; +import org.apache.flink.connector.base.source.reader.splitreader.SplitsChange; +import org.apache.flink.connector.file.src.FileSourceSplit; +import org.apache.flink.connector.file.src.reader.BulkFormat; +import org.apache.flink.connector.file.src.util.RecordAndPosition; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import javax.annotation.Nullable; + +import java.io.IOException; +import java.util.ArrayDeque; +import java.util.Queue; + +/** + * The {@link SplitReader} implementation for the file source. + */ +final class FileSourceSplitReader<T> implements SplitReader<RecordAndPosition<T>, FileSourceSplit> { + + private static final Logger LOG = LoggerFactory.getLogger(FileSourceSplitReader.class); + + private final Configuration config; + private final BulkFormat<T> readerFactory; + + private final Queue<FileSourceSplit> splits; + + @Nullable + private BulkFormat.Reader<T> currentReader; + @Nullable + private String currentSplitId; + + public FileSourceSplitReader(Configuration config, BulkFormat<T> readerFactory) { + this.config = config; + this.readerFactory = readerFactory; + this.splits = new ArrayDeque<>(); + } + + @Override + public RecordsWithSplitIds<RecordAndPosition<T>> fetch() throws IOException { + checkSplitOrStartNext(); + + final BulkFormat.RecordIterator<T> nextBatch = currentReader.readBatch(); + return nextBatch == null ? finishSplit() : FileRecords.forRecords(currentSplitId, nextBatch); + } + + @Override + public void handleSplitsChanges(final SplitsChange<FileSourceSplit> splitChange) { + if (!(splitChange instanceof SplitsAddition)) { + throw new UnsupportedOperationException(String.format( + "The SplitChange type of %s is not supported.", splitChange.getClass())); + } + + LOG.debug("Handling split change {}", splitChange); + splits.addAll(splitChange.splits()); + } + + @Override + public void wakeUp() {} + + private void checkSplitOrStartNext() throws IOException { + if (currentReader != null) { + return; + } + + final FileSourceSplit nextSplit = splits.poll(); + if (nextSplit == null) { + throw new IOException("Cannot fetch from another split - no split remaining"); + } + + currentSplitId = nextSplit.splitId(); + currentReader = nextSplit.skippedRecordCount() == 0 ? Review comment: This actually changed a bit in the latest fix, so I cannot apply the here suggested pattern any more. ---------------------------------------------------------------- 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: us...@infra.apache.org
