echauchot commented on code in PR #3: URL: https://github.com/apache/flink-connector-cassandra/pull/3#discussion_r1101701294
########## flink-connector-cassandra/src/main/java/org/apache/flink/connector/cassandra/source/split/CassandraSplitState.java: ########## @@ -0,0 +1,66 @@ +/* + * 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.cassandra.source.split; + +import com.datastax.driver.core.ResultSet; + +import javax.annotation.Nullable; + +import java.math.BigInteger; + +/** + * Mutable {@link CassandraSplit} that keeps track of the reading process of the associated split. + */ +public class CassandraSplitState { + private final CassandraSplit cassandraSplit; + // Cassandra ResultSet is paginated, a new page is read only if all the records of the previous + // one were consumed. fetch() can be interrupted so we use the resultSet to keep track of the + // reading process. + // It is null when reading has not started (before fetch is called on the split). + @Nullable private ResultSet resultSet; Review Comment: As discussed in the other comment ResultSet is just a handle so the status of the read will not be part of the checkpoint leading to a re-read of the already output data indeed. The only way is to manage the memory size of the split at the enumerator level and either output all the split or not a all. That way in case of interrupted fetch nothing will be output and the split could be read again from the beginning after recovery leading to no duplicates. -- 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: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
