Jiabao-Sun commented on code in PR #1: URL: https://github.com/apache/flink-connector-mongodb/pull/1#discussion_r1032971595
########## flink-connector-mongodb/src/main/java/org/apache/flink/connector/mongodb/source/enumerator/splitter/MongoShardedSplitter.java: ########## @@ -0,0 +1,117 @@ +/* + * 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.mongodb.source.enumerator.splitter; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.connector.mongodb.source.split.MongoScanSourceSplit; +import org.apache.flink.util.FlinkRuntimeException; + +import com.mongodb.MongoException; +import com.mongodb.MongoNamespace; +import com.mongodb.client.MongoClient; +import org.bson.BsonDocument; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.util.ArrayList; +import java.util.Collection; +import java.util.List; +import java.util.Optional; + +import static org.apache.flink.connector.mongodb.common.utils.MongoConstants.KEY_FIELD; +import static org.apache.flink.connector.mongodb.common.utils.MongoConstants.MAX_FIELD; +import static org.apache.flink.connector.mongodb.common.utils.MongoConstants.MIN_FIELD; +import static org.apache.flink.connector.mongodb.common.utils.MongoUtils.isShardedCollectionDropped; +import static org.apache.flink.connector.mongodb.common.utils.MongoUtils.readChunks; +import static org.apache.flink.connector.mongodb.common.utils.MongoUtils.readCollectionMetadata; + +/** + * Sharded Partitioner + * + * <p>Uses the chunks collection and partitions the collection based on the sharded collections + * chunk ranges. + * + * <p>The following config collections' read privilege is required. + * + * <ul> + * <li>config.collections + * <li>config.chunks + * </ul> + */ +@Internal +public class MongoShardedSplitter { + + private static final Logger LOG = LoggerFactory.getLogger(MongoShardedSplitter.class); + + public static final MongoShardedSplitter INSTANCE = new MongoShardedSplitter(); + + private MongoShardedSplitter() {} + + public Collection<MongoScanSourceSplit> split(MongoSplitContext splitContext) { + MongoNamespace namespace = splitContext.getMongoNamespace(); + MongoClient mongoClient = splitContext.getMongoClient(); + + List<BsonDocument> chunks; + Optional<BsonDocument> collectionMetadata; + try { + collectionMetadata = readCollectionMetadata(mongoClient, namespace); + if (!collectionMetadata.isPresent()) { + LOG.error( + "Do sharded split failed, collection {} does not appear to be sharded.", + namespace); + throw new FlinkRuntimeException( + String.format( + "Do sharded split failed, %s is not a sharded collection.", + namespace)); + } + + if (isShardedCollectionDropped(collectionMetadata.get())) { + LOG.error("Do sharded split failed, collection {} was dropped.", namespace); + throw new FlinkRuntimeException( + String.format("Do sharded split failed, %s was dropped.", namespace)); + } + + chunks = readChunks(mongoClient, collectionMetadata.get()); + if (chunks.isEmpty()) { + LOG.error("Do sharded split failed, chunks of {} is empty.", namespace); + throw new FlinkRuntimeException( + String.format( + "Do sharded split failed, chunks of %s is empty.", namespace)); + } + } catch (MongoException e) { + LOG.error( + "Read chunks from {} failed with error message: {}", namespace, e.getMessage()); + throw new FlinkRuntimeException(e); + } + + List<MongoScanSourceSplit> sourceSplits = new ArrayList<>(chunks.size()); + for (int i = 0; i < chunks.size(); i++) { + BsonDocument chunk = chunks.get(i); + sourceSplits.add( + new MongoScanSourceSplit( + String.format("%s_%d", namespace, i), Review Comment: How about we use the primary key (`_id` field mentioned above) of `config.chunks`? -- 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
