wangxianghu commented on a change in pull request #2176: URL: https://github.com/apache/hudi/pull/2176#discussion_r519790365
########## File path: hudi-flink-writer/src/main/java/org/apache/hudi/operator/InstantGenerateOperator.java ########## @@ -0,0 +1,219 @@ +/* + * 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.hudi.operator; + +import org.apache.flink.api.common.state.ListState; +import org.apache.flink.api.common.state.ListStateDescriptor; +import org.apache.flink.runtime.state.StateInitializationContext; +import org.apache.flink.runtime.state.StateSnapshotContext; +import org.apache.flink.streaming.api.operators.AbstractStreamOperator; +import org.apache.flink.streaming.api.operators.OneInputStreamOperator; +import org.apache.flink.streaming.runtime.streamrecord.StreamRecord; +import org.apache.hadoop.conf.Configuration; +import org.apache.hadoop.fs.FileSystem; +import org.apache.hadoop.fs.Path; +import org.apache.hudi.HudiFlinkStreamer; +import org.apache.hudi.client.FlinkTaskContextSupplier; +import org.apache.hudi.client.HoodieFlinkWriteClient; +import org.apache.hudi.client.common.HoodieFlinkEngineContext; +import org.apache.hudi.client.common.TaskContextSupplier; +import org.apache.hudi.common.config.SerializableConfiguration; +import org.apache.hudi.common.fs.FSUtils; +import org.apache.hudi.common.model.HoodieRecord; +import org.apache.hudi.common.model.HoodieTableType; +import org.apache.hudi.common.table.HoodieTableMetaClient; +import org.apache.hudi.common.table.timeline.HoodieTimeline; +import org.apache.hudi.common.util.StringUtils; +import org.apache.hudi.util.StreamerUtil; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.io.IOException; +import java.util.ArrayList; +import java.util.Iterator; +import java.util.LinkedList; +import java.util.List; + +/** + * Operator helps to generate globally unique instant, it must be executed in one parallelism. Before generate a new + * instant , {@link InstantGenerateOperator} will always check whether the last instant has completed. if it is + * completed, a new instant will be generated immediately, otherwise, wait and check the state of last instant until + * time out and throw an exception. + */ +public class InstantGenerateOperator extends AbstractStreamOperator<HoodieRecord> implements OneInputStreamOperator<HoodieRecord, HoodieRecord> { + + private static final Logger LOG = LoggerFactory.getLogger(InstantGenerateOperator.class); + public static final String NAME = "InstantGenerateOperator"; + + private HudiFlinkStreamer.Config cfg; + private HoodieFlinkWriteClient writeClient; + private SerializableConfiguration serializableHadoopConf; + private transient FileSystem fs; + private String latestInstant = ""; + private List<String> latestInstantList = new ArrayList<>(1); + private transient ListState<String> latestInstantState; + private List<StreamRecord> bufferedRecords = new LinkedList(); + private transient ListState<StreamRecord> recordsState; + private Integer commitTimeout; + + @Override + public void processElement(StreamRecord<HoodieRecord> streamRecord) throws Exception { + if (streamRecord.getValue() != null) { + bufferedRecords.add(streamRecord); + output.collect(streamRecord); + } + } + + @Override + public void open() throws Exception { + super.open(); + // get configs from runtimeContext + cfg = (HudiFlinkStreamer.Config) getRuntimeContext().getExecutionConfig().getGlobalJobParameters(); + + // timeout + commitTimeout = Integer.valueOf(cfg.flinkCommitTimeout); + + // hadoopConf + serializableHadoopConf = new SerializableConfiguration(StreamerUtil.getHadoopConf()); + + // Hadoop FileSystem + fs = FSUtils.getFs(cfg.targetBasePath, serializableHadoopConf.get()); + + TaskContextSupplier taskContextSupplier = new FlinkTaskContextSupplier(null); + + // writeClient + writeClient = new HoodieFlinkWriteClient(new HoodieFlinkEngineContext(taskContextSupplier), StreamerUtil.getHoodieClientConfig(cfg)); + + // init table, create it if not exists. + initTable(); + } + + @Override + public void prepareSnapshotPreBarrier(long checkpointId) throws Exception { + super.prepareSnapshotPreBarrier(checkpointId); + // check whether the last instant is completed, if not, wait 10s and then throws an exception + if (!StringUtils.isNullOrEmpty(latestInstant)) { + doChecker(); + // last instant completed, set it empty + latestInstant = ""; + } + + // no data no new instant + if (!bufferedRecords.isEmpty()) { + latestInstant = startNewInstant(checkpointId); + } + } + + @Override + public void initializeState(StateInitializationContext context) throws Exception { + // instantState + ListStateDescriptor<String> latestInstantStateDescriptor = new ListStateDescriptor<String>("latestInstant", String.class); + latestInstantState = context.getOperatorStateStore().getListState(latestInstantStateDescriptor); + + // recordState + ListStateDescriptor<StreamRecord> recordsStateDescriptor = new ListStateDescriptor<StreamRecord>("recordsState", StreamRecord.class); + recordsState = context.getOperatorStateStore().getListState(recordsStateDescriptor); + + if (context.isRestored()) { + Iterator<String> latestInstantIterator = latestInstantState.get().iterator(); + latestInstantIterator.forEachRemaining(x -> latestInstant = x); + LOG.info("InstantGenerateOperator initializeState get latestInstant [{}]", latestInstant); + + Iterator<StreamRecord> recordIterator = recordsState.get().iterator(); + bufferedRecords.clear(); + recordIterator.forEachRemaining(x -> bufferedRecords.add(x)); + } + } + + @Override + public void snapshotState(StateSnapshotContext functionSnapshotContext) throws Exception { + if (latestInstantList.isEmpty()) { + latestInstantList.add(latestInstant); + } else { + latestInstantList.set(0, latestInstant); + } + latestInstantState.update(latestInstantList); + LOG.info("Update latest instant [{}]", latestInstant); + + recordsState.update(bufferedRecords); + LOG.info("Update records state size = [{}]", bufferedRecords.size()); + bufferedRecords.clear(); + } + + /** + * Create a new instant. + * + * @param checkpointId + */ + private String startNewInstant(long checkpointId) { + String newTime = writeClient.startCommit(); + LOG.info("create instant [{}], at checkpoint [{}]", newTime, checkpointId); + return newTime; + } + + /** + * Check the status of last instant. + */ + private void doChecker() throws InterruptedException { + // query the requested and inflight commit/deltacommit instants + String commitType = cfg.tableType.equals(HoodieTableType.COPY_ON_WRITE.name()) ? HoodieTimeline.COMMIT_ACTION : HoodieTimeline.DELTA_COMMIT_ACTION; + LOG.info("Query latest instant [{}]", latestInstant); + List<String> rollbackPendingCommits = writeClient.getInflightsAndRequestedInstants(commitType); + int tryTimes = 0; + while (tryTimes < commitTimeout) { + tryTimes++; + StringBuffer sb = new StringBuffer(); + if (rollbackPendingCommits.contains(latestInstant)) { + //清空 sb Review comment: > Chinese? Why this is a clear action to string buffer? my bad ---------------------------------------------------------------- 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: [email protected]
