Apache Hudi初探(九)(与spark的结合)--非bulk_insert模式

背景

之前讨论的都是’hoodie.datasource.write.operation’:'bulk_insert’的前提下,在这种模式下,是没有json文件的已形成如下的文件:

/dt=1/.hoodie_partition_metadata
/dt=1/2ffe3579-6ddb-4c5f-bf03-5c1b5dfce0a0-0_0-41263-0_20230528233336713.parquet
/dt=1/30b7d5b2-12e8-415a-8ec5-18206fe601c0-0_0-22102-0_20230528231643200.parquet
/dt=1/4abc1c6d-a8aa-4c15-affc-61a35171ce69-0_4-22106-0_20230528231643200.parquet
/dt=1/513dee80-2e8c-4db8-baee-a767b9dba41c-0_2-22104-0_20230528231643200.parquet
/dt=1/57076f86-0a62-4f52-8b50-31a5f769b26a-0_1-22103-0_20230528231643200.parquet
/dt=1/84553727-be9d-4273-bad9-0a38d9240815-0_0-59818-0_20230528233513387.parquet
/dt=1/fecd6a84-9a74-40b1-bfc1-13612a67a785-0_0-26640-0_20230528231723951.parquet

因为是bulk insert操作,所以没有去重的需要,所以直接采用spark原生的方式,
以下我们讨论非spark原生的方式,

闲说杂谈

继续Apache Hudi初探(八)(与spark的结合)–非bulk_insert模式
剩下的代码:

   val writeResult = DataSourceUtils.doWriteOperation(client, hoodieRecords, instantTime, operation)
   val (writeSuccessful, compactionInstant, clusteringInstant) =
        commitAndPerformPostOperations(sqlContext.sparkSession, df.schema,
          writeResult, parameters, writeClient, tableConfig, jsc,
          TableInstantInfo(basePath, instantTime, commitActionType, operation))
  • doWriteOperation 最终调用的是SparkRDDWriteClient对应的方法,如bulkInsert/insert/upsert/insertOverwrite,这里我们以upsert为例:

     public JavaRDD<WriteStatus> upsert(JavaRDD<HoodieRecord<T>> records, String instantTime) {
      HoodieTable<T, HoodieData<HoodieRecord<T>>, HoodieData<HoodieKey>, HoodieData<WriteStatus>> table =
          initTable(WriteOperationType.UPSERT, Option.ofNullable(instantTime));
      table.validateUpsertSchema();
      preWrite(instantTime, WriteOperationType.UPSERT, table.getMetaClient());
      HoodieWriteMetadata<HoodieData<WriteStatus>> result = table.upsert(context, instantTime, HoodieJavaRDD.of(records));
      HoodieWriteMetadata<JavaRDD<WriteStatus>> resultRDD = result.clone(HoodieJavaRDD.getJavaRDD(result.getWriteStatuses()));
      if (result.getIndexLookupDuration().isPresent()) {
        metrics.updateIndexMetrics(LOOKUP_STR, result.getIndexLookupDuration().get().toMillis());
      }
      return postWrite(resultRDD, instantTime, table);
    }
    
    • initTable 创建获取一个HoodieSparkMergeOnReadTable

    • validateSchema 校验Schema的兼容性

    • preWrite 写之前的操作,这个之前有说过,具体参考:Apache Hudi初探(五)(与spark的结合)

    • table.upsert 真正写入数据的操作
      最终调用的是 SparkInsertDeltaCommitActionExecutor<>().execute() 方法,最后最调用到HoodieWriteHelper.write

        public HoodieWriteMetadata<O> write(String instantTime,
                                        I inputRecords,
                                        HoodieEngineContext context,
                                        HoodieTable<T, I, K, O> table,
                                        boolean shouldCombine,
                                        int shuffleParallelism,
                                        BaseCommitActionExecutor<T, I, K, O, R> executor,
                                        WriteOperationType operationType) {
          try {
              // De-dupe/merge if needed
              I dedupedRecords =
                  combineOnCondition(shouldCombine, inputRecords, shuffleParallelism, table);
      
              Instant lookupBegin = Instant.now();
              I taggedRecords = dedupedRecords;
              if (table.getIndex().requiresTagging(operationType)) {
                // perform index loop up to get existing location of records
                context.setJobStatus(this.getClass().getSimpleName(), "Tagging: " + table.getConfig().getTableName());
                taggedRecords = tag(dedupedRecords, context, table);
              }
              Duration indexLookupDuration = Duration.between(lookupBegin, Instant.now());
      
              HoodieWriteMetadata<O> result = executor.execute(taggedRecords);
              result.setIndexLookupDuration(indexLookupDuration);
              return result;
            } catch (Throwable e) {
              if (e instanceof HoodieUpsertException) {
                throw (HoodieUpsertException) e;
              }
              throw new HoodieUpsertException("Failed to upsert for commit time " + instantTime, e);
            }
          }
      
      • combineOnCondition 数据去重
        最终是调用HoodieRecordPayload.preCombine(默认是OverwriteWithLatestAvroPayload.preCombine
      • taggedRecords = tag(dedupedRecords, context, table) 因为默认的indexHoodieSimpleIndex,所以这个时候会调用到打标记这个操作
        最终调用到的是HoodieSimpleIndextagLocationInternal,此时获得的是带有location的记录(如果没有索引到,则 record中的locationnull
      • executor.execute(taggedRecords) 该方法最终调用到BaseSparkCommitActionExecutor.execute方法:
        public HoodieWriteMetadata<HoodieData<WriteStatus>> execute(HoodieData<HoodieRecord<T>> inputRecords) {
           // Cache the tagged records, so we don't end up computing both
           // TODO: Consistent contract in HoodieWriteClient regarding preppedRecord storage level handling
           JavaRDD<HoodieRecord<T>> inputRDD = HoodieJavaRDD.getJavaRDD(inputRecords);
           if (inputRDD.getStorageLevel() == StorageLevel.NONE()) {
             inputRDD.persist(StorageLevel.MEMORY_AND_DISK_SER());
           } else {
             LOG.info("RDD PreppedRecords was persisted at: " + inputRDD.getStorageLevel());
           }
        
           WorkloadProfile workloadProfile = null;
           if (isWorkloadProfileNeeded()) {
             context.setJobStatus(this.getClass().getSimpleName(), "Building workload profile: " + config.getTableName());
             workloadProfile = new WorkloadProfile(buildProfile(inputRecords), operationType, table.getIndex().canIndexLogFiles());
             LOG.info("Input workload profile :" + workloadProfile);
           }
        
           // partition using the insert partitioner
           final Partitioner partitioner = getPartitioner(workloadProfile);
           if (isWorkloadProfileNeeded()) {
             saveWorkloadProfileMetadataToInflight(workloadProfile, instantTime);
           }
        
           // handle records update with clustering
           Set<HoodieFileGroupId> fileGroupsInPendingClustering =
               table.getFileSystemView().getFileGroupsInPendingClustering().map(Pair::getKey).collect(Collectors.toSet());
           HoodieData<HoodieRecord<T>> inputRecordsWithClusteringUpdate = fileGroupsInPendingClustering.isEmpty() ? inputRecords : clusteringHandleUpdate(inputRecords, fileGroupsInPendingClustering);
        
           context.setJobStatus(this.getClass().getSimpleName(), "Doing partition and writing data: " + config.getTableName());
           HoodieData<WriteStatus> writeStatuses = mapPartitionsAsRDD(inputRecordsWithClusteringUpdate, partitioner);
           HoodieWriteMetadata<HoodieData<WriteStatus>> result = new HoodieWriteMetadata<>();
           updateIndexAndCommitIfNeeded(writeStatuses, result);
           return result;
         }
        
        • inputRDD.persist持久化当前的RDD,因为该RDD会被使用多次,便于加速

        • workloadProfile = new WorkloadProfile(buildProfile(inputRecords)
          构建一个状态信息,主要是记录一下插入的记录数量和更新的记录数量 其中主要形成了以filedId为key, *Pair<instantTime,count>*为value的Map数据

        • final Partitioner partitioner = getPartitioner(workloadProfile) 这里针对于upsert操作会返回UpsertPartitioner(因为默认hoodie.storage.layout.typeDEFAULT),
          其中该UpsertPartitioner实例的构造方法中会进行一些额外的操作 assignUpdatesassignInserts(这里暂时忽略),主要是对数据进行分区处理,设计到小文件的处理

        • mapPartitionsAsRDD(inputRecordsWithClusteringUpdate, partitioner)
          这里会根据hoodie.table.base.file.format的值(默认是parquet),如果是hfile,则会要求排序,如果没有则只是按照partitioner进行重分区,
          之后再进行数据insert或者update,具体的方法为handleUpsertPartition,会根据之前的partitoner信息进行插入或者更新(里面的细节有点复杂)

        • updateIndexAndCommitIfNeeded(writeStatuses, result)
          该操作会首先会更新索引信息,对于HoodieSimpleIndex来说,什么也不操作(因为该index每次都会从parquet文件中读取信息从而组装成index),
          其次如果hoodie.auto.committrue(默认是true)会进行元数据的commit操作

    • postWrite 这里的postCommit 进行自动clean和Archive操作

  • commitAndPerformPostOperations
    这里主要是异步Compcation和Clustering以及同步hive元数据,类似Apache Hudi初探(七)(与spark的结合)

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转载自blog.csdn.net/monkeyboy_tech/article/details/131137785
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