[HUDI-4760] Fixing repeated trigger of data file creations w/ clustering

hudi-client/hudi-client-common/src/main/java/org/apache/hudi/table/action/commit/BaseCommitActionExecutor.java

@@ -166,7 +166,7 @@ protected void runPrecommitValidators(HoodieWriteMetadata<O> writeMetadata) {
     }
     throw new HoodieIOException("Precommit validation not implemented for all engines yet");
   }
-  
+
   protected void commitOnAutoCommit(HoodieWriteMetadata result) {
     // validate commit action before committing result
     runPrecommitValidators(result);
@@ -249,7 +249,7 @@ protected HoodieWriteMetadata<HoodieData<WriteStatus>> executeClustering(HoodieC
     HoodieData<WriteStatus> statuses = updateIndex(writeStatusList, writeMetadata);
     writeMetadata.setWriteStats(statuses.map(WriteStatus::getStat).collectAsList());
     writeMetadata.setPartitionToReplaceFileIds(getPartitionToReplacedFileIds(clusteringPlan, writeMetadata));
-    validateWriteResult(clusteringPlan, writeMetadata);
+    // if we don't cache the write statuses above, validation will call isEmpty which might retrigger the execution again.
     commitOnAutoCommit(writeMetadata);
     if (!writeMetadata.getCommitMetadata().isPresent()) {
       HoodieCommitMetadata commitMetadata = CommitUtils.buildMetadata(writeMetadata.getWriteStats().get(), writeMetadata.getPartitionToReplaceFileIds(),

hudi-client/hudi-spark-client/src/main/java/org/apache/hudi/client/SparkRDDWriteClient.java

@@ -18,6 +18,8 @@
 
 package org.apache.hudi.client;
 
+import org.apache.hudi.avro.model.HoodieClusteringGroup;
+import org.apache.hudi.avro.model.HoodieClusteringPlan;
 import org.apache.hudi.client.common.HoodieSparkEngineContext;
 import org.apache.hudi.client.embedded.EmbeddedTimelineService;
 import org.apache.hudi.client.utils.TransactionUtils;
@@ -37,7 +39,9 @@
 import org.apache.hudi.common.table.timeline.HoodieActiveTimeline;
 import org.apache.hudi.common.table.timeline.HoodieInstant;
 import org.apache.hudi.common.table.timeline.HoodieTimeline;
+import org.apache.hudi.common.util.ClusteringUtils;
 import org.apache.hudi.common.util.Option;
+import org.apache.hudi.common.util.collection.Pair;
 import org.apache.hudi.config.HoodieWriteConfig;
 import org.apache.hudi.data.HoodieJavaRDD;
 import org.apache.hudi.exception.HoodieClusteringException;
@@ -356,6 +360,16 @@ public HoodieWriteMetadata<JavaRDD<WriteStatus>> cluster(String clusteringInstan
     LOG.info("Starting clustering at " + clusteringInstant);
     HoodieWriteMetadata<HoodieData<WriteStatus>> writeMetadata = table.cluster(context, clusteringInstant);
     HoodieWriteMetadata<JavaRDD<WriteStatus>> clusteringMetadata = writeMetadata.clone(HoodieJavaRDD.getJavaRDD(writeMetadata.getWriteStatuses()));
+    if (clusteringMetadata.getWriteStatuses().isEmpty()) {
+      HoodieClusteringPlan clusteringPlan = ClusteringUtils.getClusteringPlan(
+              table.getMetaClient(), HoodieTimeline.getReplaceCommitRequestedInstant(clusteringInstant))
+          .map(Pair::getRight).orElseThrow(() -> new HoodieClusteringException(
+              "Unable to read clustering plan for instant: " + clusteringInstant));
+      throw new HoodieClusteringException("Clustering plan produced 0 WriteStatus for " + clusteringInstant
+          + " #groups: " + clusteringPlan.getInputGroups().size() + " expected at least "
+          + clusteringPlan.getInputGroups().stream().mapToInt(HoodieClusteringGroup::getNumOutputFileGroups).sum()
+          + " write statuses");
+    }
     // TODO : Where is shouldComplete used ?
     if (shouldComplete && clusteringMetadata.getCommitMetadata().isPresent()) {
       completeTableService(TableServiceType.CLUSTER, clusteringMetadata.getCommitMetadata().get(), table, clusteringInstant);

hudi-client/hudi-spark-client/src/test/java/org/apache/hudi/client/functional/TestHoodieClientOnCopyOnWriteStorage.java

@@ -45,6 +45,7 @@
 import org.apache.hudi.common.model.HoodieKey;
 import org.apache.hudi.common.model.HoodieRecord;
 import org.apache.hudi.common.model.HoodieRecordPayload;
+import org.apache.hudi.common.model.HoodieReplaceCommitMetadata;
 import org.apache.hudi.common.model.HoodieWriteStat;
 import org.apache.hudi.common.model.IOType;
 import org.apache.hudi.common.model.WriteOperationType;
@@ -106,6 +107,7 @@
 
 import org.apache.avro.generic.GenericRecord;
 import org.apache.hadoop.fs.FSDataInputStream;
+import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.Path;
 import org.apache.log4j.LogManager;
 import org.apache.log4j.Logger;
@@ -1456,6 +1458,41 @@ public void testSimpleClustering(boolean populateMetaFields, boolean preserveCom
     testInsertAndClustering(clusteringConfig, populateMetaFields, true, false, SqlQueryEqualityPreCommitValidator.class.getName(), COUNT_SQL_QUERY_FOR_VALIDATION, "");
   }
 
+  @Test
+  public void testAndValidateClusteringOutputFiles() throws IOException {
+    String partitionPath = "2015/03/16";
+    testInsertTwoBatches(true, partitionPath);
+
+    // Trigger clustering
+    HoodieWriteConfig.Builder cfgBuilder = getConfigBuilder().withEmbeddedTimelineServerEnabled(false).withAutoCommit(false)
+        .withClusteringConfig(HoodieClusteringConfig.newBuilder().withInlineClustering(true).withInlineClusteringNumCommits(2).build());
+    try (SparkRDDWriteClient client = getHoodieWriteClient(cfgBuilder.build())) {
+      int numRecords = 200;
+      String newCommitTime = HoodieActiveTimeline.createNewInstantTime();
+      List<HoodieRecord> records1 = dataGen.generateInserts(newCommitTime, numRecords);
+      client.startCommitWithTime(newCommitTime);
+      JavaRDD<HoodieRecord> insertRecordsRDD1 = jsc.parallelize(records1, 2);
+      JavaRDD<WriteStatus> statuses = client.insert(insertRecordsRDD1, newCommitTime);
+      client.commit(newCommitTime, statuses);
+      List<WriteStatus> statusList = statuses.collect();
+      assertNoWriteErrors(statusList);
+
+      metaClient = HoodieTableMetaClient.reload(metaClient);
+      HoodieInstant replaceCommitInstant = metaClient.getActiveTimeline().getCompletedReplaceTimeline().firstInstant().get();
+      HoodieReplaceCommitMetadata replaceCommitMetadata = HoodieReplaceCommitMetadata
+          .fromBytes(metaClient.getActiveTimeline().getInstantDetails(replaceCommitInstant).get(), HoodieReplaceCommitMetadata.class);
+
+      List<String> filesFromReplaceCommit = new ArrayList<>();
+      replaceCommitMetadata.getPartitionToWriteStats().forEach((k,v) -> v.forEach(entry -> filesFromReplaceCommit.add(entry.getPath())));
+
+      // find all parquet files created as part of clustering. Verify it matces w/ whats found in replace commit metadata.
+      FileStatus[] fileStatuses = fs.listStatus(new Path(basePath + "/" + partitionPath));
+      List<String> clusteredFiles = Arrays.stream(fileStatuses).filter(entry -> entry.getPath().getName().contains(replaceCommitInstant.getTimestamp()))
+          .map(fileStatus -> partitionPath + "/" + fileStatus.getPath().getName()).collect(Collectors.toList());
+      assertEquals(clusteredFiles, filesFromReplaceCommit);
+    }
+  }
+
   @Test
   public void testRolblackOfRegularCommitWithPendingReplaceCommitInTimeline() throws Exception {
     HoodieClusteringConfig clusteringConfig = HoodieClusteringConfig.newBuilder().withClusteringMaxNumGroups(10)
@@ -1707,18 +1744,22 @@ private List<HoodieRecord> testInsertAndClustering(HoodieClusteringConfig cluste
     return allRecords.getLeft().getLeft();
   }
 
+  private Pair<Pair<List<HoodieRecord>, List<String>>, Set<HoodieFileGroupId>> testInsertTwoBatches(boolean populateMetaFields) throws IOException {
+    return testInsertTwoBatches(populateMetaFields, "2015/03/16");
+  }
+
   /**
    * This method returns following three items:
    * 1. List of all HoodieRecord written in the two batches of insert.
    * 2. Commit instants of the two batches.
    * 3. List of new file group ids that were written in the two batches.
    */
-  private Pair<Pair<List<HoodieRecord>, List<String>>, Set<HoodieFileGroupId>> testInsertTwoBatches(boolean populateMetaFields) throws IOException {
+  private Pair<Pair<List<HoodieRecord>, List<String>>, Set<HoodieFileGroupId>> testInsertTwoBatches(boolean populateMetaFields, String partitionPath) throws IOException {
     // create config to not update small files.
     HoodieWriteConfig config = getSmallInsertWriteConfig(2000, TRIP_EXAMPLE_SCHEMA, 10, false, populateMetaFields,
         populateMetaFields ? new Properties() : getPropertiesForKeyGen());
     SparkRDDWriteClient client = getHoodieWriteClient(config);
-    dataGen = new HoodieTestDataGenerator(new String[] {"2015/03/16"});
+    dataGen = new HoodieTestDataGenerator(new String[] {partitionPath});
     String commitTime1 = HoodieActiveTimeline.createNewInstantTime();
     List<HoodieRecord> records1 = dataGen.generateInserts(commitTime1, 200);
     List<WriteStatus> statuses1 = writeAndVerifyBatch(client, records1, commitTime1, populateMetaFields);