danielxjd commented on a change in pull request #12223:
URL: https://github.com/apache/beam/pull/12223#discussion_r467159080



##########
File path: 
sdks/java/io/parquet/src/main/java/org/apache/beam/sdk/io/parquet/ParquetIO.java
##########
@@ -230,14 +281,284 @@ public ReadFiles withAvroDataModel(GenericData model) {
       return toBuilder().setAvroDataModel(model).build();
     }
 
+    public ReadFiles withSplit() {
+      return toBuilder().setSplit(true).build();
+    }
+
     @Override
     public PCollection<GenericRecord> expand(PCollection<FileIO.ReadableFile> 
input) {
       checkNotNull(getSchema(), "Schema can not be null");
+      if (getSplit()) {
+        return input
+            .apply(ParDo.of(new SplitReadFn(getAvroDataModel())))
+            .setCoder(AvroCoder.of(getSchema()));
+      }
       return input
           .apply(ParDo.of(new ReadFn(getAvroDataModel())))
           .setCoder(AvroCoder.of(getSchema()));
     }
 
+    @DoFn.BoundedPerElement
+    static class SplitReadFn extends DoFn<FileIO.ReadableFile, GenericRecord> {
+      private Class<? extends GenericData> modelClass;
+      private static final Logger LOG = 
LoggerFactory.getLogger(SplitReadFn.class);
+      private static final long SPLIT_LIMIT = 64000000;
+      ReadSupport<GenericRecord> readSupport;
+
+      SplitReadFn(GenericData model) {
+        this.modelClass = model != null ? model.getClass() : null;
+      }
+
+      private static <K, V> Map<K, Set<V>> toSetMultiMap(Map<K, V> map) {
+        Map<K, Set<V>> setMultiMap = new HashMap<K, Set<V>>();
+        for (Map.Entry<K, V> entry : map.entrySet()) {
+          Set<V> set = new HashSet<V>();
+          set.add(entry.getValue());
+          setMultiMap.put(entry.getKey(), Collections.unmodifiableSet(set));
+        }
+        return Collections.unmodifiableMap(setMultiMap);
+      }
+
+      public InputFile getInputFile(FileIO.ReadableFile file) throws 
IOException {
+        if (!file.getMetadata().isReadSeekEfficient()) {
+          throw new RuntimeException(
+              String.format("File has to be seekable: %s", 
file.getMetadata().resourceId()));
+        }
+        return new BeamParquetInputFile(file.openSeekable());
+      }
+
+      @ProcessElement
+      public void processElement(
+          @Element FileIO.ReadableFile file,
+          RestrictionTracker<OffsetRange, Long> tracker,
+          OutputReceiver<GenericRecord> outputReceiver)
+          throws Exception {
+        ReadSupport<GenericRecord> readSupport;
+        InputFile inputFile = getInputFile(file);
+        Configuration conf = setConf();
+        GenericData model = null;
+        if (modelClass != null) {
+          model = (GenericData) modelClass.getMethod("get").invoke(null);
+        }
+        readSupport = new AvroReadSupport<GenericRecord>(model);
+        ParquetReadOptions options = HadoopReadOptions.builder(conf).build();
+        ParquetFileReader reader = ParquetFileReader.open(inputFile, options);
+        Filter filter = checkNotNull(options.getRecordFilter(), "filter");
+        conf = ((HadoopReadOptions) options).getConf();
+        FileMetaData parquetFileMetadata = 
reader.getFooter().getFileMetaData();
+        MessageType fileSchema = parquetFileMetadata.getSchema();
+        Map<String, String> fileMetadata = 
parquetFileMetadata.getKeyValueMetaData();
+
+        ReadSupport.ReadContext readContext =
+            readSupport.init(new InitContext(conf, 
toSetMultiMap(fileMetadata), fileSchema));
+        ColumnIOFactory columnIOFactory = new 
ColumnIOFactory(parquetFileMetadata.getCreatedBy());
+        MessageType requestedSchema = readContext.getRequestedSchema();
+        RecordMaterializer<GenericRecord> recordConverter =
+            readSupport.prepareForRead(conf, fileMetadata, fileSchema, 
readContext);
+        boolean strictTypeChecking = options.isEnabled(STRICT_TYPE_CHECKING, 
true);
+        boolean filterRecords = options.useRecordFilter();
+        reader.setRequestedSchema(requestedSchema);
+        MessageColumnIO columnIO =
+            columnIOFactory.getColumnIO(requestedSchema, fileSchema, 
strictTypeChecking);
+        long currentBlock = tracker.currentRestriction().getFrom();
+        for (int i = 0; i < currentBlock; i++) {
+          reader.skipNextRowGroup();
+        }
+
+        while ((tracker).tryClaim(currentBlock)) {
+          LOG.info("reading block" + currentBlock);
+          PageReadStore pages = reader.readNextRowGroup();
+          currentBlock += 1;
+          RecordReader<GenericRecord> recordReader =
+              columnIO.getRecordReader(
+                  pages, recordConverter, filterRecords ? filter : 
FilterCompat.NOOP);
+          long currentRow = 0;
+          long totalRows = pages.getRowCount();
+          while (currentRow < totalRows) {
+            try {
+              GenericRecord record;
+              currentRow += 1;
+              try {
+                record = recordReader.read();
+              } catch (RecordMaterializer.RecordMaterializationException e) {
+                LOG.debug("skipping a corrupt record");
+                continue;
+              }
+              if (record == null) {
+                // only happens with FilteredRecordReader at end of block
+                LOG.debug("filtered record reader reached end of block");
+                break;
+              }
+              if (tracker instanceof BlockTracker) {
+                ((BlockTracker) tracker).makeProgress();
+              }
+              if (recordReader.shouldSkipCurrentRecord()) {
+                // this record is being filtered via the filter2 package
+                LOG.debug("skipping record");
+                continue;
+              }
+              outputReceiver.output(record);
+            } catch (RuntimeException e) {
+
+              throw new ParquetDecodingException(
+                  format(
+                      "Can not read value at %d in block %d in file %s",
+                      currentRow, currentBlock, file.toString()),
+                  e);
+            }
+          }
+          LOG.info("finish read " + currentRow + " rows");
+        }
+      }
+
+      public Configuration setConf() throws Exception {
+        Configuration conf = new Configuration();
+        GenericData model = null;
+        if (modelClass != null) {
+          model = (GenericData) modelClass.getMethod("get").invoke(null);
+        }
+        if (model != null
+            && (model.getClass() == GenericData.class || model.getClass() == 
SpecificData.class)) {
+          conf.setBoolean(AvroReadSupport.AVRO_COMPATIBILITY, true);
+        } else {
+          conf.setBoolean(AvroReadSupport.AVRO_COMPATIBILITY, false);
+        }
+        return conf;
+      }
+
+      @GetInitialRestriction
+      public OffsetRange getInitialRestriction(@Element FileIO.ReadableFile 
file) throws Exception {
+        InputFile inputFile = getInputFile(file);
+        Configuration conf = setConf();
+        ParquetReadOptions options = HadoopReadOptions.builder(conf).build();
+        ParquetFileReader reader = ParquetFileReader.open(inputFile, options);
+        return new OffsetRange(0, reader.getRowGroups().size());
+      }
+
+      @SplitRestriction
+      public void split(
+          @Restriction OffsetRange restriction,
+          OutputReceiver<OffsetRange> out,
+          @Element FileIO.ReadableFile file)
+          throws Exception {
+        InputFile inputFile = getInputFile(file);
+        Configuration conf = setConf();
+        ParquetReadOptions options = HadoopReadOptions.builder(conf).build();
+        ParquetFileReader reader = ParquetFileReader.open(inputFile, options);
+        List<BlockMetaData> rowGroups = reader.getRowGroups();
+        for (OffsetRange offsetRange :
+            splitBlockWithLimit(
+                restriction.getFrom(), restriction.getTo(), rowGroups, 
SPLIT_LIMIT / 3)) {
+          out.output(offsetRange);
+        }
+      }
+
+      public ArrayList<OffsetRange> splitBlockWithLimit(
+          long start, long end, List<BlockMetaData> blockList, long limit) {
+        ArrayList<OffsetRange> offsetList = new ArrayList<OffsetRange>();
+        long totalSize = 0;
+        long rangeStart = start;
+        long rangeEnd = start;
+        for (long i = start; i < end; i++) {
+          totalSize += blockList.get((int) i).getTotalByteSize();
+          rangeEnd += 1;

Review comment:
       they should have the same value.




----------------------------------------------------------------
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:
us...@infra.apache.org


Reply via email to