Rename VectorSerializer to IterativeVectorSerializer to distinguish i…

…t from BatchVectorSerializer

Summary:
To make the differences between VectorSerializer and BatchVectorSerializer more explicit, I'm renaming VectorSerializer to 
IterativeVectorSerializer.

I also rename createSerializer to createIterativeSerializer, however, since Presto uses createSerializer, I've left it in.  Once this 
diff lands, I'll land a change in Presto to use createIterativeSerializer, and then land a change back in Velox to remove 
createSerializer.

Reviewed By: bikramSingh91

Differential Revision: D53201916

velox/serializers/CompactRowSerializer.cpp

@@ -28,7 +28,7 @@ void CompactRowVectorSerde::estimateSerializedSize(
 }
 
 namespace {
-class CompactRowVectorSerializer : public VectorSerializer {
+class CompactRowVectorSerializer : public IterativeVectorSerializer {
  public:
   using TRowSize = uint32_t;
 
@@ -120,7 +120,8 @@ std::string concatenatePartialRow(
 
 } // namespace
 
-std::unique_ptr<VectorSerializer> CompactRowVectorSerde::createSerializer(
+std::unique_ptr<IterativeVectorSerializer>
+CompactRowVectorSerde::createIterativeSerializer(
     RowTypePtr /* type */,
     int32_t /* numRows */,
     StreamArena* streamArena,

velox/serializers/CompactRowSerializer.h

@@ -33,7 +33,7 @@ class CompactRowVectorSerde : public VectorSerde {
 
   // This method is not used in production code. It is only used to
   // support round-trip tests for deserialization.
-  std::unique_ptr<VectorSerializer> createSerializer(
+  std::unique_ptr<IterativeVectorSerializer> createIterativeSerializer(
       RowTypePtr type,
       int32_t numRows,
       StreamArena* streamArena,

velox/serializers/PrestoSerializer.cpp

@@ -3316,9 +3316,9 @@ class PrestoBatchVectorSerializer : public BatchVectorSerializer {
   const std::unique_ptr<folly::io::Codec> codec_;
 };
 
-class PrestoVectorSerializer : public VectorSerializer {
+class PrestoIterativeVectorSerializer : public IterativeVectorSerializer {
  public:
-  PrestoVectorSerializer(
+  PrestoIterativeVectorSerializer(
       const RowTypePtr& rowType,
       std::vector<VectorEncoding::Simple> encodings,
       int32_t numRows,
@@ -3349,7 +3349,7 @@ class PrestoVectorSerializer : public VectorSerializer {
   // Constructor that takes a row vector instead of only the types. This is
   // different because then we know exactly how each vector is encoded
   // (recursively).
-  PrestoVectorSerializer(
+  PrestoIterativeVectorSerializer(
       const RowVectorPtr& rowVector,
       StreamArena* streamArena,
       bool useLosslessTimestamp,
@@ -3455,13 +3455,14 @@ void PrestoVectorSerde::estimateSerializedSize(
   estimateSerializedSizeInt(vector->loadedVector(), rows, sizes, scratch);
 }
 
-std::unique_ptr<VectorSerializer> PrestoVectorSerde::createSerializer(
+std::unique_ptr<IterativeVectorSerializer>
+PrestoVectorSerde::createIterativeSerializer(
     RowTypePtr type,
     int32_t numRows,
     StreamArena* streamArena,
     const Options* options) {
   const auto prestoOptions = toPrestoOptions(options);
-  return std::make_unique<PrestoVectorSerializer>(
+  return std::make_unique<PrestoIterativeVectorSerializer>(
       type,
       prestoOptions.encodings,
       numRows,
@@ -3484,7 +3485,7 @@ void PrestoVectorSerde::deprecatedSerializeEncoded(
     const Options* options,
     OutputStream* out) {
   auto prestoOptions = toPrestoOptions(options);
-  auto serializer = std::make_unique<PrestoVectorSerializer>(
+  auto serializer = std::make_unique<PrestoIterativeVectorSerializer>(
       vector,
       streamArena,
       prestoOptions.useLosslessTimestamp,

velox/serializers/PrestoSerializer.h

@@ -24,10 +24,11 @@ namespace facebook::velox::serializer::presto {
 /// There are two ways to serialize data using PrestoVectorSerde:
 ///
 /// 1. In order to append multiple RowVectors into the same serialized payload,
-/// one can first create a VectorSerializer using createSerializer(), then
-/// append successive RowVectors using VectorSerializer::append(). In this case,
-/// since different RowVector might encode columns differently, data is always
-/// flattened in the serialized payload.
+/// one can first create an IterativeVectorSerializer using
+/// createIterativeSerializer(), then append successive RowVectors using
+/// IterativeVectorSerializer::append(). In this case, since different RowVector
+/// might encode columns differently, data is always flattened in the serialized
+/// payload.
 ///
 /// Note that there are two flavors of append(), one that takes a range of rows,
 /// and one that takes a list of row ids. The former is useful when serializing
@@ -76,7 +77,7 @@ class PrestoVectorSerde : public VectorSerde {
       vector_size_t** sizes,
       Scratch& scratch) override;
 
-  std::unique_ptr<VectorSerializer> createSerializer(
+  std::unique_ptr<IterativeVectorSerializer> createIterativeSerializer(
       RowTypePtr type,
       int32_t numRows,
       StreamArena* streamArena,

velox/serializers/UnsafeRowSerializer.cpp

@@ -29,7 +29,7 @@ void UnsafeRowVectorSerde::estimateSerializedSize(
 }
 
 namespace {
-class UnsafeRowVectorSerializer : public VectorSerializer {
+class UnsafeRowVectorSerializer : public IterativeVectorSerializer {
  public:
   using TRowSize = uint32_t;
 
@@ -122,7 +122,8 @@ std::string concatenatePartialRow(
 
 } // namespace
 
-std::unique_ptr<VectorSerializer> UnsafeRowVectorSerde::createSerializer(
+std::unique_ptr<IterativeVectorSerializer>
+UnsafeRowVectorSerde::createIterativeSerializer(
     RowTypePtr /* type */,
     int32_t /* numRows */,
     StreamArena* streamArena,

velox/serializers/UnsafeRowSerializer.h

@@ -31,7 +31,7 @@ class UnsafeRowVectorSerde : public VectorSerde {
 
   // This method is not used in production code. It is only used to
   // support round-trip tests for deserialization.
-  std::unique_ptr<VectorSerializer> createSerializer(
+  std::unique_ptr<IterativeVectorSerializer> createIterativeSerializer(
       RowTypePtr type,
       int32_t numRows,
       StreamArena* streamArena,

velox/serializers/tests/CompactRowSerializerTest.cpp

@@ -43,7 +43,8 @@ class CompactRowSerializerTest : public ::testing::Test,
 
     auto arena = std::make_unique<StreamArena>(pool_.get());
     auto rowType = asRowType(rowVector->type());
-    auto serializer = serde_->createSerializer(rowType, numRows, arena.get());
+    auto serializer =
+        serde_->createIterativeSerializer(rowType, numRows, arena.get());
 
     Scratch scratch;
     serializer->append(rowVector, folly::Range(rows.data(), numRows), scratch);

velox/serializers/tests/PrestoSerializerTest.cpp

@@ -92,8 +92,8 @@ class PrestoSerializerTest
     auto rowType = asRowType(rowVector->type());
     auto numRows = rowVector->size();
     auto paramOptions = getParamSerdeOptions(serdeOptions);
-    auto serializer =
-        serde_->createSerializer(rowType, numRows, arena.get(), &paramOptions);
+    auto serializer = serde_->createIterativeSerializer(
+        rowType, numRows, arena.get(), &paramOptions);
     vector_size_t sizeEstimate = 0;
 
     Scratch scratch;

velox/serializers/tests/UnsafeRowSerializerTest.cpp

@@ -43,7 +43,8 @@ class UnsafeRowSerializerTest : public ::testing::Test,
 
     auto arena = std::make_unique<StreamArena>(pool_.get());
     auto rowType = std::dynamic_pointer_cast<const RowType>(rowVector->type());
-    auto serializer = serde_->createSerializer(rowType, numRows, arena.get());
+    auto serializer =
+        serde_->createIterativeSerializer(rowType, numRows, arena.get());
 
     Scratch scratch;
     serializer->append(rowVector, folly::Range(rows.data(), numRows), scratch);

velox/vector/VectorStream.cpp

@@ -41,7 +41,7 @@ class DefaultBatchVectorSerializer : public BatchVectorSerializer {
     }
 
     StreamArena arena(pool_);
-    auto serializer = serde_->createSerializer(
+    auto serializer = serde_->createIterativeSerializer(
         asRowType(vector->type()), numRows, &arena, options_);
     serializer->append(vector, ranges, scratch);
     serializer->flush(stream);
@@ -67,7 +67,7 @@ getNamedVectorSerdeImpl() {
 
 } // namespace
 
-void VectorSerializer::append(const RowVectorPtr& vector) {
+void IterativeVectorSerializer::append(const RowVectorPtr& vector) {
   const IndexRange allRows{0, vector->size()};
   Scratch scratch;
   append(vector, folly::Range(&allRows, 1), scratch);
@@ -144,7 +144,7 @@ void VectorStreamGroup::createStreamTree(
     RowTypePtr type,
     int32_t numRows,
     const VectorSerde::Options* options) {
-  serializer_ = serde_->createSerializer(type, numRows, this, options);
+  serializer_ = serde_->createIterativeSerializer(type, numRows, this, options);
 }
 
 void VectorStreamGroup::append(

velox/vector/VectorStream.h

@@ -39,9 +39,9 @@ struct IndexRange {
 /// Uses successive calls to `append` to add more rows to the serialization
 /// buffer.  Then call `flush` to write the aggregate serialized data to an
 /// OutputStream.
-class VectorSerializer {
+class IterativeVectorSerializer {
  public:
-  virtual ~VectorSerializer() = default;
+  virtual ~IterativeVectorSerializer() = default;
 
   /// Serialize a subset of rows in a vector.
   virtual void append(
@@ -159,7 +159,19 @@ class VectorSerde {
   ///
   /// This is more appropriate if the use case involves many small writes, e.g.
   /// partitioning a RowVector across multiple destinations.
-  virtual std::unique_ptr<VectorSerializer> createSerializer(
+  ///
+  /// TODO: Remove createSerializer once Presto is updated to call
+  /// createIterativeSerializer.
+  virtual std::unique_ptr<IterativeVectorSerializer> createSerializer(
+      RowTypePtr type,
+      int32_t numRows,
+      StreamArena* streamArena,
+      const Options* options = nullptr) {
+    return createIterativeSerializer(
+        std::move(type), numRows, streamArena, options);
+  }
+
+  virtual std::unique_ptr<IterativeVectorSerializer> createIterativeSerializer(
       RowTypePtr type,
       int32_t numRows,
       StreamArena* streamArena,
@@ -298,7 +310,7 @@ class VectorStreamGroup : public StreamArena {
       const VectorSerde::Options* options = nullptr);
 
  private:
-  std::unique_ptr<VectorSerializer> serializer_;
+  std::unique_ptr<IterativeVectorSerializer> serializer_;
   VectorSerde* serde_{nullptr};
 };
 

velox/vector/tests/VectorStreamTest.cpp

@@ -25,7 +25,7 @@ class MockVectorSerde : public VectorSerde {
       const folly::Range<const IndexRange*>& ranges,
       vector_size_t** sizes) override {}
 
-  std::unique_ptr<VectorSerializer> createSerializer(
+  std::unique_ptr<IterativeVectorSerializer> createIterativeSerializer(
       RowTypePtr type,
       int32_t numRows,
       StreamArena* streamArena,