/
mod.rs
1103 lines (957 loc) · 38.2 KB
/
mod.rs
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// 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.
//! Contains all supported encoders for Parquet.
use std::{cmp, marker::PhantomData};
use crate::basic::*;
use crate::data_type::private::ParquetValueType;
use crate::data_type::*;
use crate::encodings::rle::RleEncoder;
use crate::errors::{ParquetError, Result};
use crate::schema::types::ColumnDescPtr;
use crate::util::{
bit_util::{self, num_required_bits, BitWriter},
memory::ByteBufferPtr,
};
pub use dict_encoder::DictEncoder;
mod dict_encoder;
// ----------------------------------------------------------------------
// Encoders
/// An Parquet encoder for the data type `T`.
///
/// Currently this allocates internal buffers for the encoded values. After done putting
/// values, caller should call `flush_buffer()` to get an immutable buffer pointer.
pub trait Encoder<T: DataType> {
/// Encodes data from `values`.
fn put(&mut self, values: &[T::T]) -> Result<()>;
/// Encodes data from `values`, which contains spaces for null values, that is
/// identified by `valid_bits`.
///
/// Returns the number of non-null values encoded.
fn put_spaced(&mut self, values: &[T::T], valid_bits: &[u8]) -> Result<usize> {
let num_values = values.len();
let mut buffer = Vec::with_capacity(num_values);
// TODO: this is pretty inefficient. Revisit in future.
for (i, item) in values.iter().enumerate().take(num_values) {
if bit_util::get_bit(valid_bits, i) {
buffer.push(item.clone());
}
}
self.put(&buffer[..])?;
Ok(buffer.len())
}
/// Returns the encoding type of this encoder.
fn encoding(&self) -> Encoding;
/// Returns an estimate of the encoded data, in bytes.
/// Method call must be O(1).
fn estimated_data_encoded_size(&self) -> usize;
/// Flushes the underlying byte buffer that's being processed by this encoder, and
/// return the immutable copy of it. This will also reset the internal state.
fn flush_buffer(&mut self) -> Result<ByteBufferPtr>;
}
/// Gets a encoder for the particular data type `T` and encoding `encoding`. Memory usage
/// for the encoder instance is tracked by `mem_tracker`.
pub fn get_encoder<T: DataType>(
desc: ColumnDescPtr,
encoding: Encoding,
) -> Result<Box<dyn Encoder<T>>> {
let encoder: Box<dyn Encoder<T>> = match encoding {
Encoding::PLAIN => Box::new(PlainEncoder::new(desc, vec![])),
Encoding::RLE_DICTIONARY | Encoding::PLAIN_DICTIONARY => {
return Err(general_err!(
"Cannot initialize this encoding through this function"
));
}
Encoding::RLE => Box::new(RleValueEncoder::new()),
Encoding::DELTA_BINARY_PACKED => Box::new(DeltaBitPackEncoder::new()),
Encoding::DELTA_LENGTH_BYTE_ARRAY => Box::new(DeltaLengthByteArrayEncoder::new()),
Encoding::DELTA_BYTE_ARRAY => Box::new(DeltaByteArrayEncoder::new()),
e => return Err(nyi_err!("Encoding {} is not supported", e)),
};
Ok(encoder)
}
// ----------------------------------------------------------------------
// Plain encoding
/// Plain encoding that supports all types.
/// Values are encoded back to back.
/// The plain encoding is used whenever a more efficient encoding can not be used.
/// It stores the data in the following format:
/// - BOOLEAN - 1 bit per value, 0 is false; 1 is true.
/// - INT32 - 4 bytes per value, stored as little-endian.
/// - INT64 - 8 bytes per value, stored as little-endian.
/// - FLOAT - 4 bytes per value, stored as IEEE little-endian.
/// - DOUBLE - 8 bytes per value, stored as IEEE little-endian.
/// - BYTE_ARRAY - 4 byte length stored as little endian, followed by bytes.
/// - FIXED_LEN_BYTE_ARRAY - just the bytes are stored.
pub struct PlainEncoder<T: DataType> {
buffer: Vec<u8>,
bit_writer: BitWriter,
desc: ColumnDescPtr,
_phantom: PhantomData<T>,
}
impl<T: DataType> PlainEncoder<T> {
/// Creates new plain encoder.
pub fn new(desc: ColumnDescPtr, buffer: Vec<u8>) -> Self {
Self {
buffer,
bit_writer: BitWriter::new(256),
desc,
_phantom: PhantomData,
}
}
}
impl<T: DataType> Encoder<T> for PlainEncoder<T> {
// Performance Note:
// As far as can be seen these functions are rarely called and as such we can hint to the
// compiler that they dont need to be folded into hot locations in the final output.
#[cold]
fn encoding(&self) -> Encoding {
Encoding::PLAIN
}
fn estimated_data_encoded_size(&self) -> usize {
self.buffer.len() + self.bit_writer.bytes_written()
}
#[inline]
fn flush_buffer(&mut self) -> Result<ByteBufferPtr> {
self.buffer
.extend_from_slice(self.bit_writer.flush_buffer());
self.bit_writer.clear();
Ok(std::mem::take(&mut self.buffer).into())
}
#[inline]
fn put(&mut self, values: &[T::T]) -> Result<()> {
T::T::encode(values, &mut self.buffer, &mut self.bit_writer)?;
Ok(())
}
}
// ----------------------------------------------------------------------
// RLE encoding
const DEFAULT_RLE_BUFFER_LEN: usize = 1024;
/// RLE/Bit-Packing hybrid encoding for values.
/// Currently is used only for data pages v2 and supports boolean types.
pub struct RleValueEncoder<T: DataType> {
// Buffer with raw values that we collect,
// when flushing buffer they are encoded using RLE encoder
encoder: Option<RleEncoder>,
_phantom: PhantomData<T>,
}
impl<T: DataType> RleValueEncoder<T> {
/// Creates new rle value encoder.
pub fn new() -> Self {
Self {
encoder: None,
_phantom: PhantomData,
}
}
}
impl<T: DataType> Encoder<T> for RleValueEncoder<T> {
#[inline]
fn put(&mut self, values: &[T::T]) -> Result<()> {
ensure_phys_ty!(Type::BOOLEAN, "RleValueEncoder only supports BoolType");
let rle_encoder = self.encoder.get_or_insert_with(|| {
let mut buffer = Vec::with_capacity(DEFAULT_RLE_BUFFER_LEN);
// Reserve space for length
buffer.extend_from_slice(&[0; 4]);
RleEncoder::new_from_buf(1, buffer)
});
for value in values {
let value = value.as_u64()?;
rle_encoder.put(value)
}
Ok(())
}
// Performance Note:
// As far as can be seen these functions are rarely called and as such we can hint to the
// compiler that they dont need to be folded into hot locations in the final output.
#[cold]
fn encoding(&self) -> Encoding {
Encoding::RLE
}
#[inline]
fn estimated_data_encoded_size(&self) -> usize {
match self.encoder {
Some(ref enc) => enc.len(),
None => 0,
}
}
#[inline]
fn flush_buffer(&mut self) -> Result<ByteBufferPtr> {
ensure_phys_ty!(Type::BOOLEAN, "RleValueEncoder only supports BoolType");
let rle_encoder = self
.encoder
.take()
.expect("RLE value encoder is not initialized");
// Flush all encoder buffers and raw values
let mut buf = rle_encoder.consume();
assert!(buf.len() > 4, "should have had padding inserted");
// Note that buf does not have any offset, all data is encoded bytes
let len = (buf.len() - 4) as i32;
buf[..4].copy_from_slice(&len.to_le_bytes());
Ok(ByteBufferPtr::new(buf))
}
}
// ----------------------------------------------------------------------
// DELTA_BINARY_PACKED encoding
const MAX_PAGE_HEADER_WRITER_SIZE: usize = 32;
const MAX_BIT_WRITER_SIZE: usize = 10 * 1024 * 1024;
const DEFAULT_BLOCK_SIZE: usize = 128;
const DEFAULT_NUM_MINI_BLOCKS: usize = 4;
/// Delta bit packed encoder.
/// Consists of a header followed by blocks of delta encoded values binary packed.
///
/// Delta-binary-packing:
/// ```shell
/// [page-header] [block 1], [block 2], ... [block N]
/// ```
///
/// Each page header consists of:
/// ```shell
/// [block size] [number of miniblocks in a block] [total value count] [first value]
/// ```
///
/// Each block consists of:
/// ```shell
/// [min delta] [list of bitwidths of miniblocks] [miniblocks]
/// ```
///
/// Current implementation writes values in `put` method, multiple calls to `put` to
/// existing block or start new block if block size is exceeded. Calling `flush_buffer`
/// writes out all data and resets internal state, including page header.
///
/// Supports only INT32 and INT64.
pub struct DeltaBitPackEncoder<T: DataType> {
page_header_writer: BitWriter,
bit_writer: BitWriter,
total_values: usize,
first_value: i64,
current_value: i64,
block_size: usize,
mini_block_size: usize,
num_mini_blocks: usize,
values_in_block: usize,
deltas: Vec<i64>,
_phantom: PhantomData<T>,
}
impl<T: DataType> DeltaBitPackEncoder<T> {
/// Creates new delta bit packed encoder.
pub fn new() -> Self {
let block_size = DEFAULT_BLOCK_SIZE;
let num_mini_blocks = DEFAULT_NUM_MINI_BLOCKS;
let mini_block_size = block_size / num_mini_blocks;
assert_eq!(mini_block_size % 8, 0);
Self::assert_supported_type();
DeltaBitPackEncoder {
page_header_writer: BitWriter::new(MAX_PAGE_HEADER_WRITER_SIZE),
bit_writer: BitWriter::new(MAX_BIT_WRITER_SIZE),
total_values: 0,
first_value: 0,
current_value: 0, // current value to keep adding deltas
block_size, // can write fewer values than block size for last block
mini_block_size,
num_mini_blocks,
values_in_block: 0, // will be at most block_size
deltas: vec![0; block_size],
_phantom: PhantomData,
}
}
/// Writes page header for blocks, this method is invoked when we are done encoding
/// values. It is also okay to encode when no values have been provided
fn write_page_header(&mut self) {
// We ignore the result of each 'put' operation, because
// MAX_PAGE_HEADER_WRITER_SIZE is chosen to fit all header values and
// guarantees that writes will not fail.
// Write the size of each block
self.page_header_writer.put_vlq_int(self.block_size as u64);
// Write the number of mini blocks
self.page_header_writer
.put_vlq_int(self.num_mini_blocks as u64);
// Write the number of all values (including non-encoded first value)
self.page_header_writer
.put_vlq_int(self.total_values as u64);
// Write first value
self.page_header_writer.put_zigzag_vlq_int(self.first_value);
}
// Write current delta buffer (<= 'block size' values) into bit writer
#[inline(never)]
fn flush_block_values(&mut self) -> Result<()> {
if self.values_in_block == 0 {
return Ok(());
}
let mut min_delta = i64::MAX;
for i in 0..self.values_in_block {
min_delta = cmp::min(min_delta, self.deltas[i]);
}
// Write min delta
self.bit_writer.put_zigzag_vlq_int(min_delta);
// Slice to store bit width for each mini block
let offset = self.bit_writer.skip(self.num_mini_blocks);
for i in 0..self.num_mini_blocks {
// Find how many values we need to encode - either block size or whatever
// values left
let n = cmp::min(self.mini_block_size, self.values_in_block);
if n == 0 {
// Decoders should be agnostic to the padding value, we therefore use 0xFF
// when running tests. However, not all implementations may handle this correctly
// so pad with 0 when not running tests
let pad_value = cfg!(test).then(|| 0xFF).unwrap_or(0);
for j in i..self.num_mini_blocks {
self.bit_writer.write_at(offset + j, pad_value);
}
break;
}
// Compute the max delta in current mini block
let mut max_delta = i64::MIN;
for j in 0..n {
max_delta =
cmp::max(max_delta, self.deltas[i * self.mini_block_size + j]);
}
// Compute bit width to store (max_delta - min_delta)
let bit_width =
num_required_bits(self.subtract_u64(max_delta, min_delta)) as usize;
self.bit_writer.write_at(offset + i, bit_width as u8);
// Encode values in current mini block using min_delta and bit_width
for j in 0..n {
let packed_value = self
.subtract_u64(self.deltas[i * self.mini_block_size + j], min_delta);
self.bit_writer.put_value(packed_value, bit_width);
}
// Pad the last block (n < mini_block_size)
for _ in n..self.mini_block_size {
self.bit_writer.put_value(0, bit_width);
}
self.values_in_block -= n;
}
assert_eq!(
self.values_in_block, 0,
"Expected 0 values in block, found {}",
self.values_in_block
);
Ok(())
}
}
// Implementation is shared between Int32Type and Int64Type,
// see `DeltaBitPackEncoderConversion` below for specifics.
impl<T: DataType> Encoder<T> for DeltaBitPackEncoder<T> {
fn put(&mut self, values: &[T::T]) -> Result<()> {
if values.is_empty() {
return Ok(());
}
// Define values to encode, initialize state
let mut idx = if self.total_values == 0 {
self.first_value = self.as_i64(values, 0);
self.current_value = self.first_value;
1
} else {
0
};
// Add all values (including first value)
self.total_values += values.len();
// Write block
while idx < values.len() {
let value = self.as_i64(values, idx);
self.deltas[self.values_in_block] = self.subtract(value, self.current_value);
self.current_value = value;
idx += 1;
self.values_in_block += 1;
if self.values_in_block == self.block_size {
self.flush_block_values()?;
}
}
Ok(())
}
// Performance Note:
// As far as can be seen these functions are rarely called and as such we can hint to the
// compiler that they dont need to be folded into hot locations in the final output.
#[cold]
fn encoding(&self) -> Encoding {
Encoding::DELTA_BINARY_PACKED
}
fn estimated_data_encoded_size(&self) -> usize {
self.bit_writer.bytes_written()
}
fn flush_buffer(&mut self) -> Result<ByteBufferPtr> {
// Write remaining values
self.flush_block_values()?;
// Write page header with total values
self.write_page_header();
let mut buffer = Vec::new();
buffer.extend_from_slice(self.page_header_writer.flush_buffer());
buffer.extend_from_slice(self.bit_writer.flush_buffer());
// Reset state
self.page_header_writer.clear();
self.bit_writer.clear();
self.total_values = 0;
self.first_value = 0;
self.current_value = 0;
self.values_in_block = 0;
Ok(buffer.into())
}
}
/// Helper trait to define specific conversions and subtractions when computing deltas
trait DeltaBitPackEncoderConversion<T: DataType> {
// Method should panic if type is not supported, otherwise no-op
fn assert_supported_type();
fn as_i64(&self, values: &[T::T], index: usize) -> i64;
fn subtract(&self, left: i64, right: i64) -> i64;
fn subtract_u64(&self, left: i64, right: i64) -> u64;
}
impl<T: DataType> DeltaBitPackEncoderConversion<T> for DeltaBitPackEncoder<T> {
#[inline]
fn assert_supported_type() {
ensure_phys_ty!(
Type::INT32 | Type::INT64,
"DeltaBitPackDecoder only supports Int32Type and Int64Type"
);
}
#[inline]
fn as_i64(&self, values: &[T::T], index: usize) -> i64 {
values[index]
.as_i64()
.expect("DeltaBitPackDecoder only supports Int32Type and Int64Type")
}
#[inline]
fn subtract(&self, left: i64, right: i64) -> i64 {
// It is okay for values to overflow, wrapping_sub wrapping around at the boundary
match T::get_physical_type() {
Type::INT32 => (left as i32).wrapping_sub(right as i32) as i64,
Type::INT64 => left.wrapping_sub(right),
_ => panic!("DeltaBitPackDecoder only supports Int32Type and Int64Type"),
}
}
#[inline]
fn subtract_u64(&self, left: i64, right: i64) -> u64 {
match T::get_physical_type() {
// Conversion of i32 -> u32 -> u64 is to avoid non-zero left most bytes in int repr
Type::INT32 => (left as i32).wrapping_sub(right as i32) as u32 as u64,
Type::INT64 => left.wrapping_sub(right) as u64,
_ => panic!("DeltaBitPackDecoder only supports Int32Type and Int64Type"),
}
}
}
// ----------------------------------------------------------------------
// DELTA_LENGTH_BYTE_ARRAY encoding
/// Encoding for byte arrays to separate the length values and the data.
/// The lengths are encoded using DELTA_BINARY_PACKED encoding, data is
/// stored as raw bytes.
pub struct DeltaLengthByteArrayEncoder<T: DataType> {
// length encoder
len_encoder: DeltaBitPackEncoder<Int32Type>,
// byte array data
data: Vec<ByteArray>,
// data size in bytes of encoded values
encoded_size: usize,
_phantom: PhantomData<T>,
}
impl<T: DataType> DeltaLengthByteArrayEncoder<T> {
/// Creates new delta length byte array encoder.
pub fn new() -> Self {
Self {
len_encoder: DeltaBitPackEncoder::new(),
data: vec![],
encoded_size: 0,
_phantom: PhantomData,
}
}
}
impl<T: DataType> Encoder<T> for DeltaLengthByteArrayEncoder<T> {
fn put(&mut self, values: &[T::T]) -> Result<()> {
ensure_phys_ty!(
Type::BYTE_ARRAY | Type::FIXED_LEN_BYTE_ARRAY,
"DeltaLengthByteArrayEncoder only supports ByteArrayType"
);
let val_it = || {
values
.iter()
.map(|x| x.as_any().downcast_ref::<ByteArray>().unwrap())
};
let lengths: Vec<i32> =
val_it().map(|byte_array| byte_array.len() as i32).collect();
self.len_encoder.put(&lengths)?;
for byte_array in val_it() {
self.encoded_size += byte_array.len();
self.data.push(byte_array.clone());
}
Ok(())
}
// Performance Note:
// As far as can be seen these functions are rarely called and as such we can hint to the
// compiler that they dont need to be folded into hot locations in the final output.
#[cold]
fn encoding(&self) -> Encoding {
Encoding::DELTA_LENGTH_BYTE_ARRAY
}
fn estimated_data_encoded_size(&self) -> usize {
self.len_encoder.estimated_data_encoded_size() + self.encoded_size
}
fn flush_buffer(&mut self) -> Result<ByteBufferPtr> {
ensure_phys_ty!(
Type::BYTE_ARRAY | Type::FIXED_LEN_BYTE_ARRAY,
"DeltaLengthByteArrayEncoder only supports ByteArrayType"
);
let mut total_bytes = vec![];
let lengths = self.len_encoder.flush_buffer()?;
total_bytes.extend_from_slice(lengths.data());
self.data.iter().for_each(|byte_array| {
total_bytes.extend_from_slice(byte_array.data());
});
self.data.clear();
self.encoded_size = 0;
Ok(ByteBufferPtr::new(total_bytes))
}
}
// ----------------------------------------------------------------------
// DELTA_BYTE_ARRAY encoding
/// Encoding for byte arrays, prefix lengths are encoded using DELTA_BINARY_PACKED
/// encoding, followed by suffixes with DELTA_LENGTH_BYTE_ARRAY encoding.
pub struct DeltaByteArrayEncoder<T: DataType> {
prefix_len_encoder: DeltaBitPackEncoder<Int32Type>,
suffix_writer: DeltaLengthByteArrayEncoder<ByteArrayType>,
previous: Vec<u8>,
_phantom: PhantomData<T>,
}
impl<T: DataType> DeltaByteArrayEncoder<T> {
/// Creates new delta byte array encoder.
pub fn new() -> Self {
Self {
prefix_len_encoder: DeltaBitPackEncoder::new(),
suffix_writer: DeltaLengthByteArrayEncoder::new(),
previous: vec![],
_phantom: PhantomData,
}
}
}
impl<T: DataType> Encoder<T> for DeltaByteArrayEncoder<T> {
fn put(&mut self, values: &[T::T]) -> Result<()> {
let mut prefix_lengths: Vec<i32> = vec![];
let mut suffixes: Vec<ByteArray> = vec![];
let values = values.iter()
.map(|x| x.as_any())
.map(|x| match T::get_physical_type() {
Type::BYTE_ARRAY => x.downcast_ref::<ByteArray>().unwrap(),
Type::FIXED_LEN_BYTE_ARRAY => x.downcast_ref::<FixedLenByteArray>().unwrap(),
_ => panic!(
"DeltaByteArrayEncoder only supports ByteArrayType and FixedLenByteArrayType"
)
});
for byte_array in values {
let current = byte_array.data();
// Maximum prefix length that is shared between previous value and current
// value
let prefix_len = cmp::min(self.previous.len(), current.len());
let mut match_len = 0;
while match_len < prefix_len && self.previous[match_len] == current[match_len]
{
match_len += 1;
}
prefix_lengths.push(match_len as i32);
suffixes.push(byte_array.slice(match_len, byte_array.len() - match_len));
// Update previous for the next prefix
self.previous.clear();
self.previous.extend_from_slice(current);
}
self.prefix_len_encoder.put(&prefix_lengths)?;
self.suffix_writer.put(&suffixes)?;
Ok(())
}
// Performance Note:
// As far as can be seen these functions are rarely called and as such we can hint to the
// compiler that they dont need to be folded into hot locations in the final output.
#[cold]
fn encoding(&self) -> Encoding {
Encoding::DELTA_BYTE_ARRAY
}
fn estimated_data_encoded_size(&self) -> usize {
self.prefix_len_encoder.estimated_data_encoded_size()
+ self.suffix_writer.estimated_data_encoded_size()
}
fn flush_buffer(&mut self) -> Result<ByteBufferPtr> {
match T::get_physical_type() {
Type::BYTE_ARRAY | Type::FIXED_LEN_BYTE_ARRAY => {
// TODO: investigate if we can merge lengths and suffixes
// without copying data into new vector.
let mut total_bytes = vec![];
// Insert lengths ...
let lengths = self.prefix_len_encoder.flush_buffer()?;
total_bytes.extend_from_slice(lengths.data());
// ... followed by suffixes
let suffixes = self.suffix_writer.flush_buffer()?;
total_bytes.extend_from_slice(suffixes.data());
self.previous.clear();
Ok(ByteBufferPtr::new(total_bytes))
}
_ => panic!(
"DeltaByteArrayEncoder only supports ByteArrayType and FixedLenByteArrayType"
)
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use std::sync::Arc;
use crate::encodings::decoding::{get_decoder, Decoder, DictDecoder, PlainDecoder};
use crate::schema::types::{
ColumnDescPtr, ColumnDescriptor, ColumnPath, Type as SchemaType,
};
use crate::util::test_common::{random_bytes, RandGen};
const TEST_SET_SIZE: usize = 1024;
#[test]
fn test_get_encoders() {
// supported encodings
create_and_check_encoder::<Int32Type>(Encoding::PLAIN, None);
create_and_check_encoder::<Int32Type>(Encoding::DELTA_BINARY_PACKED, None);
create_and_check_encoder::<Int32Type>(Encoding::DELTA_LENGTH_BYTE_ARRAY, None);
create_and_check_encoder::<Int32Type>(Encoding::DELTA_BYTE_ARRAY, None);
create_and_check_encoder::<BoolType>(Encoding::RLE, None);
// error when initializing
create_and_check_encoder::<Int32Type>(
Encoding::RLE_DICTIONARY,
Some(general_err!(
"Cannot initialize this encoding through this function"
)),
);
create_and_check_encoder::<Int32Type>(
Encoding::PLAIN_DICTIONARY,
Some(general_err!(
"Cannot initialize this encoding through this function"
)),
);
// unsupported
create_and_check_encoder::<Int32Type>(
Encoding::BIT_PACKED,
Some(nyi_err!("Encoding BIT_PACKED is not supported")),
);
}
#[test]
fn test_bool() {
BoolType::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
BoolType::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
BoolType::test(Encoding::RLE, TEST_SET_SIZE, -1);
}
#[test]
fn test_i32() {
Int32Type::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
Int32Type::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
Int32Type::test(Encoding::DELTA_BINARY_PACKED, TEST_SET_SIZE, -1);
}
#[test]
fn test_i64() {
Int64Type::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
Int64Type::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
Int64Type::test(Encoding::DELTA_BINARY_PACKED, TEST_SET_SIZE, -1);
}
#[test]
fn test_i96() {
Int96Type::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
Int96Type::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
}
#[test]
fn test_float() {
FloatType::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
FloatType::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
}
#[test]
fn test_double() {
DoubleType::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
DoubleType::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
}
#[test]
fn test_byte_array() {
ByteArrayType::test(Encoding::PLAIN, TEST_SET_SIZE, -1);
ByteArrayType::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, -1);
ByteArrayType::test(Encoding::DELTA_LENGTH_BYTE_ARRAY, TEST_SET_SIZE, -1);
ByteArrayType::test(Encoding::DELTA_BYTE_ARRAY, TEST_SET_SIZE, -1);
}
#[test]
fn test_fixed_lenbyte_array() {
FixedLenByteArrayType::test(Encoding::PLAIN, TEST_SET_SIZE, 100);
FixedLenByteArrayType::test(Encoding::PLAIN_DICTIONARY, TEST_SET_SIZE, 100);
FixedLenByteArrayType::test(Encoding::DELTA_BYTE_ARRAY, TEST_SET_SIZE, 100);
}
#[test]
fn test_dict_encoded_size() {
fn run_test<T: DataType>(
type_length: i32,
values: &[T::T],
expected_size: usize,
) {
let mut encoder = create_test_dict_encoder::<T>(type_length);
assert_eq!(encoder.dict_encoded_size(), 0);
encoder.put(values).unwrap();
assert_eq!(encoder.dict_encoded_size(), expected_size);
// We do not reset encoded size of the dictionary keys after flush_buffer
encoder.flush_buffer().unwrap();
assert_eq!(encoder.dict_encoded_size(), expected_size);
}
// Only 2 variations of values 1 byte each
run_test::<BoolType>(-1, &[true, false, true, false, true], 2);
run_test::<Int32Type>(-1, &[1i32, 2i32, 3i32, 4i32, 5i32], 20);
run_test::<Int64Type>(-1, &[1i64, 2i64, 3i64, 4i64, 5i64], 40);
run_test::<FloatType>(-1, &[1f32, 2f32, 3f32, 4f32, 5f32], 20);
run_test::<DoubleType>(-1, &[1f64, 2f64, 3f64, 4f64, 5f64], 40);
// Int96: len + reference
run_test::<Int96Type>(
-1,
&[Int96::from(vec![1, 2, 3]), Int96::from(vec![2, 3, 4])],
32,
);
run_test::<ByteArrayType>(
-1,
&[ByteArray::from("abcd"), ByteArray::from("efj")],
15,
);
run_test::<FixedLenByteArrayType>(
2,
&[ByteArray::from("ab").into(), ByteArray::from("bc").into()],
4,
);
}
#[test]
fn test_estimated_data_encoded_size() {
fn run_test<T: DataType>(
encoding: Encoding,
type_length: i32,
values: &[T::T],
initial_size: usize,
max_size: usize,
flush_size: usize,
) {
let mut encoder = match encoding {
Encoding::PLAIN_DICTIONARY | Encoding::RLE_DICTIONARY => {
Box::new(create_test_dict_encoder::<T>(type_length))
}
_ => create_test_encoder::<T>(type_length, encoding),
};
assert_eq!(encoder.estimated_data_encoded_size(), initial_size);
encoder.put(values).unwrap();
assert_eq!(encoder.estimated_data_encoded_size(), max_size);
encoder.flush_buffer().unwrap();
assert_eq!(encoder.estimated_data_encoded_size(), flush_size);
}
// PLAIN
run_test::<Int32Type>(Encoding::PLAIN, -1, &[123; 1024], 0, 4096, 0);
// DICTIONARY
// NOTE: The final size is almost the same because the dictionary entries are
// preserved after encoded values have been written.
run_test::<Int32Type>(Encoding::RLE_DICTIONARY, -1, &[123, 1024], 11, 68, 66);
// DELTA_BINARY_PACKED
run_test::<Int32Type>(Encoding::DELTA_BINARY_PACKED, -1, &[123; 1024], 0, 35, 0);
// RLE
let mut values = vec![];
values.extend_from_slice(&[true; 16]);
values.extend_from_slice(&[false; 16]);
run_test::<BoolType>(Encoding::RLE, -1, &values, 0, 6, 0);
// DELTA_LENGTH_BYTE_ARRAY
run_test::<ByteArrayType>(
Encoding::DELTA_LENGTH_BYTE_ARRAY,
-1,
&[ByteArray::from("ab"), ByteArray::from("abc")],
0,
5, // only value bytes, length encoder is not flushed yet
0,
);
// DELTA_BYTE_ARRAY
run_test::<ByteArrayType>(
Encoding::DELTA_BYTE_ARRAY,
-1,
&[ByteArray::from("ab"), ByteArray::from("abc")],
0,
3, // only suffix bytes, length encoder is not flushed yet
0,
);
}
// See: https://github.com/sunchao/parquet-rs/issues/47
#[test]
fn test_issue_47() {
let mut encoder =
create_test_encoder::<ByteArrayType>(0, Encoding::DELTA_BYTE_ARRAY);
let mut decoder =
create_test_decoder::<ByteArrayType>(0, Encoding::DELTA_BYTE_ARRAY);
let input = vec![
ByteArray::from("aa"),
ByteArray::from("aaa"),
ByteArray::from("aa"),
ByteArray::from("aaa"),
];
let mut output = vec![ByteArray::default(); input.len()];
let mut result =
put_and_get(&mut encoder, &mut decoder, &input[..2], &mut output[..2]);
assert!(
result.is_ok(),
"first put_and_get() failed with: {}",
result.unwrap_err()
);
result = put_and_get(&mut encoder, &mut decoder, &input[2..], &mut output[2..]);
assert!(
result.is_ok(),
"second put_and_get() failed with: {}",
result.unwrap_err()
);
assert_eq!(output, input);
}
trait EncodingTester<T: DataType> {
fn test(enc: Encoding, total: usize, type_length: i32) {
let result = match enc {
Encoding::PLAIN_DICTIONARY | Encoding::RLE_DICTIONARY => {
Self::test_dict_internal(total, type_length)
}
enc => Self::test_internal(enc, total, type_length),
};
assert!(
result.is_ok(),
"Expected result to be OK but got err:\n {}",
result.unwrap_err()
);
}
fn test_internal(enc: Encoding, total: usize, type_length: i32) -> Result<()>;
fn test_dict_internal(total: usize, type_length: i32) -> Result<()>;
}
impl<T: DataType + RandGen<T>> EncodingTester<T> for T {
fn test_internal(enc: Encoding, total: usize, type_length: i32) -> Result<()> {
let mut encoder = create_test_encoder::<T>(type_length, enc);
let mut decoder = create_test_decoder::<T>(type_length, enc);
let mut values = <T as RandGen<T>>::gen_vec(type_length, total);
let mut result_data = vec![T::T::default(); total];
// Test put/get spaced.
let num_bytes = bit_util::ceil(total as i64, 8);
let valid_bits = random_bytes(num_bytes as usize);
let values_written = encoder.put_spaced(&values[..], &valid_bits[..])?;
let data = encoder.flush_buffer()?;
decoder.set_data(data, values_written)?;
let _ = decoder.get_spaced(
&mut result_data[..],
values.len() - values_written,
&valid_bits[..],
)?;
// Check equality
for i in 0..total {
if bit_util::get_bit(&valid_bits[..], i) {
assert_eq!(result_data[i], values[i]);
} else {
assert_eq!(result_data[i], T::T::default());
}
}
let mut actual_total = put_and_get(
&mut encoder,
&mut decoder,
&values[..],
&mut result_data[..],
)?;
assert_eq!(actual_total, total);
assert_eq!(result_data, values);
// Encode more data after flush and test with decoder
values = <T as RandGen<T>>::gen_vec(type_length, total);
actual_total = put_and_get(
&mut encoder,
&mut decoder,
&values[..],
&mut result_data[..],
)?;
assert_eq!(actual_total, total);
assert_eq!(result_data, values);
Ok(())
}
fn test_dict_internal(total: usize, type_length: i32) -> Result<()> {
let mut encoder = create_test_dict_encoder::<T>(type_length);