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use std::{convert::TryFrom, fs::File, io::Read, path::Path, sync::Arc};
use parquet_format::{PageHeader, PageType};
use thrift::protocol::TCompactInputProtocol;
use crate::basic::{Compression, Encoding, Type};
use crate::column::page::{Page, PageReader};
use crate::compression::{create_codec, Codec};
use crate::errors::{ParquetError, Result};
use crate::file::{footer, metadata::*, reader::*, statistics};
use crate::record::reader::RowIter;
use crate::record::Row;
use crate::schema::types::Type as SchemaType;
use crate::util::{io::TryClone, memory::ByteBufferPtr};
pub use crate::util::{cursor::SliceableCursor, io::FileSource};
impl Length for File {
fn len(&self) -> u64 {
self.metadata().map(|m| m.len()).unwrap_or(0u64)
}
}
impl TryClone for File {
fn try_clone(&self) -> std::io::Result<Self> {
self.try_clone()
}
}
impl ChunkReader for File {
type T = FileSource<File>;
fn get_read(&self, start: u64, length: usize) -> Result<Self::T> {
Ok(FileSource::new(self, start, length))
}
}
impl Length for SliceableCursor {
fn len(&self) -> u64 {
SliceableCursor::len(self)
}
}
impl ChunkReader for SliceableCursor {
type T = SliceableCursor;
fn get_read(&self, start: u64, length: usize) -> Result<Self::T> {
self.slice(start, length).map_err(|e| e.into())
}
}
impl TryFrom<File> for SerializedFileReader<File> {
type Error = ParquetError;
fn try_from(file: File) -> Result<Self> {
Self::new(file)
}
}
impl<'a> TryFrom<&'a Path> for SerializedFileReader<File> {
type Error = ParquetError;
fn try_from(path: &Path) -> Result<Self> {
let file = File::open(path)?;
Self::try_from(file)
}
}
impl TryFrom<String> for SerializedFileReader<File> {
type Error = ParquetError;
fn try_from(path: String) -> Result<Self> {
Self::try_from(Path::new(&path))
}
}
impl<'a> TryFrom<&'a str> for SerializedFileReader<File> {
type Error = ParquetError;
fn try_from(path: &str) -> Result<Self> {
Self::try_from(Path::new(&path))
}
}
impl IntoIterator for SerializedFileReader<File> {
type Item = Row;
type IntoIter = RowIter<'static>;
fn into_iter(self) -> Self::IntoIter {
RowIter::from_file_into(Box::new(self))
}
}
pub struct SerializedFileReader<R: ChunkReader> {
chunk_reader: Arc<R>,
metadata: ParquetMetaData,
}
impl<R: 'static + ChunkReader> SerializedFileReader<R> {
pub fn new(chunk_reader: R) -> Result<Self> {
let metadata = footer::parse_metadata(&chunk_reader)?;
Ok(Self {
chunk_reader: Arc::new(chunk_reader),
metadata,
})
}
pub fn filter_row_groups(
&mut self,
predicate: &dyn Fn(&RowGroupMetaData, usize) -> bool,
) {
let mut filtered_row_groups = Vec::<RowGroupMetaData>::new();
for (i, row_group_metadata) in self.metadata.row_groups().iter().enumerate() {
if predicate(row_group_metadata, i) {
filtered_row_groups.push(row_group_metadata.clone());
}
}
self.metadata = ParquetMetaData::new(
self.metadata.file_metadata().clone(),
filtered_row_groups,
);
}
}
impl<R: 'static + ChunkReader> FileReader for SerializedFileReader<R> {
fn metadata(&self) -> &ParquetMetaData {
&self.metadata
}
fn num_row_groups(&self) -> usize {
self.metadata.num_row_groups()
}
fn get_row_group(&self, i: usize) -> Result<Box<dyn RowGroupReader + '_>> {
let row_group_metadata = self.metadata.row_group(i);
let f = Arc::clone(&self.chunk_reader);
Ok(Box::new(SerializedRowGroupReader::new(
f,
row_group_metadata,
)))
}
fn get_row_iter(&self, projection: Option<SchemaType>) -> Result<RowIter> {
RowIter::from_file(projection, self)
}
}
pub struct SerializedRowGroupReader<'a, R: ChunkReader> {
chunk_reader: Arc<R>,
metadata: &'a RowGroupMetaData,
}
impl<'a, R: ChunkReader> SerializedRowGroupReader<'a, R> {
fn new(chunk_reader: Arc<R>, metadata: &'a RowGroupMetaData) -> Self {
Self {
chunk_reader,
metadata,
}
}
}
impl<'a, R: 'static + ChunkReader> RowGroupReader for SerializedRowGroupReader<'a, R> {
fn metadata(&self) -> &RowGroupMetaData {
self.metadata
}
fn num_columns(&self) -> usize {
self.metadata.num_columns()
}
fn get_column_page_reader(&self, i: usize) -> Result<Box<dyn PageReader>> {
let col = self.metadata.column(i);
let (col_start, col_length) = col.byte_range();
let file_chunk = self.chunk_reader.get_read(col_start, col_length as usize)?;
let page_reader = SerializedPageReader::new(
file_chunk,
col.num_values(),
col.compression(),
col.column_descr().physical_type(),
)?;
Ok(Box::new(page_reader))
}
fn get_row_iter(&self, projection: Option<SchemaType>) -> Result<RowIter> {
RowIter::from_row_group(projection, self)
}
}
pub struct SerializedPageReader<T: Read> {
buf: T,
decompressor: Option<Box<dyn Codec>>,
seen_num_values: i64,
total_num_values: i64,
physical_type: Type,
}
impl<T: Read> SerializedPageReader<T> {
pub fn new(
buf: T,
total_num_values: i64,
compression: Compression,
physical_type: Type,
) -> Result<Self> {
let decompressor = create_codec(compression)?;
let result = Self {
buf,
total_num_values,
seen_num_values: 0,
decompressor,
physical_type,
};
Ok(result)
}
fn read_page_header(&mut self) -> Result<PageHeader> {
let mut prot = TCompactInputProtocol::new(&mut self.buf);
let page_header = PageHeader::read_from_in_protocol(&mut prot)?;
Ok(page_header)
}
}
impl<T: Read> Iterator for SerializedPageReader<T> {
type Item = Result<Page>;
fn next(&mut self) -> Option<Self::Item> {
self.get_next_page().transpose()
}
}
impl<T: Read> PageReader for SerializedPageReader<T> {
fn get_next_page(&mut self) -> Result<Option<Page>> {
while self.seen_num_values < self.total_num_values {
let page_header = self.read_page_header()?;
let mut offset: usize = 0;
let mut can_decompress = true;
if let Some(ref header_v2) = page_header.data_page_header_v2 {
offset = (header_v2.definition_levels_byte_length
+ header_v2.repetition_levels_byte_length)
as usize;
can_decompress = header_v2.is_compressed.unwrap_or(true);
}
let compressed_len = page_header.compressed_page_size as usize - offset;
let uncompressed_len = page_header.uncompressed_page_size as usize - offset;
let mut buffer = vec![0; offset + compressed_len];
self.buf.read_exact(&mut buffer)?;
if let Some(decompressor) = self.decompressor.as_mut() {
if can_decompress {
let mut decompressed_buffer = Vec::with_capacity(uncompressed_len);
let decompressed_size = decompressor
.decompress(&buffer[offset..], &mut decompressed_buffer)?;
if decompressed_size != uncompressed_len {
return Err(general_err!(
"Actual decompressed size doesn't match the expected one ({} vs {})",
decompressed_size,
uncompressed_len
));
}
if offset == 0 {
buffer = decompressed_buffer;
} else {
buffer.truncate(offset);
buffer.append(&mut decompressed_buffer);
}
}
}
let result = match page_header.type_ {
PageType::DictionaryPage => {
assert!(page_header.dictionary_page_header.is_some());
let dict_header =
page_header.dictionary_page_header.as_ref().unwrap();
let is_sorted = dict_header.is_sorted.unwrap_or(false);
Page::DictionaryPage {
buf: ByteBufferPtr::new(buffer),
num_values: dict_header.num_values as u32,
encoding: Encoding::from(dict_header.encoding),
is_sorted,
}
}
PageType::DataPage => {
assert!(page_header.data_page_header.is_some());
let header = page_header.data_page_header.unwrap();
self.seen_num_values += header.num_values as i64;
Page::DataPage {
buf: ByteBufferPtr::new(buffer),
num_values: header.num_values as u32,
encoding: Encoding::from(header.encoding),
def_level_encoding: Encoding::from(
header.definition_level_encoding,
),
rep_level_encoding: Encoding::from(
header.repetition_level_encoding,
),
statistics: statistics::from_thrift(
self.physical_type,
header.statistics,
),
}
}
PageType::DataPageV2 => {
assert!(page_header.data_page_header_v2.is_some());
let header = page_header.data_page_header_v2.unwrap();
let is_compressed = header.is_compressed.unwrap_or(true);
self.seen_num_values += header.num_values as i64;
Page::DataPageV2 {
buf: ByteBufferPtr::new(buffer),
num_values: header.num_values as u32,
encoding: Encoding::from(header.encoding),
num_nulls: header.num_nulls as u32,
num_rows: header.num_rows as u32,
def_levels_byte_len: header.definition_levels_byte_length as u32,
rep_levels_byte_len: header.repetition_levels_byte_length as u32,
is_compressed,
statistics: statistics::from_thrift(
self.physical_type,
header.statistics,
),
}
}
_ => {
continue;
}
};
return Ok(Some(result));
}
Ok(None)
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::basic::ColumnOrder;
use crate::record::RowAccessor;
use crate::schema::parser::parse_message_type;
use crate::util::test_common::{get_test_file, get_test_path};
use std::sync::Arc;
#[test]
fn test_cursor_and_file_has_the_same_behaviour() {
let mut buf: Vec<u8> = Vec::new();
get_test_file("alltypes_plain.parquet")
.read_to_end(&mut buf)
.unwrap();
let cursor = SliceableCursor::new(buf);
let read_from_cursor = SerializedFileReader::new(cursor).unwrap();
let test_file = get_test_file("alltypes_plain.parquet");
let read_from_file = SerializedFileReader::new(test_file).unwrap();
let file_iter = read_from_file.get_row_iter(None).unwrap();
let cursor_iter = read_from_cursor.get_row_iter(None).unwrap();
assert!(file_iter.eq(cursor_iter));
}
#[test]
fn test_file_reader_try_from() {
let test_file = get_test_file("alltypes_plain.parquet");
let test_path_buf = get_test_path("alltypes_plain.parquet");
let test_path = test_path_buf.as_path();
let test_path_str = test_path.to_str().unwrap();
let reader = SerializedFileReader::try_from(test_file);
assert!(reader.is_ok());
let reader = SerializedFileReader::try_from(test_path);
assert!(reader.is_ok());
let reader = SerializedFileReader::try_from(test_path_str);
assert!(reader.is_ok());
let reader = SerializedFileReader::try_from(test_path_str.to_string());
assert!(reader.is_ok());
let test_path = Path::new("invalid.parquet");
let test_path_str = test_path.to_str().unwrap();
let reader = SerializedFileReader::try_from(test_path);
assert!(reader.is_err());
let reader = SerializedFileReader::try_from(test_path_str);
assert!(reader.is_err());
let reader = SerializedFileReader::try_from(test_path_str.to_string());
assert!(reader.is_err());
}
#[test]
fn test_file_reader_into_iter() {
let path = get_test_path("alltypes_plain.parquet");
let vec = vec![path.clone(), path]
.iter()
.map(|p| SerializedFileReader::try_from(p.as_path()).unwrap())
.flat_map(|r| r.into_iter())
.flat_map(|r| r.get_int(0))
.collect::<Vec<_>>();
assert_eq!(vec, vec![4, 5, 6, 7, 2, 3, 0, 1, 4, 5, 6, 7, 2, 3, 0, 1]);
}
#[test]
fn test_file_reader_into_iter_project() {
let path = get_test_path("alltypes_plain.parquet");
let result = vec![path]
.iter()
.map(|p| SerializedFileReader::try_from(p.as_path()).unwrap())
.flat_map(|r| {
let schema = "message schema { OPTIONAL INT32 id; }";
let proj = parse_message_type(schema).ok();
r.into_iter().project(proj).unwrap()
})
.map(|r| format!("{}", r))
.collect::<Vec<_>>()
.join(",");
assert_eq!(
result,
"{id: 4},{id: 5},{id: 6},{id: 7},{id: 2},{id: 3},{id: 0},{id: 1}"
);
}
#[test]
fn test_reuse_file_chunk() {
let test_file = get_test_file("alltypes_plain.parquet");
let reader = SerializedFileReader::new(test_file).unwrap();
let row_group = reader.get_row_group(0).unwrap();
let mut page_readers = Vec::new();
for i in 0..row_group.num_columns() {
page_readers.push(row_group.get_column_page_reader(i).unwrap());
}
for mut page_reader in page_readers {
assert!(page_reader.get_next_page().is_ok());
}
}
#[test]
fn test_file_reader() {
let test_file = get_test_file("alltypes_plain.parquet");
let reader_result = SerializedFileReader::new(test_file);
assert!(reader_result.is_ok());
let reader = reader_result.unwrap();
let metadata = reader.metadata();
assert_eq!(metadata.num_row_groups(), 1);
let file_metadata = metadata.file_metadata();
assert!(file_metadata.created_by().is_some());
assert_eq!(
file_metadata.created_by().as_ref().unwrap(),
"impala version 1.3.0-INTERNAL (build 8a48ddb1eff84592b3fc06bc6f51ec120e1fffc9)"
);
assert!(file_metadata.key_value_metadata().is_none());
assert_eq!(file_metadata.num_rows(), 8);
assert_eq!(file_metadata.version(), 1);
assert_eq!(file_metadata.column_orders(), None);
let row_group_metadata = metadata.row_group(0);
assert_eq!(row_group_metadata.num_columns(), 11);
assert_eq!(row_group_metadata.num_rows(), 8);
assert_eq!(row_group_metadata.total_byte_size(), 671);
for i in 0..row_group_metadata.num_columns() {
assert_eq!(file_metadata.column_order(i), ColumnOrder::UNDEFINED);
}
let row_group_reader_result = reader.get_row_group(0);
assert!(row_group_reader_result.is_ok());
let row_group_reader: Box<dyn RowGroupReader> = row_group_reader_result.unwrap();
assert_eq!(
row_group_reader.num_columns(),
row_group_metadata.num_columns()
);
assert_eq!(
row_group_reader.metadata().total_byte_size(),
row_group_metadata.total_byte_size()
);
let page_reader_0_result = row_group_reader.get_column_page_reader(0);
assert!(page_reader_0_result.is_ok());
let mut page_reader_0: Box<dyn PageReader> = page_reader_0_result.unwrap();
let mut page_count = 0;
while let Ok(Some(page)) = page_reader_0.get_next_page() {
let is_expected_page = match page {
Page::DictionaryPage {
buf,
num_values,
encoding,
is_sorted,
} => {
assert_eq!(buf.len(), 32);
assert_eq!(num_values, 8);
assert_eq!(encoding, Encoding::PLAIN_DICTIONARY);
assert!(!is_sorted);
true
}
Page::DataPage {
buf,
num_values,
encoding,
def_level_encoding,
rep_level_encoding,
statistics,
} => {
assert_eq!(buf.len(), 11);
assert_eq!(num_values, 8);
assert_eq!(encoding, Encoding::PLAIN_DICTIONARY);
assert_eq!(def_level_encoding, Encoding::RLE);
assert_eq!(rep_level_encoding, Encoding::BIT_PACKED);
assert!(statistics.is_none());
true
}
_ => false,
};
assert!(is_expected_page);
page_count += 1;
}
assert_eq!(page_count, 2);
}
#[test]
fn test_file_reader_datapage_v2() {
let test_file = get_test_file("datapage_v2.snappy.parquet");
let reader_result = SerializedFileReader::new(test_file);
assert!(reader_result.is_ok());
let reader = reader_result.unwrap();
let metadata = reader.metadata();
assert_eq!(metadata.num_row_groups(), 1);
let file_metadata = metadata.file_metadata();
assert!(file_metadata.created_by().is_some());
assert_eq!(
file_metadata.created_by().as_ref().unwrap(),
"parquet-mr version 1.8.1 (build 4aba4dae7bb0d4edbcf7923ae1339f28fd3f7fcf)"
);
assert!(file_metadata.key_value_metadata().is_some());
assert_eq!(
file_metadata.key_value_metadata().to_owned().unwrap().len(),
1
);
assert_eq!(file_metadata.num_rows(), 5);
assert_eq!(file_metadata.version(), 1);
assert_eq!(file_metadata.column_orders(), None);
let row_group_metadata = metadata.row_group(0);
for i in 0..row_group_metadata.num_columns() {
assert_eq!(file_metadata.column_order(i), ColumnOrder::UNDEFINED);
}
let row_group_reader_result = reader.get_row_group(0);
assert!(row_group_reader_result.is_ok());
let row_group_reader: Box<dyn RowGroupReader> = row_group_reader_result.unwrap();
assert_eq!(
row_group_reader.num_columns(),
row_group_metadata.num_columns()
);
assert_eq!(
row_group_reader.metadata().total_byte_size(),
row_group_metadata.total_byte_size()
);
let page_reader_0_result = row_group_reader.get_column_page_reader(0);
assert!(page_reader_0_result.is_ok());
let mut page_reader_0: Box<dyn PageReader> = page_reader_0_result.unwrap();
let mut page_count = 0;
while let Ok(Some(page)) = page_reader_0.get_next_page() {
let is_expected_page = match page {
Page::DictionaryPage {
buf,
num_values,
encoding,
is_sorted,
} => {
assert_eq!(buf.len(), 7);
assert_eq!(num_values, 1);
assert_eq!(encoding, Encoding::PLAIN);
assert!(!is_sorted);
true
}
Page::DataPageV2 {
buf,
num_values,
encoding,
num_nulls,
num_rows,
def_levels_byte_len,
rep_levels_byte_len,
is_compressed,
statistics,
} => {
assert_eq!(buf.len(), 4);
assert_eq!(num_values, 5);
assert_eq!(encoding, Encoding::RLE_DICTIONARY);
assert_eq!(num_nulls, 1);
assert_eq!(num_rows, 5);
assert_eq!(def_levels_byte_len, 2);
assert_eq!(rep_levels_byte_len, 0);
assert!(is_compressed);
assert!(statistics.is_some());
true
}
_ => false,
};
assert!(is_expected_page);
page_count += 1;
}
assert_eq!(page_count, 2);
}
#[test]
fn test_page_iterator() {
let file = get_test_file("alltypes_plain.parquet");
let file_reader = Arc::new(SerializedFileReader::new(file).unwrap());
let mut page_iterator = FilePageIterator::new(0, file_reader.clone()).unwrap();
let page = page_iterator.next();
assert!(page.is_some());
assert!(page.unwrap().is_ok());
let page = page_iterator.next();
assert!(page.is_none());
let row_group_indices = Box::new(0..1);
let mut page_iterator =
FilePageIterator::with_row_groups(0, row_group_indices, file_reader).unwrap();
let page = page_iterator.next();
assert!(page.is_some());
assert!(page.unwrap().is_ok());
let page = page_iterator.next();
assert!(page.is_none());
}
#[test]
fn test_file_reader_key_value_metadata() {
let file = get_test_file("binary.parquet");
let file_reader = Arc::new(SerializedFileReader::new(file).unwrap());
let metadata = file_reader
.metadata
.file_metadata()
.key_value_metadata()
.as_ref()
.unwrap();
assert_eq!(metadata.len(), 3);
assert_eq!(metadata.get(0).unwrap().key, "parquet.proto.descriptor");
assert_eq!(metadata.get(1).unwrap().key, "writer.model.name");
assert_eq!(metadata.get(1).unwrap().value, Some("protobuf".to_owned()));
assert_eq!(metadata.get(2).unwrap().key, "parquet.proto.class");
assert_eq!(
metadata.get(2).unwrap().value,
Some("foo.baz.Foobaz$Event".to_owned())
);
}
#[test]
fn test_file_reader_filter_row_groups() -> Result<()> {
let test_file = get_test_file("alltypes_plain.parquet");
let mut reader = SerializedFileReader::new(test_file)?;
let metadata = reader.metadata();
assert_eq!(metadata.num_row_groups(), 1);
reader.filter_row_groups(&|_, _| false);
let metadata = reader.metadata();
assert_eq!(metadata.num_row_groups(), 0);
Ok(())
}
}