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| #define BOOST_STACKTRACE_USE_BACKTRACE
#include <arrow/buffer.h>
#include <arrow/io/api.h>
#include <arrow/result.h>
#include <arrow/status.h>
#include <arrow/util/macros.h>
#include <arrow/util/rle_encoding.h>
#include <thrift/TApplicationException.h>
#include <thrift/protocol/TBinaryProtocol.h>
#include <thrift/protocol/TCompactProtocol.h>
#include <thrift/protocol/TDebugProtocol.h>
#include <thrift/protocol/TJSONProtocol.h>
#include <thrift/transport/TBufferTransports.h>
#include <boost/stacktrace.hpp>
#include <iostream>
#include <sstream>
#include <string>
#include "gen-cpp/parquet_types.h"
static constexpr size_t kDefaultPageHeaderSize = 16 * 1024;
static constexpr size_t kMaxPageHeaderSize = 16 * 1024 * 1024;
#define ASSERT_TRUE(expr) \
if (!(expr)) { \
std::stringstream ss; \
ss << "Assertion '" << #expr << "' failed (" << __FILE__ << ":" << __LINE__ << ")"; \
return arrow::Status::ExecutionError(ss.str()); \
}
class ParquetNativeReader {
public:
ParquetNativeReader(const std::string& path) {
auto status = arrow::io::ReadableFile::Open(path, arrow::default_memory_pool()).Value(&_file);
if (!status.ok()) {
throw std::invalid_argument("wrong file path");
}
}
arrow::Status parse() {
ARROW_RETURN_NOT_OK(parse_footer());
ARROW_RETURN_NOT_OK(parse_data());
return arrow::Status::OK();
}
private:
class Dictionary {
public:
void take_over(std::shared_ptr<arrow::Buffer>&& buffer) { this->_buffer = buffer; }
void add(const void* value) { _dictionaries.push_back(value); }
const void* get(size_t idx) const { return _dictionaries[idx]; }
private:
std::shared_ptr<arrow::Buffer> _buffer;
std::vector<const void*> _dictionaries;
};
struct ColumnData {
ColumnData(std::vector<uint32_t>&& repetition_levels_, std::vector<uint32_t>&& definition_levels_,
std::vector<std::string>&& values_)
: repetition_levels(std::move(repetition_levels_)),
definition_levels(std::move(definition_levels_)),
values(std::move(values_)) {}
const std::vector<uint32_t> repetition_levels;
const std::vector<uint32_t> definition_levels;
const std::vector<std::string> values;
};
struct TreeElement {
TreeElement(const std::string full_name_, const parquet::SchemaElement element_, TreeElement* const parent_)
: full_name(full_name_), element(element_), parent(parent_) {}
std::vector<const TreeElement*> ancestors() const {
std::vector<const TreeElement*> ancestors;
const TreeElement* cur = this;
while (cur) {
ancestors.push_back(cur);
cur = cur->parent;
}
std::reverse(ancestors.begin(), ancestors.end());
return ancestors;
}
const std::string full_name;
const parquet::SchemaElement element;
TreeElement* const parent;
std::vector<TreeElement*> children;
uint32_t max_repetition_level;
uint32_t max_definition_level;
std::shared_ptr<ColumnData> data;
};
class StructuredData {
public:
static arrow::Result<std::shared_ptr<StructuredData>> build(const std::vector<TreeElement*>& leafs) {
auto root = std::make_shared<StructuredData>(true, nullptr);
for (const auto& leaf : leafs) {
ARROW_RETURN_NOT_OK(root->feed_column_data(leaf, leaf->data.get()));
}
return root;
}
StructuredData(const bool is_root_, const TreeElement* element_) : _is_root(is_root_), _element(element_) {}
size_t repetition_num() const { return _nested_repetitions.size(); }
const auto& get_repetition(const size_t repetition_idx) const { return _nested_repetitions[repetition_idx]; }
std::vector<StructuredData*> get_ordered_nested_fields(const size_t repetition_idx) const {
std::vector<StructuredData*> ordered_nested_fields;
const auto& nested_repetition = _nested_repetitions[repetition_idx];
for (const auto* child_element : _element->children) {
const auto& name = child_element->element.name;
if (auto it = nested_repetition.find(name); it != nested_repetition.end()) {
ordered_nested_fields.push_back(it->second.get());
}
}
return ordered_nested_fields;
}
arrow::Status insert_value_to_tree(const std::string& value,
const std::vector<size_t>& layer_idx_2_next_repetition_idx,
const std::vector<const TreeElement*>& ancestors,
const size_t start_layer_idx) {
StructuredData* cur = this;
for (size_t layer_idx = start_layer_idx; layer_idx < ancestors.size(); ++layer_idx) {
const auto name = ancestors[layer_idx]->element.name;
const auto next_repetition_idx = layer_idx_2_next_repetition_idx[layer_idx];
if (cur->_nested_repetitions.size() <= next_repetition_idx) {
cur->_nested_repetitions.emplace_back();
}
if (cur->_nested_repetitions[next_repetition_idx].find(name) ==
cur->_nested_repetitions[next_repetition_idx].end()) {
cur->_nested_repetitions[next_repetition_idx][name] =
std::make_shared<StructuredData>(false, ancestors[layer_idx]);
}
cur = cur->_nested_repetitions[next_repetition_idx][name].get();
}
cur->_values.push_back(value);
return arrow::Status::OK();
}
arrow::Status feed_column_data(TreeElement* element, const ColumnData* data) {
ASSERT_TRUE(_is_root);
const auto ancestors = element->ancestors();
std::vector<size_t> layer_idx_2_next_repetition_idx(ancestors.size(), 0);
std::vector<size_t> repeat_level_2_layer_idx;
repeat_level_2_layer_idx.push_back(0);
for (size_t layer = 0; layer < ancestors.size(); ++layer) {
const auto ancestor = ancestors[layer];
if (ancestor->element.repetition_type == parquet::FieldRepetitionType::REPEATED) {
repeat_level_2_layer_idx.push_back(layer);
}
}
for (size_t i = 0; i < data->values.size(); ++i) {
const auto repetition_level = data->repetition_levels[i];
[[maybe_unused]] const auto definition_level = data->definition_levels[i];
const auto& value = data->values[i];
const auto start_layer_idx = repeat_level_2_layer_idx[repetition_level];
StructuredData* cur = this;
for (size_t layer_idx = 0; layer_idx < start_layer_idx; ++layer_idx) {
const auto& name = ancestors[layer_idx]->element.name;
ASSERT_TRUE(layer_idx_2_next_repetition_idx[layer_idx] >= 1);
const auto latest_repetition_idx = layer_idx_2_next_repetition_idx[layer_idx] - 1;
ASSERT_TRUE(cur->_nested_repetitions[latest_repetition_idx].find(name) !=
cur->_nested_repetitions[latest_repetition_idx].end());
cur = cur->_nested_repetitions[latest_repetition_idx][name].get();
}
for (size_t layer_idx = start_layer_idx + 1; layer_idx < layer_idx_2_next_repetition_idx.size();
++layer_idx) {
layer_idx_2_next_repetition_idx[layer_idx] = 0;
}
ARROW_RETURN_NOT_OK(
cur->insert_value_to_tree(value, layer_idx_2_next_repetition_idx, ancestors, start_layer_idx));
for (size_t layer_idx = start_layer_idx; layer_idx < layer_idx_2_next_repetition_idx.size();
++layer_idx) {
layer_idx_2_next_repetition_idx[layer_idx]++;
}
}
return arrow::Status::OK();
}
arrow::Status to_pretty_string(std::stringstream& buffer, const std::string indent = "") const {
buffer << indent << _element->element.name << ": \n";
if (!_nested_repetitions.empty()) {
ASSERT_TRUE(_values.empty());
for (size_t repetition_idx = 0; repetition_idx < repetition_num(); ++repetition_idx) {
for (const auto* nested_field : get_ordered_nested_fields(repetition_idx)) {
ARROW_RETURN_NOT_OK(nested_field->to_pretty_string(buffer, indent + " "));
}
}
} else {
for (const auto& value : _values) {
buffer << indent << " " << value << "\n";
}
}
return arrow::Status::OK();
}
private:
const bool _is_root;
const TreeElement* _element;
using FiledNameToNestedStructuredData = std::unordered_map<std::string, std::shared_ptr<StructuredData>>;
std::vector<FiledNameToNestedStructuredData> _nested_repetitions;
std::vector<std::string> _values;
};
arrow::Status parse_footer() {
ARROW_ASSIGN_OR_RAISE(_file_size, _file->GetSize());
reset_indent();
print("Footer:");
increase_indent();
uint64_t pos = _file_size;
ARROW_ASSIGN_OR_RAISE(auto buffer, _file->ReadAt(pos - 4, 4));
print("magic number: ", buffer->data_as<char>());
pos -= 4;
ARROW_ASSIGN_OR_RAISE(buffer, _file->ReadAt(pos - 4, 4));
const auto footer_length = *buffer->data_as<int32_t>();
print("file metadata length: ", footer_length);
pos -= 4;
ARROW_ASSIGN_OR_RAISE(buffer, _file->ReadAt(pos - footer_length, footer_length));
pos -= footer_length;
try {
std::shared_ptr<apache::thrift::transport::TMemoryBuffer> t_mem_buffer(
new apache::thrift::transport::TMemoryBuffer(const_cast<uint8_t*>(buffer->data()), footer_length));
apache::thrift::protocol::TCompactProtocolFactoryT<apache::thrift::transport::TMemoryBuffer>
t_proto_factory;
std::shared_ptr<apache::thrift::protocol::TProtocol> t_proto = t_proto_factory.getProtocol(t_mem_buffer);
_file_metadata.read(t_proto.get());
} catch (const apache::thrift::TException& te) {
std::cerr << "Thrift exception: " << te.what() << std::endl;
return arrow::Status::IOError("Failed to deserialize Parquet metadata.");
}
print("num_rows: ", _file_metadata.num_rows);
for (size_t i = 0; i < _file_metadata.row_groups.size(); ++i) {
const auto& row_group = _file_metadata.row_groups[i];
print("row group: ", i);
increase_indent();
if (row_group.__isset.file_offset) print("file_offset: ", row_group.file_offset);
print("total_byte_size: ", row_group.total_byte_size);
if (row_group.__isset.total_compressed_size)
print("total_compressed_size: ", row_group.total_compressed_size);
for (size_t j = 0; j < row_group.columns.size(); ++j) {
const auto& column = row_group.columns[j];
const auto& meta_data = column.meta_data;
print("column: ", j);
increase_indent();
if (column.__isset.file_path) print("file_path: ", column.file_path);
print("file_offset: ", column.file_offset);
print("type: ", meta_data.type);
print("path_in_schema: ", vector_to_string(column.meta_data.path_in_schema));
print("encodings: ", vector_to_string(meta_data.encodings));
print("codec: ", meta_data.codec);
print("num_values: ", meta_data.num_values);
print("total_compressed_size: ", meta_data.total_compressed_size);
print("total_uncompressed_size: ", meta_data.total_uncompressed_size);
print("data_page_offset: ", meta_data.data_page_offset);
if (meta_data.__isset.dictionary_page_offset)
print("dictionary_page_offset: ", meta_data.dictionary_page_offset);
if (meta_data.__isset.index_page_offset) print("index_page_offset: ", meta_data.index_page_offset);
if (meta_data.__isset.bloom_filter_offset)
print("bloom_filter_offset: ", meta_data.bloom_filter_offset);
if (meta_data.__isset.bloom_filter_length)
print("bloom_filter_length: ", meta_data.bloom_filter_length);
decrease_indent();
}
decrease_indent();
}
decrease_indent();
ARROW_RETURN_NOT_OK(parseTreeElements());
return arrow::Status::OK();
}
arrow::Status parseTreeElements() {
ASSERT_TRUE(!_file_metadata.schema.empty());
print("Column levels:");
increase_indent();
ASSERT_TRUE(_file_metadata.schema.front().name == "schema");
auto it = _file_metadata.schema.begin();
std::vector<std::string> paths;
uint32_t max_repetition_level = 0;
uint32_t max_definition_level = 0;
std::function<void(TreeElement * parent, std::vector<parquet::SchemaElement>::iterator & it,
std::vector<std::string> & paths, uint32_t & max_repetition_level,
uint32_t & max_definition_level)>
depth_first_visit;
depth_first_visit = [this, &depth_first_visit](TreeElement* parent,
std::vector<parquet::SchemaElement>::iterator& it,
std::vector<std::string>& paths, uint32_t& max_repetition_level,
uint32_t& max_definition_level) -> void {
const auto& element = *it;
const bool is_repeated = (element.repetition_type == parquet::FieldRepetitionType::REPEATED);
const bool is_optional =
(element.repetition_type == parquet::FieldRepetitionType::OPTIONAL ||
(element.__isset.converted_type && element.converted_type == parquet::ConvertedType::LIST));
it++;
paths.push_back(element.name);
if (is_repeated) max_repetition_level++;
if (is_optional) max_definition_level++;
const auto unified_column_name = vector_to_string(paths, false, ".");
auto cur = std::make_shared<TreeElement>(unified_column_name, element, parent);
if (parent) parent->children.push_back(cur.get());
_schema[unified_column_name] = cur;
if (!element.__isset.num_children) {
_leafs.push_back(cur.get());
cur->max_repetition_level = max_repetition_level;
cur->max_definition_level = max_definition_level;
print("column path: ", unified_column_name);
increase_indent();
print("max repetition level: ", max_repetition_level);
print("max definition level: ", max_definition_level);
decrease_indent();
} else {
for (int32_t child = 0; child < element.num_children; ++child) {
depth_first_visit(cur.get(), it, paths, max_repetition_level, max_definition_level);
}
}
if (is_optional) max_definition_level--;
if (is_repeated) max_repetition_level--;
paths.pop_back();
};
depth_first_visit(nullptr, it, paths, max_repetition_level, max_definition_level);
return arrow::Status::OK();
}
arrow::Status parse_data() {
reset_indent();
print("Data:");
increase_indent();
for (size_t i = 0; i < _file_metadata.row_groups.size(); ++i) {
print("row group: ", i);
increase_indent();
const auto& row_group = _file_metadata.row_groups[i];
for (size_t j = 0; j < row_group.columns.size(); ++j) {
const auto& column = row_group.columns[j];
const auto& meta_data = column.meta_data;
const auto& unified_column_name = get_unified_column_name(column);
print("column: ", unified_column_name);
increase_indent();
if (meta_data.total_compressed_size != meta_data.total_uncompressed_size) {
return arrow::Status::NotImplemented("Only support uncompressed column");
}
int64_t remain = meta_data.total_uncompressed_size;
if (!meta_data.__isset.dictionary_page_offset) {
return arrow::Status::NotImplemented("Only support dictionary");
}
Dictionary dictionary;
{
parquet::PageHeader page_header;
ARROW_ASSIGN_OR_RAISE(const auto page_header_length,
parse_page_header(meta_data.dictionary_page_offset, &page_header));
ARROW_ASSIGN_OR_RAISE(dictionary,
parse_dictionary_page(meta_data.dictionary_page_offset + page_header_length,
page_header, column));
remain -= page_header_length;
remain -= page_header.uncompressed_page_size;
}
parquet::PageHeader page_header;
ARROW_ASSIGN_OR_RAISE(const auto page_header_length,
parse_page_header(meta_data.data_page_offset, &page_header));
ARROW_ASSIGN_OR_RAISE(auto data, parse_data_page(meta_data.data_page_offset + page_header_length,
page_header, column, dictionary));
_schema[unified_column_name]->data = std::move(data);
remain -= page_header_length;
remain -= page_header.uncompressed_page_size;
ASSERT_TRUE(remain == 0);
decrease_indent();
}
ARROW_RETURN_NOT_OK(pretty_print_row_group());
decrease_indent();
}
return arrow::Status::OK();
}
arrow::Result<uint64_t> parse_page_header(const uint64_t offset, parquet::PageHeader* page_header) {
const auto page_header_length = std::min(kDefaultPageHeaderSize, _file_size - offset);
ARROW_ASSIGN_OR_RAISE(auto buffer, _file->ReadAt(offset, page_header_length));
try {
std::shared_ptr<apache::thrift::transport::TMemoryBuffer> t_mem_buffer(
new apache::thrift::transport::TMemoryBuffer(const_cast<uint8_t*>(buffer->data()),
page_header_length));
apache::thrift::protocol::TCompactProtocolFactoryT<apache::thrift::transport::TMemoryBuffer>
t_proto_factory;
std::shared_ptr<apache::thrift::protocol::TProtocol> t_proto = t_proto_factory.getProtocol(t_mem_buffer);
page_header->read(t_proto.get());
return page_header_length - t_mem_buffer->available_read();
} catch (const apache::thrift::TException& te) {
std::cerr << "Thrift exception: " << te.what() << std::endl;
return arrow::Status::IOError("Failed to deserialize Parquet data page header.");
}
}
arrow::Result<Dictionary> parse_dictionary_page(const uint64_t offset, const parquet::PageHeader& page_header,
const parquet::ColumnChunk& column) {
if (page_header.dictionary_page_header.encoding != parquet::Encoding::PLAIN) {
return arrow::Status::NotImplemented("Only support PLAIN encoding dictionary page");
}
if (page_header.compressed_page_size != page_header.uncompressed_page_size) {
return arrow::Status::NotImplemented("Only support uncompressed dictionary page");
}
Dictionary dictionary;
std::shared_ptr<arrow::Buffer> buffer;
if (column.meta_data.type == parquet::Type::INT64) {
ARROW_ASSIGN_OR_RAISE(buffer, _file->ReadAt(offset, page_header.uncompressed_page_size));
const uint8_t* data = buffer->data();
for (int32_t i = 0; i < page_header.dictionary_page_header.num_values; ++i) {
dictionary.add(reinterpret_cast<const void*>(data + sizeof(int64_t) * i));
}
} else if (column.meta_data.type == parquet::Type::DOUBLE) {
ARROW_ASSIGN_OR_RAISE(buffer, _file->ReadAt(offset, page_header.uncompressed_page_size));
const uint8_t* data = buffer->data();
for (int32_t i = 0; i < page_header.dictionary_page_header.num_values; ++i) {
dictionary.add(reinterpret_cast<const void*>(data + sizeof(double) * i));
}
} else if (column.meta_data.type == parquet::Type::BYTE_ARRAY) {
ARROW_ASSIGN_OR_RAISE(buffer, _file->ReadAt(offset, page_header.uncompressed_page_size));
const uint8_t* data = buffer->data();
size_t offset = 0;
for (int32_t i = 0; i < page_header.dictionary_page_header.num_values; ++i) {
const auto length = *reinterpret_cast<const uint32_t*>(data + offset);
dictionary.add(reinterpret_cast<const void*>(data + offset));
offset += sizeof(uint32_t) + length;
}
}
dictionary.take_over(std::move(buffer));
return dictionary;
}
arrow::Result<std::shared_ptr<ColumnData>> parse_data_page(const uint64_t offset,
const parquet::PageHeader& page_header,
const parquet::ColumnChunk& column,
const Dictionary& dictionary) {
if (page_header.data_page_header.encoding != parquet::Encoding::RLE_DICTIONARY) {
return arrow::Status::NotImplemented("Only support RLE_DICTIONARY encoding data page");
}
if (page_header.compressed_page_size != page_header.uncompressed_page_size) {
return arrow::Status::NotImplemented("Only support uncompressed data page");
}
const auto unified_column_name = get_unified_column_name(column);
const auto num_values = page_header.data_page_header.num_values;
ARROW_ASSIGN_OR_RAISE(const auto buffer, _file->ReadAt(offset, page_header.uncompressed_page_size));
const uint8_t* raw_buffer = buffer->data();
uint64_t repetition_length;
std::vector<uint32_t> repetition_levels;
if (_schema[unified_column_name]->max_repetition_level != 0) {
ARROW_RETURN_NOT_OK(
parse_repetition_levels(raw_buffer, page_header, column, &repetition_length, &repetition_levels));
} else {
repetition_length = 0;
repetition_levels.resize(num_values, 0);
}
uint64_t definition_length;
std::vector<uint32_t> definition_levels;
if (_schema[unified_column_name]->max_definition_level != 0) {
ARROW_RETURN_NOT_OK(parse_definition_levels(raw_buffer + repetition_length, page_header, column,
&definition_length, &definition_levels));
} else {
definition_length = 0;
definition_levels.resize(num_values, 1);
}
const auto* element = _schema[unified_column_name].get();
const auto max_definition_level = element->max_definition_level;
const uint8_t bit_width = *(raw_buffer + repetition_length + definition_length);
const uint64_t remain_length = page_header.uncompressed_page_size - repetition_length - definition_length - 1;
if (remain_length == 0) {
return std::make_shared<ColumnData>(std::move(repetition_levels), std::move(definition_levels),
std::vector<std::string>{});
}
arrow::util::RleDecoder value_decoder(
raw_buffer + repetition_length + definition_length + 1,
page_header.uncompressed_page_size - repetition_length - definition_length - 1, bit_width);
std::vector<uint32_t> idxs(num_values);
value_decoder.GetBatch(idxs.data(), num_values);
auto get_value = [this, &column, &dictionary](const uint32_t idx) -> std::string {
if (column.meta_data.type == parquet::Type::INT64) {
return std::to_string(*reinterpret_cast<const int64_t*>(dictionary.get(idx)));
} else if (column.meta_data.type == parquet::Type::DOUBLE) {
return std::to_string(*reinterpret_cast<const double*>(dictionary.get(idx)));
} else if (column.meta_data.type == parquet::Type::BYTE_ARRAY) {
const uint32_t length = *reinterpret_cast<const uint32_t*>(dictionary.get(idx));
return std::string(reinterpret_cast<const char*>(dictionary.get(idx)) + sizeof(uint32_t), length);
} else {
return std::string("unsupported type");
}
};
std::vector<std::string> values;
auto it = idxs.begin();
if (definition_length == 0) {
while (it != idxs.end()) {
const auto idx = *it++;
const auto value = get_value(idx);
print(value);
values.push_back(std::move(value));
}
} else {
for (const auto definition_level : definition_levels) {
if (definition_level < max_definition_level) {
const auto value = "NULL";
print(value);
values.push_back(std::move(value));
} else {
const auto idx = *it++;
const auto value = get_value(idx);
print(value);
values.push_back(std::move(value));
}
}
}
return std::make_shared<ColumnData>(std::move(repetition_levels), std::move(definition_levels),
std::move(values));
}
arrow::Status parse_repetition_levels(const uint8_t* buffer, const parquet::PageHeader& page_header,
const parquet::ColumnChunk& column, uint64_t* length,
std::vector<std::uint32_t>* repetition_levels) {
const auto unified_column_name = get_unified_column_name(column);
const auto max_repetition_level = _schema[unified_column_name]->max_repetition_level;
if (max_repetition_level == 0) {
*length = 0;
return arrow::Status::OK();
}
const int32_t bit_width = std::ceil(std::log2(max_repetition_level + 1));
const auto num_values = page_header.data_page_header.num_values;
const uint32_t repetition_level_length = *reinterpret_cast<const uint32_t*>(buffer);
*length = sizeof(uint32_t) + repetition_level_length;
arrow::util::RleDecoder repetition_level_decoder(buffer + sizeof(uint32_t), repetition_level_length, bit_width);
repetition_levels->resize(num_values);
int values_read = repetition_level_decoder.GetBatch(repetition_levels->data(), num_values);
ASSERT_TRUE(values_read == num_values);
print("repetition_levels: ", vector_to_string(*repetition_levels));
return arrow::Status::OK();
}
arrow::Status parse_definition_levels(const uint8_t* buffer, const parquet::PageHeader& page_header,
const parquet::ColumnChunk& column, uint64_t* length,
std::vector<std::uint32_t>* definition_levels) {
const auto unified_column_name = get_unified_column_name(column);
const auto max_definition_level = _schema[unified_column_name]->max_definition_level;
if (max_definition_level == 0) {
*length = 0;
return arrow::Status::OK();
}
const int32_t bit_width = std::ceil(std::log2(max_definition_level + 1));
const auto num_values = page_header.data_page_header.num_values;
const uint32_t definition_level_length = *reinterpret_cast<const uint32_t*>(buffer);
*length = sizeof(uint32_t) + definition_level_length;
arrow::util::RleDecoder definition_decoder(buffer + sizeof(uint32_t), definition_level_length, bit_width);
definition_levels->resize(num_values);
int values_read = definition_decoder.GetBatch(definition_levels->data(), num_values);
ASSERT_TRUE(values_read == num_values);
print("definition_levels: ", vector_to_string(*definition_levels));
return arrow::Status::OK();
}
arrow::Status pretty_print_row_group() {
print("Structured Data: ");
increase_indent();
ARROW_ASSIGN_OR_RAISE(auto root, StructuredData::build(_leafs));
for (size_t repetition_idx = 0; repetition_idx < root->repetition_num(); ++repetition_idx) {
print("Row: ", repetition_idx);
increase_indent();
const auto& nested_fields = root->get_repetition(repetition_idx);
ASSERT_TRUE(nested_fields.size() == 1);
const auto& it = nested_fields.find("schema");
ASSERT_TRUE(it != nested_fields.end());
std::stringstream buffer;
ARROW_RETURN_NOT_OK(it->second->to_pretty_string(buffer, ""));
std::string line;
while (std::getline(buffer, line)) {
print(line);
}
decrease_indent();
}
decrease_indent();
return arrow::Status::OK();
}
TreeElement* left_deep_child(TreeElement* root) {
TreeElement* cur = root;
while (!cur->children.empty()) {
cur = cur->children.front();
}
return cur;
}
std::string get_unified_column_name(const parquet::ColumnChunk& column) {
return "schema." + vector_to_string(column.meta_data.path_in_schema, false, ".");
}
template <typename Item>
std::string vector_to_string(const std::vector<Item>& items, const bool boundary = true,
const std::string delimiter = ", ") {
std::stringstream buffer;
for (const auto& item : items) {
buffer << item << delimiter;
}
std::string str = buffer.str();
if (!items.empty()) {
str.resize(str.size() - delimiter.size());
}
if (boundary) {
return "[" + str + "]";
} else {
return str;
}
}
void increase_indent() { _indent += " "; }
void decrease_indent() {
if (!_indent.empty()) _indent.resize(_indent.size() - 4);
}
void reset_indent() { _indent.resize(0); }
template <typename... Args>
void print(Args&&... args) {
std::cout << _indent;
(std::cout << ... << args);
std::cout << std::endl;
}
std::shared_ptr<arrow::io::ReadableFile> _file;
uint64_t _file_size;
parquet::FileMetaData _file_metadata;
std::shared_ptr<TreeElement> _root;
std::unordered_map<std::string, std::shared_ptr<TreeElement>> _schema;
std::vector<TreeElement*> _leafs;
std::string _indent;
};
int main() {
try {
ParquetNativeReader reader("data.parquet");
auto status = reader.parse();
if (!status.ok()) {
std::cout << status.message() << std::endl;
}
} catch (...) {
std::cout << boost::stacktrace::stacktrace() << std::endl;
}
return 0;
}
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