wgtmac commented on code in PR #624: URL: https://github.com/apache/iceberg-cpp/pull/624#discussion_r3309200970
########## src/iceberg/puffin/puffin_writer.cc: ########## @@ -0,0 +1,176 @@ +/* + * 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. + */ + +#include "iceberg/puffin/puffin_writer.h" + +#include <array> + +#include "iceberg/file_io.h" +#include "iceberg/puffin/json_serde_internal.h" +#include "iceberg/puffin/puffin_format.h" +#include "iceberg/util/endian.h" +#include "iceberg/util/macros.h" + +namespace iceberg::puffin { + +PuffinWriter::PuffinWriter(std::unique_ptr<PositionOutputStream> stream, + std::unordered_map<std::string, std::string> properties, + PuffinCompressionCodec default_codec, bool compress_footer) + : stream_(std::move(stream)), + properties_(std::move(properties)), + default_codec_(default_codec), + compress_footer_(compress_footer) {} + +PuffinWriter::~PuffinWriter() = default; + +Result<std::unique_ptr<PuffinWriter>> PuffinWriter::Make( + std::unique_ptr<OutputFile> output_file, + std::unordered_map<std::string, std::string> properties, + PuffinCompressionCodec default_codec, bool compress_footer) { + if (!output_file) { + return InvalidArgument("output_file must not be null"); + } + ICEBERG_ASSIGN_OR_RAISE(auto stream, output_file->CreateOrOverwrite()); + return std::unique_ptr<PuffinWriter>(new PuffinWriter( + std::move(stream), std::move(properties), default_codec, compress_footer)); +} + +Status PuffinWriter::WriteBytes(std::span<const std::byte> data) { + return stream_->Write(data); +} + +Status PuffinWriter::WriteMagic() { + const auto& magic = PuffinFormat::kMagicV1; + return WriteBytes(std::span<const std::byte>( + reinterpret_cast<const std::byte*>(magic.data()), magic.size())); +} + +Status PuffinWriter::WriteHeader() { + if (header_written_) return {}; + ICEBERG_RETURN_UNEXPECTED(WriteMagic()); + header_written_ = true; + return {}; +} + +Result<BlobMetadata> PuffinWriter::Write(const Blob& blob) { + if (finished_) { + return Invalid("Writer already finished"); + } + + ICEBERG_RETURN_UNEXPECTED(WriteHeader()); + + auto codec = blob.requested_compression.value_or(default_codec_); + std::span<const std::byte> input_span( + reinterpret_cast<const std::byte*>(blob.data.data()), blob.data.size()); + ICEBERG_ASSIGN_OR_RAISE(auto compressed, Compress(codec, input_span)); + + ICEBERG_ASSIGN_OR_RAISE(auto offset, stream_->Position()); + ICEBERG_RETURN_UNEXPECTED( + WriteBytes(std::span<const std::byte>(compressed.data(), compressed.size()))); + auto length = static_cast<int64_t>(compressed.size()); + + auto codec_name = CodecName(codec); + BlobMetadata metadata{ + .type = blob.type, + .input_fields = blob.input_fields, + .snapshot_id = blob.snapshot_id, + .sequence_number = blob.sequence_number, + .offset = offset, + .length = length, + .compression_codec = std::string(codec_name), + .properties = blob.properties, + }; + written_blobs_metadata_.push_back(metadata); + return metadata; +} + +Status PuffinWriter::Finish() { + if (finished_) { + return Invalid("Writer already finished"); + } + + ICEBERG_RETURN_UNEXPECTED(WriteHeader()); + + FileMetadata file_metadata{ + .blobs = written_blobs_metadata_, + .properties = properties_, + }; + + auto footer_json = ToJsonString(file_metadata); + std::vector<std::byte> footer_payload( + reinterpret_cast<const std::byte*>(footer_json.data()), + reinterpret_cast<const std::byte*>(footer_json.data() + footer_json.size())); + + // Compress footer if requested + std::array<uint8_t, 4> flags{}; + if (compress_footer_) { + ICEBERG_ASSIGN_OR_RAISE( + footer_payload, + Compress(PuffinFormat::kDefaultFooterCompressionCodec, footer_payload)); + SetFlag(flags, PuffinFlag::kFooterPayloadCompressed); + } + + // Footer start magic + ICEBERG_ASSIGN_OR_RAISE(auto footer_start, stream_->Position()); + ICEBERG_RETURN_UNEXPECTED(WriteMagic()); + + // Footer payload + ICEBERG_RETURN_UNEXPECTED(WriteBytes(footer_payload)); + + // Footer struct: payload_size (4) + flags (4) + magic (4) + auto payload_size = static_cast<int32_t>(footer_payload.size()); + std::array<std::byte, 4> size_buf{}; + WriteLittleEndian(payload_size, size_buf.data()); + ICEBERG_RETURN_UNEXPECTED(WriteBytes(size_buf)); + + // Flags + ICEBERG_RETURN_UNEXPECTED(WriteBytes(std::span<const std::byte>( + reinterpret_cast<const std::byte*>(flags.data()), flags.size()))); + + // Footer end magic + ICEBERG_RETURN_UNEXPECTED(WriteMagic()); + + ICEBERG_ASSIGN_OR_RAISE(auto end_pos, stream_->Position()); Review Comment: Finish records file_size/footer_size and sets finished_ before Flush/Close returns. Java only marks the writer finished and records storedLength after close, because some streams emit final bytes on close. If Close fails or finalizes extra bytes, this writer reports a finished state and wrong size. ########## src/iceberg/puffin/puffin_writer.h: ########## @@ -0,0 +1,106 @@ +/* + * 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. + */ + +#pragma once + +/// \file iceberg/puffin/puffin_writer.h +/// Puffin file writer. + +#include <cstddef> +#include <cstdint> +#include <memory> +#include <span> +#include <string> +#include <unordered_map> +#include <vector> + +#include "iceberg/iceberg_data_export.h" +#include "iceberg/puffin/file_metadata.h" +#include "iceberg/result.h" + +namespace iceberg { +class OutputFile; +class PositionOutputStream; +} // namespace iceberg + +namespace iceberg::puffin { + +/// \brief Writer for Puffin files. +/// +/// Writes blobs and footer to an OutputFile stream. +class ICEBERG_DATA_EXPORT PuffinWriter { + public: + /// \brief Create a PuffinWriter for the given output file. + /// \param output_file The output file to write to. + /// \param properties File-level properties to include in the footer. + /// \param default_codec Default compression codec for blobs. + /// \param compress_footer Whether to compress the footer payload. + static Result<std::unique_ptr<PuffinWriter>> Make( + std::unique_ptr<OutputFile> output_file, + std::unordered_map<std::string, std::string> properties = {}, + PuffinCompressionCodec default_codec = PuffinCompressionCodec::kNone, + bool compress_footer = false); + + ~PuffinWriter(); Review Comment: Java PuffinWriter implements close(), and close() implicitly finishes an unfinished file. This API exposes only Finish() and the destructor is a no-op, so ported code has no Java-equivalent close path and can leave an invalid Puffin file if Finish() is not called explicitly. -- 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. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
