feat: support decompress gzip metadata

src/iceberg/CMakeLists.txt

@@ -42,17 +42,24 @@ set(ICEBERG_SOURCES
     type.cc
     util/murmurhash3_internal.cc
     util/timepoint.cc
-    util/unreachable.cc)
+    util/unreachable.cc
+    util/gzip_internal.cc)
 
 set(ICEBERG_STATIC_BUILD_INTERFACE_LIBS)
 set(ICEBERG_SHARED_BUILD_INTERFACE_LIBS)
 set(ICEBERG_STATIC_INSTALL_INTERFACE_LIBS)
 set(ICEBERG_SHARED_INSTALL_INTERFACE_LIBS)
 
-list(APPEND ICEBERG_STATIC_BUILD_INTERFACE_LIBS nanoarrow::nanoarrow
-     nlohmann_json::nlohmann_json)
-list(APPEND ICEBERG_SHARED_BUILD_INTERFACE_LIBS nanoarrow::nanoarrow
-     nlohmann_json::nlohmann_json)
+list(APPEND
+     ICEBERG_STATIC_BUILD_INTERFACE_LIBS
+     nanoarrow::nanoarrow
+     nlohmann_json::nlohmann_json
+     ZLIB::ZLIB)
+list(APPEND
+     ICEBERG_SHARED_BUILD_INTERFACE_LIBS
+     nanoarrow::nanoarrow
+     nlohmann_json::nlohmann_json
+     ZLIB::ZLIB)
 list(APPEND ICEBERG_STATIC_INSTALL_INTERFACE_LIBS "Iceberg::nanoarrow"
      "Iceberg::nlohmann_json")
 list(APPEND ICEBERG_SHARED_INSTALL_INTERFACE_LIBS "Iceberg::nanoarrow"

src/iceberg/result.h

@@ -38,6 +38,7 @@ enum class ErrorKind {
   kJsonParseError,
   kNoSuchNamespace,
   kNoSuchTable,
+  kDecompressError,
   kNotFound,
   kNotImplemented,
   kNotSupported,
@@ -80,6 +81,7 @@ DEFINE_ERROR_FUNCTION(IOError)
 DEFINE_ERROR_FUNCTION(JsonParseError)
 DEFINE_ERROR_FUNCTION(NoSuchNamespace)
 DEFINE_ERROR_FUNCTION(NoSuchTable)
+DEFINE_ERROR_FUNCTION(DecompressError)
 DEFINE_ERROR_FUNCTION(NotFound)
 DEFINE_ERROR_FUNCTION(NotImplemented)
 DEFINE_ERROR_FUNCTION(NotSupported)

src/iceberg/table_metadata.cc

@@ -20,7 +20,6 @@
 #include "iceberg/table_metadata.h"
 
 #include <format>
-#include <ranges>
 #include <string>
 
 #include <nlohmann/json.hpp>
@@ -32,6 +31,7 @@
 #include "iceberg/schema.h"
 #include "iceberg/snapshot.h"
 #include "iceberg/sort_order.h"
+#include "iceberg/util/gzip_internal.h"
 #include "iceberg/util/macros.h"
 
 namespace iceberg {
@@ -156,11 +156,16 @@ Result<MetadataFileCodecType> TableMetadataUtil::CodecFromFileName(
 Result<std::unique_ptr<TableMetadata>> TableMetadataUtil::Read(
     FileIO& io, const std::string& location, std::optional<size_t> length) {
   ICEBERG_ASSIGN_OR_RAISE(auto codec_type, CodecFromFileName(location));
+
+  ICEBERG_ASSIGN_OR_RAISE(auto content, io.ReadFile(location, length));
   if (codec_type == MetadataFileCodecType::kGzip) {
-    return NotImplemented("Reading gzip-compressed metadata files is not supported yet");
+    auto gzip_decompressor = std::make_unique<GZipDecompressor>();
+    ICEBERG_RETURN_UNEXPECTED(gzip_decompressor->Init());
+    auto result = gzip_decompressor->Decompress(content);
+    ICEBERG_RETURN_UNEXPECTED(result);
+    content = result.value();
   }
 
-  ICEBERG_ASSIGN_OR_RAISE(auto content, io.ReadFile(location, length));
   ICEBERG_ASSIGN_OR_RAISE(auto json, FromJsonString(content));
   return TableMetadataFromJson(json);
 }

src/iceberg/util/gzip_internal.cc

@@ -0,0 +1,94 @@
+/*
+ * 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/util/gzip_internal.h"
+
+#include <zlib.h>
+
+#include <cstring>
+
+#include "iceberg/util/macros.h"
+
+namespace iceberg {
+
+class ZlibImpl {
+ public:
+  ZlibImpl() { memset(&stream_, 0, sizeof(stream_)); }
+
+  ~ZlibImpl() {
+    if (initialized_) {
+      inflateEnd(&stream_);
+    }
+  }
+
+  Status Init() {
+    // Maximum window size
+    static int kWindowBits = 15;
+    // Determine if this is libz or gzip from header.
+    static int kDetectCodec = 32;
+    int ret = inflateInit2(&stream_, kWindowBits | kDetectCodec);
+    if (ret != Z_OK) {
+      return DecompressError("inflateInit2 failed, result:{}", ret);
+    }
+    initialized_ = true;
+    return {};
+  }
+
+  Result<std::string> Decompress(const std::string& compressed_data) {
+    if (compressed_data.empty()) {
+      return {};
+    }
+    if (!initialized_) {
+      ICEBERG_RETURN_UNEXPECTED(Init());
+    }
+    stream_.avail_in = static_cast<uInt>(compressed_data.size());
+    stream_.next_in = reinterpret_cast<Bytef*>(const_cast<char*>(compressed_data.data()));
+
+    // TODO(xiao.dong) magic buffer, can we get a estimated size from compressed data?
+    std::vector<char> out_buffer(32 * 1024);
+    std::string result;
+    int ret = 0;
+    do {
+      stream_.avail_out = static_cast<uInt>(out_buffer.size());
+      stream_.next_out = reinterpret_cast<Bytef*>(out_buffer.data());
+      ret = inflate(&stream_, Z_NO_FLUSH);
+      if (ret != Z_OK && ret != Z_STREAM_END) {
+        return DecompressError("inflate failed, result:{}", ret);
+      }
+      result.append(out_buffer.data(), out_buffer.size() - stream_.avail_out);
+    } while (ret != Z_STREAM_END);
+    return result;
+  }
+
+ private:
+  bool initialized_ = false;
+  z_stream stream_;
+};
+
+GZipDecompressor::GZipDecompressor() : zlib_impl_(std::make_unique<ZlibImpl>()) {}
+
+GZipDecompressor::~GZipDecompressor() = default;
+
+Status GZipDecompressor::Init() { return zlib_impl_->Init(); }
+
+Result<std::string> GZipDecompressor::Decompress(const std::string& compressed_data) {
+  return zlib_impl_->Decompress(compressed_data);
+}
+
+}  // namespace iceberg

src/iceberg/util/gzip_internal.h

@@ -0,0 +1,45 @@
+/*
+ * 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
+
+#include <memory>
+#include <string>
+
+#include "iceberg/result.h"
+
+namespace iceberg {
+
+class ZlibImpl;
+
+class GZipDecompressor {
+ public:
+  GZipDecompressor();
+
+  ~GZipDecompressor();
+
+  Status Init();
+
+  Result<std::string> Decompress(const std::string& compressed_data);
+
+ private:
+  std::unique_ptr<ZlibImpl> zlib_impl_;
+};
+
+}  // namespace iceberg

test/CMakeLists.txt

@@ -72,7 +72,7 @@ if(ICEBERG_BUILD_BUNDLE)
 
   add_executable(arrow_test)
   target_sources(arrow_test PRIVATE arrow_test.cc arrow_fs_file_io_test.cc
-                                    metadata_io_test.cc)
+                                    metadata_io_test.cc gzip_decompress_test.cc)
   target_link_libraries(arrow_test PRIVATE iceberg_bundle_static GTest::gtest_main
                                            GTest::gmock)
   add_test(NAME arrow_test COMMAND arrow_test)

test/gzip_decompress_test.cc

@@ -0,0 +1,83 @@
+/*
+ * 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 <arrow/filesystem/localfs.h>
+#include <arrow/io/compressed.h>
+#include <arrow/io/file.h>
+#include <arrow/util/compression.h>
+#include <gtest/gtest.h>
+
+#include "iceberg/arrow/arrow_fs_file_io.h"
+#include "iceberg/file_io.h"
+#include "iceberg/util/gzip_internal.h"
+#include "matchers.h"
+#include "temp_file_test_base.h"
+
+namespace iceberg {
+
+class GZipTest : public TempFileTestBase {
+ protected:
+  void SetUp() override {
+    TempFileTestBase::SetUp();
+    io_ = std::make_shared<iceberg::arrow::ArrowFileSystemFileIO>(
+        std::make_shared<::arrow::fs::LocalFileSystem>());
+    temp_filepath_ = CreateNewTempFilePathWithSuffix("test.gz");
+  }
+
+  std::shared_ptr<iceberg::FileIO> io_;
+  std::string temp_filepath_;
+};
+
+TEST_F(GZipTest, GZipDecompressedString) {
+  auto test_string = GenerateRandomString(1024);
+
+#define ARROW_ASSIGN_OR_THROW(var, expr)   \
+  {                                        \
+    auto result = expr;                    \
+    ASSERT_TRUE(result.ok());              \
+    var = std::move(result.ValueUnsafe()); \
+  }
+  std::shared_ptr<::arrow::io::FileOutputStream> out_stream;
+  ARROW_ASSIGN_OR_THROW(out_stream, ::arrow::io::FileOutputStream::Open(temp_filepath_));
+
+  std::shared_ptr<::arrow::util::Codec> gzip_codec;
+  ARROW_ASSIGN_OR_THROW(gzip_codec,
+                        ::arrow::util::Codec::Create(::arrow::Compression::GZIP));
+
+  std::shared_ptr<::arrow::io::OutputStream> compressed_stream;
+  ARROW_ASSIGN_OR_THROW(compressed_stream, ::arrow::io::CompressedOutputStream::Make(
+                                               gzip_codec.get(), out_stream));
+#undef ARROW_ASSIGN_OR_THROW
+
+  ASSERT_TRUE(compressed_stream->Write(test_string).ok());
+  ASSERT_TRUE(compressed_stream->Flush().ok());
+  ASSERT_TRUE(compressed_stream->Close().ok());
+
+  auto result = io_->ReadFile(temp_filepath_, test_string.size());
+  EXPECT_THAT(result, IsOk());
+
+  auto gzip_decompressor = std::make_unique<GZipDecompressor>();
+  EXPECT_THAT(gzip_decompressor->Init(), IsOk());
+  EXPECT_THAT(result, IsOk());
+  auto read_data = gzip_decompressor->Decompress(result.value());
+  EXPECT_THAT(read_data, IsOk());
+  ASSERT_EQ(read_data.value(), test_string);
+}
+
+}  // namespace iceberg