feat: add file_io and local fs impl

Signed-off-by: Junwang Zhao <zhjwpku@gmail.com>

Author: zhjwpku

src/iceberg/CMakeLists.txt

@@ -15,7 +15,7 @@
 # specific language governing permissions and limitations
 # under the License.
 
-set(ICEBERG_SOURCES demo_table.cc)
+set(ICEBERG_SOURCES demo_table.cc io/fs_file_io.cc)
 
 add_iceberg_lib(iceberg
                 SOURCES

src/iceberg/io/file_io.h

@@ -0,0 +1,77 @@
+/*
+ * 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 <string>
+
+#include "iceberg/iceberg_export.h"
+
+namespace iceberg {
+namespace io {
+
+class ICEBERG_EXPORT InputFile {
+ public:
+  explicit InputFile(std::string path) : path_(std::move(path)) {}
+
+  virtual ~InputFile() = default;
+
+  virtual bool exists() const = 0;
+
+  const std::string& path() const { return path_; }
+
+ protected:
+  std::string path_;
+};
+
+class ICEBERG_EXPORT OutputFile {
+ public:
+  explicit OutputFile(std::string path) : path_(std::move(path)) {}
+
+  virtual ~OutputFile() = default;
+
+  virtual void create() = 0;
+
+  const std::string& path() const { return path_; }
+
+ protected:
+  std::string path_;
+};
+
+class ICEBERG_EXPORT FileIO {
+ public:
+  explicit FileIO(std::string name) : name_(std::move(name)) {}
+
+  virtual ~FileIO() = default;
+
+  virtual std::shared_ptr<InputFile> newInputFile(const std::string& path) = 0;
+  virtual std::shared_ptr<OutputFile> newOutputFile(const std::string& path) = 0;
+
+  virtual void DeleteFile(const std::string& path) = 0;
+  void DeleteFile(const InputFile& ifile) { return DeleteFile(ifile.path()); }
+  void DeleteFile(const OutputFile& ofile) { return DeleteFile(ofile.path()); }
+
+  const std::string& name() const { return name_; }
+
+ protected:
+  std::string name_;
+};
+
+}  // namespace io
+}  // namespace iceberg

src/iceberg/io/fs_file_io.cc

@@ -0,0 +1,54 @@
+/*
+ * 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 "fs_file_io.h"
+
+#include <fcntl.h>
+
+#include <cassert>
+#include <filesystem>
+
+namespace iceberg {
+namespace io {
+
+bool FsInputFile::exists() const { return std::filesystem::exists(path()); }
+
+void FsOutputFile::create() {
+  int fd = open(path().c_str(), O_CREAT | O_WRONLY, 0666);
+  assert(fd != -1);
+  // TODO: how to handle this scenario
+}
+
+std::shared_ptr<InputFile> FsFileIO::newInputFile(const std::string& path) {
+  return std::make_shared<FsInputFile>(path);
+}
+
+std::shared_ptr<OutputFile> FsFileIO::newOutputFile(const std::string& path) {
+  return std::make_shared<FsOutputFile>(path);
+}
+
+void FsFileIO::DeleteFile(const std::string& path) {
+  std::error_code ec;
+  bool ret = std::filesystem::remove(path, ec);
+  assert(ret);
+  // TODO: how to handle this scenario
+}
+
+}  // namespace io
+}  // namespace iceberg

src/iceberg/io/fs_file_io.h

@@ -0,0 +1,55 @@
+/*
+ * 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 "file_io.h"
+
+namespace iceberg {
+namespace io {
+
+class ICEBERG_EXPORT FsInputFile : public InputFile {
+ public:
+  explicit FsInputFile(std::string path) : InputFile(std::move(path)) {}
+  ~FsInputFile() = default;
+
+  bool exists() const override;
+};
+
+class ICEBERG_EXPORT FsOutputFile : public OutputFile {
+ public:
+  explicit FsOutputFile(std::string path) : OutputFile(std::move(path)) {}
+  ~FsOutputFile() = default;
+
+  void create() override;
+};
+
+class ICEBERG_EXPORT FsFileIO : public FileIO {
+ public:
+  FsFileIO() : FileIO("fs") {}
+  ~FsFileIO() = default;
+
+  std::shared_ptr<InputFile> newInputFile(const std::string& path) override;
+  std::shared_ptr<OutputFile> newOutputFile(const std::string& path) override;
+
+  void DeleteFile(const std::string& path) override;
+};
+
+}  // namespace io
+}  // namespace iceberg

test/core/CMakeLists.txt

@@ -16,7 +16,7 @@
 # under the License.
 
 add_executable(core_unittest)
-target_sources(core_unittest PRIVATE core_unittest.cc)
+target_sources(core_unittest PRIVATE core_unittest.cc file_io_test.cc)
 target_link_libraries(core_unittest PRIVATE iceberg_static GTest::gtest_main)
 target_include_directories(core_unittest PRIVATE "${ICEBERG_INCLUDES}")
 add_test(NAME core_unittest COMMAND core_unittest)

test/core/file_io_test.cc

@@ -0,0 +1,53 @@
+/*
+ * 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 <filesystem>
+
+#include <gtest/gtest.h>
+
+#include "iceberg/io/fs_file_io.h"
+
+namespace iceberg {
+
+namespace io {
+
+class FsFileIOTest : public testing::Test {
+ protected:
+  void SetUp() override { fs = std::make_shared<FsFileIO>(); }
+
+  std::shared_ptr<FileIO> fs;
+  std::filesystem::path tmpfile = std::filesystem::temp_directory_path() / "123.txt";
+};
+
+TEST_F(FsFileIOTest, newOutputFile) {
+  auto out = fs->newOutputFile(tmpfile);
+  out->create();
+  ASSERT_EQ(out->path(), tmpfile.string());
+}
+
+TEST_F(FsFileIOTest, newInputFile) {
+  auto in = fs->newInputFile(tmpfile);
+  ASSERT_TRUE(in->exists());
+  ASSERT_EQ(in->path(), tmpfile.string());
+  fs->DeleteFile(in->path());
+}
+
+}  // namespace io
+
+}  // namespace iceberg