cpp-ch/local-engine/Storages/SubstraitSource/ParquetFormatFile.h

/*
 * 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 "config.h"

#if USE_PARQUET
#include <Storages/Parquet/ParquetMeta.h>
#include <Storages/SubstraitSource/FormatFile.h>

namespace local_engine
{

class ParquetFormatFile : public FormatFile
{
public:
    explicit ParquetFormatFile(
        const DB::ContextPtr & context_,
        const substrait::ReadRel::LocalFiles::FileOrFiles & file_info_,
        const ReadBufferBuilderPtr & read_buffer_builder_,
        bool use_local_format_);
    ~ParquetFormatFile() override = default;

    InputFormatPtr
    createInputFormat(const DB::Block & header, const std::shared_ptr<const DB::ActionsDAG> & filter_actions_dag = nullptr) override;

    std::optional<size_t> getTotalRows() override;

    bool supportSplit() const override { return true; }

    String getFileFormat() const override { return "Parquet"; }

    static bool onlyHasFlatType(const DB::Block & header);

    void initialize(const ColumnIndexFilterPtr &) override;

private:
    bool use_pageindex_reader;
    std::mutex mutex;
    std::optional<size_t> total_rows;

    /// We need the file schema when reading iceberg parquet, and hence we need the read buffer when ParquetFormatFile is
    /// created. To avoid opening the file twice, We have to keep read_buffer_ alive until createInputFormat is called.
    /// After that, the read_buffer_ will be moved to the InputFormat
    std::unique_ptr<DB::ReadBuffer> read_buffer_;

    /// TODO: we should use KeyCondition instead of ColumnIndexFilter, this is a temporary solution
    /// initialized at initialize() to avoid defining special createInputFormat, and reset once createInputFormat is called.
    ColumnIndexFilterPtr column_index_filter_;
};

}
#endif