// Copyright 2023 PingCAP, Inc.
//
// Licensed 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 <DataStreams/IBlockInputStream.h>


namespace DB
{

/** Empty stream of blocks of specified structure.
  */
class NullBlockInputStream : public IBlockInputStream
{
public:
    explicit NullBlockInputStream(const Block & header)
        : header(header)
    {}

    Block read() override { return {}; }
    Block getHeader() const override { return header; }
    String getName() const override { return "Null"; }

private:
    Block header;
};

} // namespace DB