change_stream.hpp

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// Copyright 2009-present MongoDB, 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 <mongocxx/change_stream-fwd.hpp> // IWYU pragma: export
 
//
 
#include <mongocxx/v1/change_stream.hpp> // IWYU pragma: export
 
#include <cstdint>
#include <iterator>
#include <memory> // IWYU pragma: keep: backward compatibility, to be removed.
#include <type_traits>
#include <utility>
 
#include <mongocxx/client-fwd.hpp>     // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/collection-fwd.hpp> // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/database-fwd.hpp>   // IWYU pragma: keep: backward compatibility, to be removed.
 
#include <bsoncxx/document/view.hpp>
#include <bsoncxx/stdx/optional.hpp>
 
#include <mongocxx/config/prelude.hpp>
 
namespace mongocxx {
namespace v_noabi {

class change_stream {
   private:
    v1::change_stream _stream;
    bsoncxx::v_noabi::document::view _doc;
 
   public:
    class iterator;

    MONGOCXX_ABI_EXPORT_CDECL() change_stream(change_stream&& other) noexcept;

    MONGOCXX_ABI_EXPORT_CDECL(change_stream&) operator=(change_stream&& other) noexcept;

    change_stream(change_stream const& other) = delete;

    change_stream& operator=(change_stream const& other) = delete;

    MONGOCXX_ABI_EXPORT_CDECL() ~change_stream();

    /* explicit(false) */ change_stream(v1::change_stream stream) : _stream{std::move(stream)} {}

    explicit operator v1::change_stream() && {
        return std::move(_stream);
    }

    explicit operator v1::change_stream() const& = delete;

    MONGOCXX_ABI_EXPORT_CDECL(iterator) begin() const;

    MONGOCXX_ABI_EXPORT_CDECL(iterator) end() const;

    bsoncxx::v1::stdx::optional<bsoncxx::v_noabi::document::view> get_resume_token() const {
        return _stream.get_resume_token();
    }
};

class change_stream::iterator {
   public:
    // Support input-iterator (caveat of post-increment returning void)
    using difference_type = std::int64_t;
    using value_type = bsoncxx::v_noabi::document::view const;
    using pointer = std::add_pointer<value_type>::type;
    using reference = std::add_lvalue_reference<value_type>::type;
    using iterator_category = std::input_iterator_tag;

    MONGOCXX_ABI_EXPORT_CDECL() iterator();

    MONGOCXX_ABI_EXPORT_CDECL(bsoncxx::v_noabi::document::view const&) operator*() const;

    MONGOCXX_ABI_EXPORT_CDECL(bsoncxx::v_noabi::document::view const*) operator->() const;

    MONGOCXX_ABI_EXPORT_CDECL(iterator&) operator++();

    void operator++(int) {
        this->operator++();
    }

    friend MONGOCXX_ABI_EXPORT_CDECL(bool) operator==(
        change_stream::iterator const& lhs,
        change_stream::iterator const& rhs) noexcept;
 
    friend bool operator!=(change_stream::iterator const& lhs, change_stream::iterator const& rhs) noexcept {
        return !(lhs == rhs);
    }

 
   private:
    friend change_stream;
 
    explicit iterator(change_stream* change_stream, bool is_end);
 
    bool is_exhausted() const;
 
    change_stream* _change_stream;
    bool _is_end;
};

inline v_noabi::change_stream from_v1(v1::change_stream v) {
    return {std::move(v)};
}

inline v1::change_stream to_v1(v_noabi::change_stream v) {
    return v1::change_stream{std::move(v)};
}
 
} // namespace v_noabi
} // namespace mongocxx
 
#include <mongocxx/config/postlude.hpp>