arrow_schema.hpp

Go to the documentation of this file.

// Copyright 2024 Man Group Operations Limited
//
// 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 <array>
#include <concepts>
#include <cstdint>
#include <memory>
#include <optional>
#include <ranges>
#include <unordered_set>
 
#include "sparrow/utils/repeat_container.hpp"
 
 
#if defined(__cpp_lib_format)
#    include <format>
#    include <ostream>
#endif
 
#include "sparrow/arrow_interface/arrow_schema/private_data.hpp"
#include "sparrow/c_interface.hpp"
#include "sparrow/config/config.hpp"
#include "sparrow/utils/contracts.hpp"
#include "sparrow/utils/metadata.hpp"
 
namespace sparrow
{
    template <class F, class N, input_metadata_container M = std::vector<metadata_pair>, std::ranges::input_range CHILDREN_OWNERSHIP>
        requires std::constructible_from<arrow_schema_private_data::FormatType, F>
                 && std::constructible_from<arrow_schema_private_data::NameType, N>
                 && std::is_same_v<std::ranges::range_value_t<CHILDREN_OWNERSHIP>, bool>
    [[nodiscard]] ArrowSchema make_arrow_schema(
        F format,
        N name,
        std::optional<M> metadata,
        std::optional<std::unordered_set<ArrowFlag>> flags,
        ArrowSchema** children,
        const CHILDREN_OWNERSHIP& children_ownership,
        ArrowSchema* dictionary,
        bool dictionary_ownership
    );

    SPARROW_API void release_arrow_schema(ArrowSchema* schema);

    SPARROW_API void empty_release_arrow_schema(ArrowSchema* schema);
 
    template <class F, class N, input_metadata_container M = std::vector<metadata_pair>, std::ranges::input_range CHILDREN_OWNERSHIP>
        requires std::constructible_from<arrow_schema_private_data::FormatType, F>
                 && std::constructible_from<arrow_schema_private_data::NameType, N>
                 && std::is_same_v<std::ranges::range_value_t<CHILDREN_OWNERSHIP>, bool>
    void fill_arrow_schema(
        ArrowSchema& schema,
        F format,
        N name,
        std::optional<M> metadata,
        std::optional<std::unordered_set<ArrowFlag>> flags,
        ArrowSchema** children,
        const CHILDREN_OWNERSHIP& children_ownership,
        ArrowSchema* dictionary,
        bool dictionary_ownership
    )
    {
        SPARROW_ASSERT_TRUE(children_ownership.size() >= 0);
        SPARROW_ASSERT_TRUE(children_ownership.size() > 0 ? children != nullptr : children == nullptr);
        SPARROW_ASSERT_FALSE(format.empty());
        if (children)
        {
            for (size_t i = 0; i < children_ownership.size(); ++i)
            {
                SPARROW_ASSERT_FALSE(children[i] == nullptr);
            }
        }
 
        schema.flags = 0;
        if (flags.has_value())
        {
            for (const auto& flag : *flags)
            {
                schema.flags |= static_cast<int64_t>(flag);
            }
        }
        schema.n_children = static_cast<int64_t>(children_ownership.size());
 
        std::optional<std::string> metadata_str = metadata.has_value()
                                                      ? std::make_optional(
                                                            get_metadata_from_key_values(*metadata)
                                                        )
                                                      : std::nullopt;
 
        schema.private_data = new arrow_schema_private_data(
            std::move(format),
            std::move(name),
            std::move(metadata_str),
            children_ownership,
            dictionary_ownership
        );
 
        const auto private_data = static_cast<arrow_schema_private_data*>(schema.private_data);
        schema.format = private_data->format_ptr();
        schema.name = private_data->name_ptr();
        schema.metadata = private_data->metadata_ptr();
        schema.children = children;
        schema.dictionary = dictionary;
        schema.release = release_arrow_schema;
    }
 
    template <class F, class N, input_metadata_container M, std::ranges::input_range CHILDREN_OWNERSHIP>
        requires std::constructible_from<arrow_schema_private_data::FormatType, F>
                 && std::constructible_from<arrow_schema_private_data::NameType, N>
                 && std::is_same_v<std::ranges::range_value_t<CHILDREN_OWNERSHIP>, bool>
    [[nodiscard]] ArrowSchema make_arrow_schema(
        F format,
        N name,
        std::optional<M> metadata,
        std::optional<std::unordered_set<ArrowFlag>> flags,
        ArrowSchema** children,
        const CHILDREN_OWNERSHIP& children_ownership,
        ArrowSchema* dictionary,
        bool dictionary_ownership
    )
    {
        SPARROW_ASSERT_TRUE(children_ownership.size() >= 0);
        SPARROW_ASSERT_TRUE(children_ownership.size() > 0 ? children != nullptr : children == nullptr);
        SPARROW_ASSERT_FALSE(format.empty());
        if (children)
        {
            for (size_t i = 0; i < children_ownership.size(); ++i)
            {
                SPARROW_ASSERT_FALSE(children[i] == nullptr);
            }
        }
 
        ArrowSchema schema{};
        fill_arrow_schema(
            schema,
            std::move(format),
            std::move(name),
            std::move(metadata),
            flags,
            children,
            children_ownership,
            dictionary,
            dictionary_ownership
        );
        return schema;
    };
 
    inline ArrowSchema make_empty_arrow_schema()
    {
        using namespace std::literals;
        return make_arrow_schema<std::string_view, std::string_view, std::vector<metadata_pair>>(
            "n"sv,
            ""sv,
            std::nullopt,
            std::nullopt,
            nullptr,
            std::array<bool, 0>{},
            nullptr,
            false
        );
    }

    SPARROW_API void swap(ArrowSchema& lhs, ArrowSchema& rhs) noexcept;

    SPARROW_API void copy_schema(const ArrowSchema& source, ArrowSchema& target);

    [[nodiscard]]
    inline ArrowSchema copy_schema(const ArrowSchema& source)
    {
        ArrowSchema target{};
        copy_schema(source, target);
        return target;
    }

    inline ArrowSchema move_schema(ArrowSchema&& source)
    {
        ArrowSchema target = make_empty_arrow_schema();
        swap(source, target);
        source.release(&source);
        return target;
    }

    inline ArrowSchema move_schema(ArrowSchema& source)
    {
        return move_schema(std::move(source));
    }
}
 
#if defined(__cpp_lib_format)
 
template <>
struct std::formatter<ArrowSchema>
{
    constexpr auto parse(std::format_parse_context& ctx)
    {
        return ctx.begin();  // Simple implementation
    }
 
    auto format(const ArrowSchema& obj, std::format_context& ctx) const
    {
        std::string children_str = std::format("{}", static_cast<void*>(obj.children));
        for (int i = 0; i < obj.n_children; ++i)
        {
            children_str += std::format("\n-{}", static_cast<void*>(obj.children[i]));
        }
 
        const std::string format = obj.format ? obj.format : "nullptr";
        const std::string name = obj.name ? obj.name : "nullptr";
        const std::string metadata = obj.metadata ? obj.metadata : "nullptr";
 
        return std::format_to(
            ctx.out(),
            "ArrowSchema - ptr address: {}\n- format: {}\n- name: {}\n- metadata: {}\n- flags: {}\n- n_children: {}\n- children: {}\n- dictionary: {}\n- release: {}\n- private_data: {}\n",
            static_cast<const void*>(&obj),
            format,
            name,
            metadata,
            obj.flags,
            obj.n_children,
            children_str,
            static_cast<const void*>(obj.dictionary),
            static_cast<const void*>(std::addressof(obj.release)),
            obj.private_data
        );
    }
};
 
inline std::ostream& operator<<(std::ostream& os, const ArrowSchema& value)
{
    os << std::format("{}", value);
    return os;
}
 
#endif