memgraph/src/storage/indexes/index.hpp

#pragma once

#include <memory>

#include "data_structures/concurrent/concurrent_map.hpp"
#include "storage/indexes/index_record.hpp"
#include "storage/indexes/index_record_collection.hpp"
#include "storage/label/label.hpp"

template <class Key, class Item>
class Index
{
public:
    using container_t = ConcurrentMap<Key, Item>;

    Index() : index(std::make_unique<container_t>()) {}

    auto update(const Label &label, VertexIndexRecord &&index_record)
    {
        auto accessor = index->access();
        auto label_ref = label_ref_t(label);

        // create Index Record Collection if it doesn't exist
        if (!accessor.contains(label_ref)) {
            accessor.insert_unique(label_ref,
                                   std::move(VertexIndexRecordCollection()));
        }

        // add Vertex Index Record to the Record Collection
        auto &record_collection = (*accessor.find(label_ref)).second;
        record_collection.add(std::forward<VertexIndexRecord>(index_record));
    }

    VertexIndexRecordCollection& find(const Label& label)
    {
        // TODO: accessor should be outside?
        // bacause otherwise GC could delete record that has just be returned
        auto label_ref = label_ref_t(label);
        auto accessor = index->access();
        return (*accessor.find(label_ref)).second;
    }

private:
    std::unique_ptr<container_t> index;
};