Files
scylladb/types/collection.hh
2019-01-24 09:56:38 +01:00

133 lines
6.3 KiB
C++

/*
* Copyright (C) 2014 ScyllaDB
*/
/*
* This file is part of Scylla.
*
* Scylla is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Scylla is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <seastar/core/shared_ptr.hh>
#include <seastar/core/sstring.hh>
#include <vector>
#include "types.hh"
class collection_type_impl : public abstract_type {
static logging::logger _logger;
static thread_local std::unordered_map<data_type, shared_ptr<cql3::cql3_type>> _cql3_type_cache; // initialized on demand
public:
static constexpr size_t max_elements = 65535;
class kind {
std::function<shared_ptr<cql3::column_specification> (shared_ptr<cql3::column_specification> collection, bool is_key)> _impl;
public:
kind(std::function<shared_ptr<cql3::column_specification> (shared_ptr<cql3::column_specification> collection, bool is_key)> impl)
: _impl(std::move(impl)) {}
shared_ptr<cql3::column_specification> make_collection_receiver(shared_ptr<cql3::column_specification> collection, bool is_key) const;
static const kind map;
static const kind set;
static const kind list;
};
const kind& _kind;
protected:
explicit collection_type_impl(sstring name, const kind& k)
: abstract_type(std::move(name), {}, data::type_info::make_collection()), _kind(k) {}
virtual sstring cql3_type_name() const = 0;
public:
// representation of a collection mutation, key/value pairs, value is a mutation itself
struct mutation {
tombstone tomb;
std::vector<std::pair<bytes, atomic_cell>> cells;
// Expires cells based on query_time. Expires tombstones based on max_purgeable and gc_before.
// Removes cells covered by tomb or this->tomb.
bool compact_and_expire(row_tombstone tomb, gc_clock::time_point query_time,
can_gc_fn&, gc_clock::time_point gc_before);
};
struct mutation_view {
tombstone tomb;
std::vector<std::pair<bytes_view, atomic_cell_view>> cells;
mutation materialize(const collection_type_impl&) const;
};
virtual data_type name_comparator() const = 0;
virtual data_type value_comparator() const = 0;
shared_ptr<cql3::column_specification> make_collection_receiver(shared_ptr<cql3::column_specification> collection, bool is_key) const;
virtual bool is_collection() const override { return true; }
bool is_map() const { return &_kind == &kind::map; }
bool is_set() const { return &_kind == &kind::set; }
bool is_list() const { return &_kind == &kind::list; }
std::vector<atomic_cell> enforce_limit(std::vector<atomic_cell>, int version) const;
virtual std::vector<bytes> serialized_values(std::vector<atomic_cell> cells) const = 0;
bytes serialize_for_native_protocol(std::vector<atomic_cell> cells, int version) const;
virtual bool is_compatible_with(const abstract_type& previous) const override;
virtual bool is_value_compatible_with_internal(const abstract_type& other) const override;
virtual bool is_compatible_with_frozen(const collection_type_impl& previous) const = 0;
virtual bool is_value_compatible_with_frozen(const collection_type_impl& previous) const = 0;
virtual shared_ptr<cql3::cql3_type> as_cql3_type() const override;
template <typename BytesViewIterator>
static bytes pack(BytesViewIterator start, BytesViewIterator finish, int elements, cql_serialization_format sf);
// requires linearized collection_mutation_view, lifetime
mutation_view deserialize_mutation_form(bytes_view in) const;
bool is_empty(collection_mutation_view in) const;
bool is_any_live(collection_mutation_view in, tombstone tomb = tombstone(), gc_clock::time_point now = gc_clock::time_point::min()) const;
api::timestamp_type last_update(collection_mutation_view in) const;
virtual bytes to_value(mutation_view mut, cql_serialization_format sf) const = 0;
bytes to_value(collection_mutation_view mut, cql_serialization_format sf) const;
// FIXME: use iterators?
collection_mutation serialize_mutation_form(const mutation& mut) const;
collection_mutation serialize_mutation_form(mutation_view mut) const;
collection_mutation serialize_mutation_form_only_live(mutation_view mut, gc_clock::time_point now) const;
collection_mutation merge(collection_mutation_view a, collection_mutation_view b) const;
collection_mutation difference(collection_mutation_view a, collection_mutation_view b) const;
// Calls Func(atomic_cell_view) for each cell in this collection.
// noexcept if Func doesn't throw.
template<typename Func>
void for_each_cell(collection_mutation_view c, Func&& func) const {
c.data.with_linearized([&] (bytes_view c_bv) {
auto m_view = deserialize_mutation_form(c_bv);
for (auto&& c : m_view.cells) {
func(std::move(c.second));
}
});
}
virtual void serialize(const void* value, bytes::iterator& out, cql_serialization_format sf) const = 0;
virtual data_value deserialize(bytes_view v, cql_serialization_format sf) const = 0;
data_value deserialize_value(bytes_view v, cql_serialization_format sf) const {
return deserialize(v, sf);
}
bytes_opt reserialize(cql_serialization_format from, cql_serialization_format to, bytes_view_opt v) const;
};
template <typename BytesViewIterator>
bytes
collection_type_impl::pack(BytesViewIterator start, BytesViewIterator finish, int elements, cql_serialization_format sf) {
size_t len = collection_size_len(sf);
size_t psz = collection_value_len(sf);
for (auto j = start; j != finish; j++) {
len += j->size() + psz;
}
bytes out(bytes::initialized_later(), len);
bytes::iterator i = out.begin();
write_collection_size(i, elements, sf);
while (start != finish) {
write_collection_value(i, sf, *start++);
}
return out;
}