mirror of
https://github.com/matrix-construct/construct
synced 2024-08-23 10:04:47 +02:00
133 lines
4 KiB
C++
133 lines
4 KiB
C++
// Matrix Construct
|
|
//
|
|
// Copyright (C) Matrix Construct Developers, Authors & Contributors
|
|
// Copyright (C) 2016-2018 Jason Volk <jason@zemos.net>
|
|
//
|
|
// Permission to use, copy, modify, and/or distribute this software for any
|
|
// purpose with or without fee is hereby granted, provided that the above
|
|
// copyright notice and this permission notice is present in all copies. The
|
|
// full license for this software is available in the LICENSE file.
|
|
|
|
#pragma once
|
|
#define HAVE_IRCD_DB_ROW_H
|
|
|
|
namespace ircd::db
|
|
{
|
|
struct row;
|
|
|
|
// [SET] Delete row from DB (convenience to an op::DELETE delta)
|
|
void del(row &, const sopts & = {});
|
|
}
|
|
|
|
/// A `row` is a collection of cells from different columns which all share the same
|
|
/// key. This is an interface for dealing with those cells in the aggregate.
|
|
///
|
|
/// Note that in a `row` each `cell` comes from a different `column`, but `cell::key()`
|
|
/// will all return the same index value across the whole `row`. To get the names
|
|
/// of the columns themselves to build ex. the key name of a JSON key-value pair,
|
|
/// use `cell::col()`, which will be different for each `cell` across the `row`.
|
|
///
|
|
/// The db::row::iterator iterates over the cells in a row; to iterate over
|
|
/// multiple rows use the db::cursor
|
|
struct ircd::db::row
|
|
:vector_view<cell>
|
|
{
|
|
struct delta;
|
|
|
|
public:
|
|
bool valid() const; // true on any cell valid; false on empty
|
|
bool valid(const string_view &) const; // true on any cell valid equal; false on empty
|
|
|
|
// [GET] Find cell by name
|
|
const_iterator find(const string_view &column) const;
|
|
iterator find(const string_view &column);
|
|
|
|
// [GET] Get cell (or throw)
|
|
const cell &operator[](const size_t &column) const;
|
|
const cell &operator[](const string_view &column) const;
|
|
cell &operator[](const size_t &column);
|
|
cell &operator[](const string_view &column);
|
|
|
|
// [SET] Perform operation
|
|
void operator()(const op &, const string_view &col, const string_view &val = {}, const sopts & = {});
|
|
|
|
using vector_view<cell>::vector_view;
|
|
|
|
row(database &,
|
|
const string_view &key = {},
|
|
const vector_view<string_view> &columns = {},
|
|
const vector_view<cell> &buf = {},
|
|
gopts opts = {});
|
|
|
|
template<class... T>
|
|
row(database &,
|
|
const string_view &key = {},
|
|
const json::tuple<T...> & = {},
|
|
const vector_view<cell> &buf = {},
|
|
gopts opts = {});
|
|
|
|
template<class pos> friend size_t seek(row &, const pos &);
|
|
};
|
|
|
|
namespace ircd::db
|
|
{
|
|
// [SET] Perform operations in a sequence as a single transaction. No template
|
|
// iterators supported yet, just a ptr range good for contiguous sequences.
|
|
void write(const row::delta *const &begin, const row::delta *const &end, const sopts & = {});
|
|
void write(const std::initializer_list<row::delta> &, const sopts & = {});
|
|
void write(const sopts &, const std::initializer_list<row::delta> &);
|
|
void write(const row::delta &, const sopts & = {});
|
|
}
|
|
|
|
//
|
|
// A delta is an element of a database transaction. You can use this to make
|
|
// an all-succeed-or-all-fail commitment to multiple rows at once. It is also
|
|
// useful to make a commitment on a single row as a convenient way to compose
|
|
// all of a row's cells together.
|
|
//
|
|
struct ircd::db::row::delta
|
|
:std::tuple<op, row *>
|
|
{
|
|
enum
|
|
{
|
|
OP, ROW
|
|
};
|
|
|
|
delta(row &r, const enum op &op = op::SET)
|
|
:std::tuple<enum op, row *>{op, &r}
|
|
{}
|
|
|
|
delta(const enum op &op, row &r)
|
|
:std::tuple<enum op, row *>{op, &r}
|
|
{}
|
|
};
|
|
|
|
template<class... T>
|
|
ircd::db::row::row(database &d,
|
|
const string_view &key,
|
|
const json::tuple<T...> &t,
|
|
const vector_view<cell> &buf,
|
|
gopts opts)
|
|
:row{[&d, &key, &t, &buf, &opts]
|
|
() -> row
|
|
{
|
|
std::array<string_view, t.size()> cols;
|
|
json::_key_transform(t, std::begin(cols), std::end(cols));
|
|
return { d, key, cols, buf, opts };
|
|
}()}
|
|
{
|
|
}
|
|
|
|
inline ircd::db::cell &
|
|
ircd::db::row::operator[](const size_t &i)
|
|
{
|
|
return vector_view<cell>::at(i);
|
|
}
|
|
|
|
inline const ircd::db::cell &
|
|
ircd::db::row::operator[](const size_t &i)
|
|
const
|
|
{
|
|
return vector_view<cell>::at(i);
|
|
}
|