DatabaseShard.h

//------------------------------------------------------------------------------
/*
    This file is part of rippled: https://github.com/ripple/rippled
    Copyright (c) 2012, 2017 Ripple Labs Inc.
 
    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 appear in all copies.
 
    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================
 
#ifndef RIPPLE_NODESTORE_DATABASESHARD_H_INCLUDED
#define RIPPLE_NODESTORE_DATABASESHARD_H_INCLUDED
 
#include <ripple/app/ledger/Ledger.h>
#include <ripple/basics/RangeSet.h>
#include <ripple/nodestore/Database.h>
#include <ripple/nodestore/Types.h>
 
#include <boost/optional.hpp>
 
#include <memory>
 
namespace ripple {
namespace NodeStore {
 
class DatabaseShard : public Database
{
public:
    DatabaseShard(
        std::string const& name,
        Stoppable& parent,
        Scheduler& scheduler,
        int readThreads,
        Section const& config,
        beast::Journal journal)
        : Database(name, parent, scheduler, readThreads, config, journal)
    {
    }
 
    virtual bool
    init() = 0;
 
    virtual boost::optional<std::uint32_t>
    prepareLedger(std::uint32_t validLedgerSeq) = 0;
 
    virtual bool
    prepareShards(std::vector<std::uint32_t> const& shardIndexes) = 0;
 
    virtual void
    removePreShard(std::uint32_t shardIndex) = 0;
 
    virtual std::string
    getPreShards() = 0;
 
    virtual bool
    importShard(
        std::uint32_t shardIndex,
        boost::filesystem::path const& srcDir) = 0;
 
    virtual std::shared_ptr<Ledger>
    fetchLedger(uint256 const& hash, std::uint32_t seq) = 0;
 
    virtual void
    setStored(std::shared_ptr<Ledger const> const& ledger) = 0;
 
    virtual std::string
    getCompleteShards() = 0;
 
    virtual std::uint32_t
    ledgersPerShard() const = 0;
 
    virtual std::uint32_t
    earliestShardIndex() const = 0;
 
    virtual std::uint32_t
    seqToShardIndex(std::uint32_t seq) const = 0;
 
    virtual std::uint32_t
    firstLedgerSeq(std::uint32_t shardIndex) const = 0;
 
    virtual std::uint32_t
    lastLedgerSeq(std::uint32_t shardIndex) const = 0;
 
    virtual boost::filesystem::path const&
    getRootDir() const = 0;
 
    static constexpr std::uint32_t ledgersPerShardDefault{16384u};
};
 
constexpr std::uint32_t
seqToShardIndex(
    std::uint32_t ledgerSeq,
    std::uint32_t ledgersPerShard = DatabaseShard::ledgersPerShardDefault)
{
    return (ledgerSeq - 1) / ledgersPerShard;
}
 
extern std::unique_ptr<DatabaseShard>
make_ShardStore(
    Application& app,
    Stoppable& parent,
    Scheduler& scheduler,
    int readThreads,
    beast::Journal j);
 
}  // namespace NodeStore
}  // namespace ripple
 
#endif