PeerGroup.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_TEST_CSF_PEERGROUP_H_INCLUDED
#define RIPPLE_TEST_CSF_PEERGROUP_H_INCLUDED
 
#include <algorithm>
#include <test/csf/Peer.h>
#include <test/csf/random.h>
#include <vector>
 
namespace ripple {
namespace test {
namespace csf {
 
class PeerGroup
{
    using peers_type = std::vector<Peer*>;
    peers_type peers_;
 
public:
    using iterator = peers_type::iterator;
    using const_iterator = peers_type::const_iterator;
    using reference = peers_type::reference;
    using const_reference = peers_type::const_reference;
 
    PeerGroup() = default;
    PeerGroup(Peer* peer) : peers_{1, peer}
    {
    }
    PeerGroup(std::vector<Peer*>&& peers) : peers_{std::move(peers)}
    {
        std::sort(peers_.begin(), peers_.end());
    }
    PeerGroup(std::vector<Peer*> const& peers) : peers_{peers}
    {
        std::sort(peers_.begin(), peers_.end());
    }
 
    PeerGroup(std::set<Peer*> const& peers) : peers_{peers.begin(), peers.end()}
    {
    }
 
    iterator
    begin()
    {
        return peers_.begin();
    }
 
    iterator
    end()
    {
        return peers_.end();
    }
 
    const_iterator
    begin() const
    {
        return peers_.begin();
    }
 
    const_iterator
    end() const
    {
        return peers_.end();
    }
 
    const_reference
    operator[](std::size_t i) const
    {
        return peers_[i];
    }
 
    bool
    contains(Peer const* p)
    {
        return std::find(peers_.begin(), peers_.end(), p) != peers_.end();
    }
 
    bool
    contains(PeerID id)
    {
        return std::find_if(peers_.begin(), peers_.end(), [id](Peer const* p) {
                   return p->id == id;
               }) != peers_.end();
    }
 
    std::size_t
    size() const
    {
        return peers_.size();
    }
 
    void
    trust(PeerGroup const& o)
    {
        for (Peer* p : peers_)
        {
            for (Peer* target : o.peers_)
            {
                p->trust(*target);
            }
        }
    }
 
    void
    untrust(PeerGroup const& o)
    {
        for (Peer* p : peers_)
        {
            for (Peer* target : o.peers_)
            {
                p->untrust(*target);
            }
        }
    }
 
    void
    connect(PeerGroup const& o, SimDuration delay)
    {
        for (Peer* p : peers_)
        {
            for (Peer* target : o.peers_)
            {
                // cannot send messages to self over network
                if (p != target)
                    p->connect(*target, delay);
            }
        }
    }
 
    void
    disconnect(PeerGroup const& o)
    {
        for (Peer* p : peers_)
        {
            for (Peer* target : o.peers_)
            {
                p->disconnect(*target);
            }
        }
    }
 
    void
    trustAndConnect(PeerGroup const& o, SimDuration delay)
    {
        trust(o);
        connect(o, delay);
    }
 
    void
    connectFromTrust(SimDuration delay)
    {
        for (Peer* peer : peers_)
        {
            for (Peer* to : peer->trustGraph.trustedPeers(peer))
            {
                peer->connect(*to, delay);
            }
        }
    }
 
    // Union of PeerGroups
    friend PeerGroup
    operator+(PeerGroup const& a, PeerGroup const& b)
    {
        PeerGroup res;
        std::set_union(
            a.peers_.begin(),
            a.peers_.end(),
            b.peers_.begin(),
            b.peers_.end(),
            std::back_inserter(res.peers_));
        return res;
    }
 
    // Set difference of PeerGroups
    friend PeerGroup
    operator-(PeerGroup const& a, PeerGroup const& b)
    {
        PeerGroup res;
 
        std::set_difference(
            a.peers_.begin(),
            a.peers_.end(),
            b.peers_.begin(),
            b.peers_.end(),
            std::back_inserter(res.peers_));
 
        return res;
    }
 
    friend std::ostream&
    operator<<(std::ostream& o, PeerGroup const& t)
    {
        o << "{";
        bool first = true;
        for (Peer const* p : t)
        {
            if (!first)
                o << ", ";
            first = false;
            o << p->id;
        }
        o << "}";
        return o;
    }
};
 
template <class RandomNumberDistribution, class Generator>
std::vector<PeerGroup>
randomRankedGroups(
    PeerGroup& peers,
    std::vector<double> const& ranks,
    int numGroups,
    RandomNumberDistribution sizeDist,
    Generator& g)
{
    assert(peers.size() == ranks.size());
 
    std::vector<PeerGroup> groups;
    groups.reserve(numGroups);
    std::vector<Peer*> rawPeers(peers.begin(), peers.end());
    std::generate_n(std::back_inserter(groups), numGroups, [&]() {
        std::vector<Peer*> res = random_weighted_shuffle(rawPeers, ranks, g);
        res.resize(sizeDist(g));
        return PeerGroup(std::move(res));
    });
 
    return groups;
}
 
template <class RandomNumberDistribution, class Generator>
void
randomRankedTrust(
    PeerGroup& peers,
    std::vector<double> const& ranks,
    int numGroups,
    RandomNumberDistribution sizeDist,
    Generator& g)
{
    std::vector<PeerGroup> const groups =
        randomRankedGroups(peers, ranks, numGroups, sizeDist, g);
 
    std::uniform_int_distribution<int> u(0, groups.size() - 1);
    for (auto& peer : peers)
    {
        for (auto& target : groups[u(g)])
            peer->trust(*target);
    }
}
 
template <class RandomNumberDistribution, class Generator>
void
randomRankedConnect(
    PeerGroup& peers,
    std::vector<double> const& ranks,
    int numGroups,
    RandomNumberDistribution sizeDist,
    Generator& g,
    SimDuration delay)
{
    std::vector<PeerGroup> const groups =
        randomRankedGroups(peers, ranks, numGroups, sizeDist, g);
 
    std::uniform_int_distribution<int> u(0, groups.size() - 1);
    for (auto& peer : peers)
    {
        for (auto& target : groups[u(g)])
            peer->connect(*target, delay);
    }
}
 
}  // namespace csf
}  // namespace test
}  // namespace ripple
#endif