path: root/simulation/governance.go

// Copyright 2018 The dexon-consensus-core Authors
// This file is part of the dexon-consensus-core library.
//
// The dexon-consensus-core library is free software: you can redistribute it
// and/or modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation, either version 3 of the License,
// or (at your option) any later version.
//
// The dexon-consensus-core library 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 Lesser
// General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the dexon-consensus-core library. If not, see
// <http://www.gnu.org/licenses/>.

package simulation

import (
    "fmt"
    "sync"
    "time"

    "github.com/dexon-foundation/dexon-consensus-core/core/crypto"
    "github.com/dexon-foundation/dexon-consensus-core/core/types"
    "github.com/dexon-foundation/dexon-consensus-core/simulation/config"
)

// simGovernance is a simulated governance contract implementing the
// core.Governance interface.
type simGovernance struct {
    id                 types.NodeID
    lock               sync.RWMutex
    notarySet          map[types.NodeID]struct{}
    expectedNumNodes   int
    k                  int
    phiRatio           float32
    chainNum           uint32
    crs                []byte
    tsig               map[uint64]crypto.Signature
    dkgComplaint       map[uint64][]*types.DKGComplaint
    dkgMasterPublicKey map[uint64][]*types.DKGMasterPublicKey
    lambdaBA           time.Duration
    lambdaDKG          time.Duration
    network            *network
}

// newSimGovernance returns a new simGovernance instance.
func newSimGovernance(
    id types.NodeID,
    numNodes int, consensusConfig config.Consensus) *simGovernance {
    return &simGovernance{
        id:                 id,
        notarySet:          make(map[types.NodeID]struct{}),
        expectedNumNodes:   numNodes,
        k:                  consensusConfig.K,
        phiRatio:           consensusConfig.PhiRatio,
        chainNum:           consensusConfig.ChainNum,
        crs:                []byte(consensusConfig.GenesisCRS),
        tsig:               make(map[uint64]crypto.Signature),
        dkgComplaint:       make(map[uint64][]*types.DKGComplaint),
        dkgMasterPublicKey: make(map[uint64][]*types.DKGMasterPublicKey),
        lambdaBA:           time.Duration(consensusConfig.LambdaBA) * time.Millisecond,
        lambdaDKG:          time.Duration(consensusConfig.LambdaDKG) * time.Millisecond,
    }
}

func (g *simGovernance) setNetwork(network *network) {
    g.network = network
}

// GetNotarySet returns the current notary set.
func (g *simGovernance) GetNotarySet(
    blockHeight uint64) map[types.NodeID]struct{} {
    g.lock.RLock()
    defer g.lock.RUnlock()

    // Return the cloned notarySet.
    ret := make(map[types.NodeID]struct{})
    for k := range g.notarySet {
        ret[k] = struct{}{}
    }
    return ret
}

// GetConfiguration returns the configuration at a given block height.
func (g *simGovernance) GetConfiguration(blockHeight uint64) *types.Config {
    return &types.Config{
        NumShards: 1,
        NumChains: g.chainNum,
        CRS:       g.crs,
        LambdaBA:  g.lambdaBA,
        LambdaDKG: g.lambdaDKG,
        K:         g.k,
        PhiRatio:  g.phiRatio,
    }
}

// addNode add a new node into the simulated governance contract.
func (g *simGovernance) addNode(nID types.NodeID) {
    g.lock.Lock()
    defer g.lock.Unlock()

    if _, exists := g.notarySet[nID]; exists {
        return
    }
    if len(g.notarySet) == g.expectedNumNodes {
        panic(fmt.Errorf("attempt to add node when ready"))
    }
    g.notarySet[nID] = struct{}{}
}

// ProposeThresholdSignature porposes a ThresholdSignature of round.
func (g *simGovernance) ProposeThresholdSignature(
    round uint64, signature crypto.Signature) {
    g.tsig[round] = signature
}

// GetThresholdSignature gets a ThresholdSignature of round.
func (g *simGovernance) GetThresholdSignature(round uint64) (
    sig crypto.Signature, exist bool) {
    sig, exist = g.tsig[round]
    return
}

// AddDKGComplaint adds a DKGComplaint.
func (g *simGovernance) AddDKGComplaint(complaint *types.DKGComplaint) {
    // TODO(jimmy-dexon): check if the input is valid.
    g.dkgComplaint[complaint.Round] = append(
        g.dkgComplaint[complaint.Round], complaint)
    if complaint.ProposerID == g.id {
        g.network.broadcast(complaint)
    }
}

// DKGComplaints returns the DKGComplaints of round.
func (g *simGovernance) DKGComplaints(round uint64) []*types.DKGComplaint {
    complaints, exist := g.dkgComplaint[round]
    if !exist {
        return []*types.DKGComplaint{}
    }
    return complaints
}

// AddDKGMasterPublicKey adds a DKGMasterPublicKey.
func (g *simGovernance) AddDKGMasterPublicKey(
    masterPublicKey *types.DKGMasterPublicKey) {
    // TODO(jimmy-dexon): check if the input is valid.
    g.dkgMasterPublicKey[masterPublicKey.Round] = append(
        g.dkgMasterPublicKey[masterPublicKey.Round], masterPublicKey)
    if masterPublicKey.ProposerID == g.id {
        g.network.broadcast(masterPublicKey)
    }
}

// DKGMasterPublicKeys returns the DKGMasterPublicKeys of round.
func (g *simGovernance) DKGMasterPublicKeys(
    round uint64) []*types.DKGMasterPublicKey {
    masterPublicKeys, exist := g.dkgMasterPublicKey[round]
    if !exist {
        return []*types.DKGMasterPublicKey{}
    }
    return masterPublicKeys
}