// 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 test
import (
"encoding/hex"
"reflect"
"sort"
"sync"
"time"
"github.com/dexon-foundation/dexon-consensus-core/common"
"github.com/dexon-foundation/dexon-consensus-core/core/crypto"
"github.com/dexon-foundation/dexon-consensus-core/core/crypto/ecdsa"
"github.com/dexon-foundation/dexon-consensus-core/core/types"
typesDKG "github.com/dexon-foundation/dexon-consensus-core/core/types/dkg"
)
// Governance is an implementation of Goverance for testing purpose.
type Governance struct {
configs []*types.Config
nodeSets [][]crypto.PublicKey
state *State
lock sync.RWMutex
}
// NewGovernance constructs a Governance instance.
func NewGovernance(genesisNodes []crypto.PublicKey,
lambda time.Duration) (g *Governance, err error) {
// Setup a State instance.
// TODO(mission): it's not a good idea to embed initialization of one
// public class in another, I did this to make the range of
// modification smaller.
g = &Governance{
state: NewState(genesisNodes, lambda, true),
}
return
}
// NodeSet implements Governance interface to return current
// notary set.
func (g *Governance) NodeSet(round uint64) []crypto.PublicKey {
if round == 0 || round == 1 {
// Round 0, 1 are genesis round, their configs should be created
// by default.
g.CatchUpWithRound(round)
}
g.lock.RLock()
defer g.lock.RUnlock()
if round >= uint64(len(g.nodeSets)) {
return nil
}
return g.nodeSets[round]
}
// Configuration returns the configuration at a given block height.
func (g *Governance) Configuration(round uint64) *types.Config {
if round == 0 || round == 1 {
// Round 0, 1 are genesis round, their configs should be created
// by default.
g.CatchUpWithRound(round)
}
g.lock.RLock()
defer g.lock.RUnlock()
if round >= uint64(len(g.nodeSets)) {
return nil
}
return g.configs[round]
}
// CRS returns the CRS for a given round.
func (g *Governance) CRS(round uint64) common.Hash {
return g.state.CRS(round)
}
// NotifyRoundHeight notifies governace contract to snapshot config.
func (g *Governance) NotifyRoundHeight(round, height uint64) {
g.CatchUpWithRound(round)
}
// ProposeCRS propose a CRS.
func (g *Governance) ProposeCRS(round uint64, signedCRS []byte) {
g.lock.Lock()
defer g.lock.Unlock()
crs := crypto.Keccak256Hash(signedCRS)
if err := g.state.ProposeCRS(round, crs); err != nil {
// CRS can be proposed multiple times, other errors are not
// accepted.
if err != ErrDuplicatedChange {
panic(err)
}
}
}
// AddDKGComplaint add a DKGComplaint.
func (g *Governance) AddDKGComplaint(
round uint64, complaint *typesDKG.Complaint) {
if round != complaint.Round {
return
}
if g.IsDKGFinal(complaint.Round) {
return
}
g.state.RequestChange(StateAddDKGComplaint, complaint)
}
// DKGComplaints returns the DKGComplaints of round.
func (g *Governance) DKGComplaints(round uint64) []*typesDKG.Complaint {
return g.state.DKGComplaints(round)
}
// AddDKGMasterPublicKey adds a DKGMasterPublicKey.
func (g *Governance) AddDKGMasterPublicKey(
round uint64, masterPublicKey *typesDKG.MasterPublicKey) {
if round != masterPublicKey.Round {
return
}
g.state.RequestChange(StateAddDKGMasterPublicKey, masterPublicKey)
}
// DKGMasterPublicKeys returns the DKGMasterPublicKeys of round.
func (g *Governance) DKGMasterPublicKeys(
round uint64) []*typesDKG.MasterPublicKey {
return g.state.DKGMasterPublicKeys(round)
}
// AddDKGFinalize adds a DKG finalize message.
func (g *Governance) AddDKGFinalize(round uint64, final *typesDKG.Finalize) {
if round != final.Round {
return
}
g.state.RequestChange(StateAddDKGFinal, final)
}
// IsDKGFinal checks if DKG is final.
func (g *Governance) IsDKGFinal(round uint64) bool {
if round == 0 || round == 1 {
// Round 0, 1 are genesis round, their configs should be created
// by default.
g.CatchUpWithRound(round)
}
g.lock.RLock()
defer g.lock.RUnlock()
if round >= uint64(len(g.configs)) {
return false
}
return g.state.IsDKGFinal(round, int(g.configs[round].DKGSetSize)/3*2)
}
//
// Test Utilities
//
// State allows to access embed State instance.
func (g *Governance) State() *State {
return g.state
}
// CatchUpWithRound attempts to perform state snapshot to
// provide configuration/nodeSet for round R.
func (g *Governance) CatchUpWithRound(round uint64) {
if func() bool {
g.lock.RLock()
defer g.lock.RUnlock()
return uint64(len(g.configs)) > round
}() {
return
}
g.lock.Lock()
defer g.lock.Unlock()
for uint64(len(g.configs)) <= round {
config, nodeSet := g.state.Snapshot()
g.configs = append(g.configs, config)
g.nodeSets = append(g.nodeSets, nodeSet)
}
}
// Clone a governance instance with replicate internal state.
func (g *Governance) Clone() *Governance {
g.lock.RLock()
defer g.lock.RUnlock()
// Clone state.
copiedState := g.state.Clone()
// Clone configs.
copiedConfigs := []*types.Config{}
for _, c := range g.configs {
copiedConfigs = append(copiedConfigs, c.Clone())
}
// Clone node sets.
// NOTE: here I assume the key is from ecdsa.
copiedNodeSets := [][]crypto.PublicKey{}
for _, nodeSetForRound := range g.nodeSets {
copiedNodeSet := []crypto.PublicKey{}
for _, node := range nodeSetForRound {
pubKey, err := ecdsa.NewPublicKeyFromByteSlice(node.Bytes())
if err != nil {
panic(err)
}
copiedNodeSet = append(copiedNodeSet, pubKey)
}
copiedNodeSets = append(copiedNodeSets, copiedNodeSet)
}
return &Governance{
configs: copiedConfigs,
state: copiedState,
nodeSets: copiedNodeSets,
}
}
// Equal checks equality between two Governance instances.
func (g *Governance) Equal(other *Governance, checkState bool) bool {
// Check configs.
if !reflect.DeepEqual(g.configs, other.configs) {
return false
}
// Check node sets.
if len(g.nodeSets) != len(other.nodeSets) {
return false
}
getSortedKeys := func(keys []crypto.PublicKey) (encoded []string) {
for _, key := range keys {
encoded = append(encoded, hex.EncodeToString(key.Bytes()))
}
sort.Strings(encoded)
return
}
for round, nodeSetsForRound := range g.nodeSets {
otherNodeSetsForRound := other.nodeSets[round]
if len(nodeSetsForRound) != len(otherNodeSetsForRound) {
return false
}
if !reflect.DeepEqual(
getSortedKeys(nodeSetsForRound),
getSortedKeys(otherNodeSetsForRound)) {
return false
}
}
// Check state if needed.
//
// While testing, it's expected that two governance instances contain
// different state, only the snapshots (configs and node sets) are
// essentially equal.
if checkState {
return g.state.Equal(other.state) == nil
}
return true
}
