core: update governance interface and move K into config (#40)

14 files changed, 233 insertions, 140 deletions

diff --git a/GNUmakefile b/GNUmakefile
index 96a5efa..6eceb31 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -55,17 +55,7 @@ pre-build: eth-dep
 pre-submit: eth-dep check-format lint test vet
 
 eth-dep:
-	@rm -rf vendor/github.com/ethereum/go-ethereum/crypto/secp256k1/libsecp256k1
-	@if [ ! -d .dep/libsecp256k1 ]; then \
-		git init .dep/libsecp256k1; \
-		cd .dep/libsecp256k1; \
-		git remote add origin https://github.com/ethereum/go-ethereum.git; \
-		git config core.sparsecheckout true; \
-		echo "crypto/secp256k1/libsecp256k1/*" >> .git/info/sparse-checkout; \
-		cd ../../; \
-	fi
-	@cd .dep/libsecp256k1; git pull --depth=1 origin master; cd ../../
-	@cp -r .dep/libsecp256k1/crypto/secp256k1/libsecp256k1 vendor/github.com/ethereum/go-ethereum/crypto/secp256k1
+	@bin/install_eth_dep.sh
 
 format:
 	@go fmt `go list ./... | grep -v 'vendor'`
diff --git a/bin/install_eth_dep.sh b/bin/install_eth_dep.sh
new file mode 100755
index 0000000..79ecd0e
--- /dev/null
+++ b/bin/install_eth_dep.sh
@@ -0,0 +1,20 @@
+#!/bin/bash
+
+if [ -e .dep/libsecp256k1 ]; then
+  exit 0
+fi
+
+rm -rf vendor/github.com/ethereum/go-ethereum/crypto/secp256k1/libsecp256k1
+if [ ! -d .dep/libsecp256k1 ]; then
+  git init .dep/libsecp256k1
+  cd .dep/libsecp256k1
+  git remote add origin https://github.com/ethereum/go-ethereum.git
+  git config core.sparsecheckout true
+  echo "crypto/secp256k1/libsecp256k1/*" >> .git/info/sparse-checkout
+  cd ../../
+fi
+cd .dep/libsecp256k1
+git pull --depth=1 origin master
+cd ../../
+cp -r .dep/libsecp256k1/crypto/secp256k1/libsecp256k1 \
+  vendor/github.com/ethereum/go-ethereum/crypto/secp256k1
diff --git a/core/consensus.go b/core/consensus.go
index 33f2f8b..d668c9e 100644
--- a/core/consensus.go
+++ b/core/consensus.go
@@ -42,7 +42,6 @@ func NewConsensus(
 	app Application,
 	gov Governance,
 	db blockdb.BlockDatabase) *Consensus {
-
 	validatorSet := gov.GetValidatorSet()
 
 	// Setup acking by information returned from Governace.
@@ -52,11 +51,9 @@ func NewConsensus(
 	}
 
 	// Setup sequencer by information returned from Governace.
-	// TODO(mission): the value of 'K' should be in governace.
-	// TODO(mission): the ratio of 'phi' should be in governance.
 	to := newTotalOrdering(
-		0,
-		uint64(2*(len(validatorSet)-1)/3+1),
+		uint64(gov.GetTotalOrderingK()),
+		uint64(float32(len(validatorSet)-1)*gov.GetPhiRatio()+1),
 		uint64(len(validatorSet)))
 
 	return &Consensus{
diff --git a/core/consensus_test.go b/core/consensus_test.go
index 1544818..beeb1a7 100644
--- a/core/consensus_test.go
+++ b/core/consensus_test.go
@@ -53,7 +53,7 @@ func (s *ConsensusTestSuite) prepareGenesisBlock(
 	return block
 }
 
-func (s *ConsensusTestSuite) prepareConsensus(gov *test.Gov) (
+func (s *ConsensusTestSuite) prepareConsensus(gov *test.Governance) (
 	*test.App, *Consensus) {
 
 	app := test.NewApp()
@@ -77,7 +77,7 @@ func (s *ConsensusTestSuite) TestSimpleDeliverBlock() {
 	// This test case only works for Total Ordering with K=0.
 	var (
 		minInterval = 50 * time.Millisecond
-		gov         = test.NewGov(4, 1000)
+		gov         = test.NewGovernance(4, 1000)
 		req         = s.Require()
 		validators  []types.ValidatorID
 	)
@@ -262,7 +262,7 @@ func (s *ConsensusTestSuite) TestPrepareBlock() {
 	//  - Make sure Consensus.PrepareBlock would only attempt to
 	//    ack the prepared block.
 	var (
-		gov        = test.NewGov(4, 1000)
+		gov        = test.NewGovernance(4, 1000)
 		req        = s.Require()
 		validators []types.ValidatorID
 	)
diff --git a/core/governance.go b/core/governance.go
index a7069a5..d94fad0 100644
--- a/core/governance.go
+++ b/core/governance.go
@@ -30,9 +30,15 @@ type Governance interface {
 	// Get the current validator set and it's corresponding stake.
 	GetValidatorSet() map[types.ValidatorID]decimal.Decimal
 
+	// Get K
+	GetTotalOrderingK() int
+
+	// Get PhiRatio
+	GetPhiRatio() float32
+
 	// Get block proposing interval (in milliseconds).
 	GetBlockProposingInterval() int
 
-	// Get membership events after a certain epoch.
-	GetMembershipEvents(epoch int) []types.MembershipEvent
+	// Get configuration change events after a certain epoch.
+	GetConfigurationChangeEvent(epoch int) []types.ConfigurationChangeEvent
 }
diff --git a/core/test/gov.go b/core/test/governance.go
index 7a5bdfc..a7ae1b0 100644
--- a/core/test/gov.go
+++ b/core/test/governance.go
@@ -23,22 +23,21 @@ import (
 	"github.com/shopspring/decimal"
 )
 
-// Gov is an implementation of Goverance for testing purpose.
-type Gov struct {
+// Governance is an implementation of Goverance for testing purpose.
+type Governance struct {
 	BlockProposingInterval int
 	Validators             map[types.ValidatorID]decimal.Decimal
 }
 
-// NewGov constructs a Gov instance.
-func NewGov(
-	validatorCount, proposingInterval int) (gov *Gov) {
+// NewGovernance constructs a Governance instance.
+func NewGovernance(validatorCount, proposingInterval int) (g *Governance) {
 
-	gov = &Gov{
+	g = &Governance{
 		BlockProposingInterval: proposingInterval,
 		Validators:             make(map[types.ValidatorID]decimal.Decimal),
 	}
 	for i := 0; i < validatorCount; i++ {
-		gov.Validators[types.ValidatorID{Hash: common.NewRandomHash()}] =
+		g.Validators[types.ValidatorID{Hash: common.NewRandomHash()}] =
 			decimal.NewFromFloat(0)
 	}
 	return
@@ -46,18 +45,29 @@ func NewGov(
 
 // GetValidatorSet implements Governance interface to return current
 // validator set.
-func (gov *Gov) GetValidatorSet() map[types.ValidatorID]decimal.Decimal {
-	return gov.Validators
+func (g *Governance) GetValidatorSet() map[types.ValidatorID]decimal.Decimal {
+	return g.Validators
 }
 
 // GetBlockProposingInterval implements Governance interface to return maximum
 // allowed block proposing interval in millisecond.
-func (gov *Gov) GetBlockProposingInterval() int {
-	return gov.BlockProposingInterval
+func (g *Governance) GetBlockProposingInterval() int {
+	return g.BlockProposingInterval
 }
 
-// GetMembershipEvents implements Governance interface to return membership
-// changed events.
-func (gov *Gov) GetMembershipEvents(epoch int) []types.MembershipEvent {
+// GetTotalOrderingK returns K.
+func (g *Governance) GetTotalOrderingK() int {
+	return 0
+}
+
+// GetPhiRatio returns phi ratio.
+func (g *Governance) GetPhiRatio() float32 {
+	return 0.667
+}
+
+// GetConfigurationChangeEvent Get configuration change events after a certain
+// epoch.
+func (g *Governance) GetConfigurationChangeEvent(
+	epoch int) []types.ConfigurationChangeEvent {
 	return nil
 }
diff --git a/core/types/configuration.go b/core/types/configuration.go
new file mode 100644
index 0000000..4158331
--- /dev/null
+++ b/core/types/configuration.go
@@ -0,0 +1,46 @@
+// 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 types
+
+// ConfigurationChangeEventType specifies the action of a membership event.
+type ConfigurationChangeEventType int
+
+// Event enums.
+const (
+	KChanged ConfigurationChangeEventType = iota
+	MembershipAdd
+	MembershipRemove
+)
+
+// IntegerEventPayload is a general payload for integer type value.
+type IntegerEventPayload struct {
+	Value int64
+}
+
+// MembershipEventPayload is the payload type for membership event.
+type MembershipEventPayload struct {
+	ID       ValidatorID
+	Evidence []byte
+}
+
+// ConfigurationChangeEvent specifies the event of membership changes.
+type ConfigurationChangeEvent struct {
+	Epoch   int
+	Event   ConfigurationChangeEventType
+	Payload interface{}
+}
diff --git a/core/types/membership-event.go b/core/types/membership-event.go
deleted file mode 100644
index 8d05039..0000000
--- a/core/types/membership-event.go
+++ /dev/null
@@ -1,16 +0,0 @@
-package types
-
-// MembershipActionType specifies the action of a membership event.
-type MembershipActionType int
-
-// Event enums.
-const (
-	MembershipActionAdd MembershipActionType = iota
-	MembershipActionDelete
-)
-
-// MembershipEvent specifies the event of membership changes.
-type MembershipEvent struct {
-	Epoch  int
-	Action MembershipActionType
-}
diff --git a/simulation/app.go b/simulation/app.go
index 2d09f2a..89b41a1 100644
--- a/simulation/app.go
+++ b/simulation/app.go
@@ -26,8 +26,8 @@ import (
 	"github.com/dexon-foundation/dexon-consensus-core/core/types"
 )
 
-// SimApp is an DEXON app for simulation.
-type SimApp struct {
+// simApp is an DEXON app for simulation.
+type simApp struct {
 	ValidatorID types.ValidatorID
 	Outputs     []*types.Block
 	Early       bool
@@ -40,9 +40,9 @@ type SimApp struct {
 	blockByHash       map[common.Hash]*types.Block
 }
 
-// NewSimApp returns point to a new instance of SimApp.
-func NewSimApp(id types.ValidatorID, Network PeerServerNetwork) *SimApp {
-	return &SimApp{
+// newSimApp returns point to a new instance of simApp.
+func newSimApp(id types.ValidatorID, Network PeerServerNetwork) *simApp {
+	return &simApp{
 		ValidatorID:       id,
 		Network:           Network,
 		DeliverID:         0,
@@ -52,13 +52,13 @@ func NewSimApp(id types.ValidatorID, Network PeerServerNetwork) *SimApp {
 	}
 }
 
-func (a *SimApp) addBlock(block *types.Block) {
+func (a *simApp) addBlock(block *types.Block) {
 	a.blockByHash[block.Hash] = block
 }
 
 // getAckedBlocks will return all unconfirmed blocks' hash with lower Height
 // than the block with ackHash.
-func (a *SimApp) getAckedBlocks(ackHash common.Hash) (output common.Hashes) {
+func (a *simApp) getAckedBlocks(ackHash common.Hash) (output common.Hashes) {
 	// TODO(jimmy-dexon): Why there are some acks never seen?
 	ackBlock, exist := a.blockByHash[ackHash]
 	if !exist {
@@ -83,12 +83,12 @@ func (a *SimApp) getAckedBlocks(ackHash common.Hash) (output common.Hashes) {
 
 // StronglyAcked is called when a block is strongly acked by DEXON
 // Reliabe Broadcast algorithm.
-func (a *SimApp) StronglyAcked(blockHash common.Hash) {
+func (a *simApp) StronglyAcked(blockHash common.Hash) {
 }
 
 // TotalOrderingDeliver is called when blocks are delivered by the total
 // ordering algorithm.
-func (a *SimApp) TotalOrderingDeliver(blockHashes common.Hashes, early bool) {
+func (a *simApp) TotalOrderingDeliver(blockHashes common.Hashes, early bool) {
 	now := time.Now()
 	blocks := make([]*types.Block, len(blockHashes))
 	for idx := range blockHashes {
@@ -147,7 +147,7 @@ func (a *SimApp) TotalOrderingDeliver(blockHashes common.Hashes, early bool) {
 }
 
 // DeliverBlock is called when a block in compaction chain is delivered.
-func (a *SimApp) DeliverBlock(blockHash common.Hash, timestamp time.Time) {
+func (a *simApp) DeliverBlock(blockHash common.Hash, timestamp time.Time) {
 	seenTime, exist := a.blockSeen[blockHash]
 	if !exist {
 		return
diff --git a/simulation/config/config.go b/simulation/config/config.go
index c704a8d..02c077b 100644
--- a/simulation/config/config.go
+++ b/simulation/config/config.go
@@ -34,8 +34,15 @@ const (
 	NetworkTypeTCPLocal NetworkType = "tcp-local"
 )
 
+// Consensus settings.
+type Consensus struct {
+	PhiRatio float32
+	K        int
+}
+
 // Validator config for the simulation.
 type Validator struct {
+	Consensus            Consensus
 	Num                  int
 	ProposeIntervalMean  float64
 	ProposeIntervalSigma float64
@@ -70,6 +77,10 @@ func GenerateDefault(path string) error {
 	config := Config{
 		Title: "DEXON Consensus Simulation Config",
 		Validator: Validator{
+			Consensus: Consensus{
+				PhiRatio: 0.66667,
+				K:        2,
+			},
 			Num:                  7,
 			ProposeIntervalMean:  500,
 			ProposeIntervalSigma: 30,
@@ -100,7 +111,7 @@ func Read(path string) (*Config, error) {
 
 	var config Config
 
-	if toml.NewDecoder(f).Decode(&config); err != nil {
+	if err := toml.NewDecoder(f).Decode(&config); err != nil {
 		return nil, err
 	}
 	return &config, nil
diff --git a/simulation/gov.go b/simulation/gov.go
deleted file mode 100644
index ddba949..0000000
--- a/simulation/gov.go
+++ /dev/null
@@ -1,74 +0,0 @@
-// 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"
-
-	"github.com/dexon-foundation/dexon-consensus-core/core/types"
-	"github.com/shopspring/decimal"
-)
-
-type simGov struct {
-	lock                  sync.RWMutex
-	validatorSet          map[types.ValidatorID]decimal.Decimal
-	expectedNumValidators int
-}
-
-func newSimGov(numValidators int) *simGov {
-	return &simGov{
-		validatorSet:          make(map[types.ValidatorID]decimal.Decimal),
-		expectedNumValidators: numValidators,
-	}
-}
-
-func (gov *simGov) GetValidatorSet() (
-	ret map[types.ValidatorID]decimal.Decimal) {
-
-	gov.lock.RLock()
-	defer gov.lock.RUnlock()
-
-	// Return the cloned validatorSet.
-	ret = make(map[types.ValidatorID]decimal.Decimal)
-	for k, v := range gov.validatorSet {
-		ret[k] = v
-	}
-	return
-}
-
-func (gov *simGov) GetBlockProposingInterval() int {
-	return 0
-}
-
-func (gov *simGov) GetMembershipEvents(epoch int) []types.MembershipEvent {
-	return nil
-}
-
-func (gov *simGov) addValidator(vID types.ValidatorID) {
-	gov.lock.Lock()
-	defer gov.lock.Unlock()
-
-	if _, exists := gov.validatorSet[vID]; exists {
-		return
-	}
-	if len(gov.validatorSet) == gov.expectedNumValidators {
-		panic(fmt.Errorf("attempt to add validator when ready"))
-	}
-	gov.validatorSet[vID] = decimal.NewFromFloat(0)
-}
diff --git a/simulation/governance.go b/simulation/governance.go
new file mode 100644
index 0000000..7e3f6f2
--- /dev/null
+++ b/simulation/governance.go
@@ -0,0 +1,99 @@
+// 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"
+
+	"github.com/dexon-foundation/dexon-consensus-core/core/types"
+	"github.com/dexon-foundation/dexon-consensus-core/simulation/config"
+	"github.com/shopspring/decimal"
+)
+
+// simGovernance is a simulated governance contract implementing the
+// core.Governance interface.
+type simGovernance struct {
+	lock                  sync.RWMutex
+	validatorSet          map[types.ValidatorID]decimal.Decimal
+	expectedNumValidators int
+	k                     int
+	phiRatio              float32
+}
+
+// newSimGovernance returns a new simGovernance instance.
+func newSimGovernance(
+	numValidators int, consensusConfig config.Consensus) *simGovernance {
+	return &simGovernance{
+		validatorSet:          make(map[types.ValidatorID]decimal.Decimal),
+		expectedNumValidators: numValidators,
+		k:        consensusConfig.K,
+		phiRatio: consensusConfig.PhiRatio,
+	}
+}
+
+// GetValidatorSet returns the validator set.
+func (g *simGovernance) GetValidatorSet() (
+	ret map[types.ValidatorID]decimal.Decimal) {
+
+	g.lock.RLock()
+	defer g.lock.RUnlock()
+
+	// Return the cloned validatorSet.
+	ret = make(map[types.ValidatorID]decimal.Decimal)
+	for k, v := range g.validatorSet {
+		ret[k] = v
+	}
+	return
+}
+
+// GetTotalOrderingK returns K.
+func (g *simGovernance) GetTotalOrderingK() int {
+	return g.k
+}
+
+// GetTotalOrderingK returns PhiRatio.
+func (g *simGovernance) GetPhiRatio() float32 {
+	return g.phiRatio
+}
+
+// GetBlockProposingInterval returns block proposing interval.
+func (g *simGovernance) GetBlockProposingInterval() int {
+	return 0
+}
+
+// GetConfigurationChangeEvent returns configuration change event since last
+// epoch.
+func (g *simGovernance) GetConfigurationChangeEvent(
+	epoch int) []types.ConfigurationChangeEvent {
+	return nil
+}
+
+// addValidator add a new validator into the simulated governance contract.
+func (g *simGovernance) addValidator(vID types.ValidatorID) {
+	g.lock.Lock()
+	defer g.lock.Unlock()
+
+	if _, exists := g.validatorSet[vID]; exists {
+		return
+	}
+	if len(g.validatorSet) == g.expectedNumValidators {
+		panic(fmt.Errorf("attempt to add validator when ready"))
+	}
+	g.validatorSet[vID] = decimal.NewFromFloat(0)
+}
diff --git a/simulation/validator.go b/simulation/validator.go
index 4bc8283..9a84908 100644
--- a/simulation/validator.go
+++ b/simulation/validator.go
@@ -31,8 +31,8 @@ import (
 // Validator represents a validator in DexCon.
 type Validator struct {
 	network Network
-	app     *SimApp
-	gov     *simGov
+	app     *simApp
+	gov     *simGovernance
 	db      blockdb.BlockDatabase
 
 	config     config.Validator
@@ -55,13 +55,13 @@ func NewValidator(
 	if err != nil {
 		panic(err)
 	}
-	gov := newSimGov(config.Num)
+	gov := newSimGovernance(config.Num, config.Consensus)
 	gov.addValidator(id)
 	return &Validator{
 		ID:         id,
 		config:     config,
 		network:    network,
-		app:        NewSimApp(id, network),
+		app:        newSimApp(id, network),
 		gov:        gov,
 		db:         db,
 		isFinished: make(chan struct{}),
diff --git a/test_config/test.toml b/test_config/test.toml
index 29067a4..0204ea1 100644
--- a/test_config/test.toml
+++ b/test_config/test.toml
@@ -6,6 +6,10 @@ propose_interval_mean = 5e+02
 propose_interval_sigma = 5e+0
 max_block = 20
 
+[validator.consensus]
+phi_ratio = 6.66670024394989e-01
+k = 2
+
 [networking]
 type = "tcp-local"
 peer_server = "peer.server"