兄弟连区块链教程源代码分析configupdate

兄弟连区块链教程Fabric1.0源代码分析configupdate处理通道配置更新，2018年下半年，区块链行业正逐渐褪去发展之初的浮躁、回归理性，表面上看相关人才需求与身价似乎正在回落。但事实上，正是初期泡沫的渐退，让人们更多的关注点放在了区块链真正的技术之上。

# Fabric 1.0源代码笔记 之 Orderer #configupdate（处理通道配置更新）

## 1、configupdate概述

configupdate，用于接收配置交易，并处理通道配置更新。

相关代码在orderer/configupdate目录。

## 2、SupportManager接口定义及实现

### 2.1、SupportManager接口定义

```go

type SupportManager interface {

GetChain(chainID string) (Support, bool)

NewChannelConfig(envConfigUpdate *cb.Envelope) (configtxapi.Manager, error)

}

//代码在orderer/configupdate/configupdate.go

```

### 2.2、SupportManager接口实现

SupportManager接口实现，即configUpdateSupport结构体及方法。

```go

type configUpdateSupport struct {

multichain.Manager //type multiLedger struct

}

func (cus configUpdateSupport) GetChain(chainID string) (configupdate.Support, bool) {

return cus.Manager.GetChain(chainID)

}

//代码在orderer/server.go

```

multichain.Manager接口及实现multiLedger，见Fabric 1.0源代码笔记 之 Orderer #multichain（多链支持包）

## 3、Support接口定义及实现

### 3.1、Support接口定义

```go

type Support interface {

ProposeConfigUpdate(env *cb.Envelope) (*cb.ConfigEnvelope, error)

}

//代码在orderer/configupdate/configupdate.go

```

### 3.2、Support接口实现

Support接口实现，即configManager结构体及方法。

```go

type configManager struct {

api.Resources

callOnUpdate []func(api.Manager)

initializer api.Initializer

current *configSet

}

func (cm *configManager) processConfig(channelGroup *cb.ConfigGroup) (*configResult, error) //./config.go

func (cm *configManager) commitCallbacks() //./manager.go

func (cm *configManager) ProposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error) //./manager.go

func (cm *configManager) proposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error) //./manager.go

func (cm *configManager) prepareApply(configEnv *cb.ConfigEnvelope) (*configResult, error) //./manager.go

func (cm *configManager) Validate(configEnv *cb.ConfigEnvelope) error //./manager.go

func (cm *configManager) Apply(configEnv *cb.ConfigEnvelope) error //./manager.go

func (cm *configManager) ChainID() string //./manager.go

func (cm *configManager) Sequence() uint64 //./manager.go

func (cm *configManager) ConfigEnvelope() *cb.ConfigEnvelope //./manager.go

func (cm *configManager) verifyDeltaSet(deltaSet map[string]comparable, signedData []*cb.SignedData) error //./update.go

func (cm *configManager) authorizeUpdate(configUpdateEnv *cb.ConfigUpdateEnvelope) (map[string]comparable, error) //./update.go

func (cm *configManager) policyForItem(item comparable) (policies.Policy, bool) //./update.go

func (cm *configManager) computeUpdateResult(updatedConfig map[string]comparable) map[string]comparable //./update.go

//代码在common/configtx/manager.go

```

## 4、ConfigUpdateProcessor接口定义及实现

### 4.1、ConfigUpdateProcessor接口定义

```go

type ConfigUpdateProcessor interface {

Process(envConfigUpdate *cb.Envelope) (*cb.Envelope, error)

}

//代码在orderer/common/broadcast/broadcast.go

```

### 4.2、ConfigUpdateProcessor接口实现

ConfigUpdateProcessor接口实现，即Processor结构体及方法。

```go

type Processor struct {

signer crypto.LocalSigner

manager SupportManager //即type configUpdateSupport struct，或者即multichain.multiLedger

systemChannelID string

systemChannelSupport Support

}

//构造Processor

func New(systemChannelID string, supportManager SupportManager, signer crypto.LocalSigner) *Processor

//获取channelID

func channelID(env *cb.Envelope) (string, error)

//处理通道配置更新

func (p *Processor) Process(envConfigUpdate *cb.Envelope) (*cb.Envelope, error)

func (p *Processor) existingChannelConfig(envConfigUpdate *cb.Envelope, channelID string, support Support) (*cb.Envelope, error)

func (p *Processor) proposeNewChannelToSystemChannel(newChannelEnvConfig *cb.Envelope) (*cb.Envelope, error)

func (p *Processor) newChannelConfig(channelID string, envConfigUpdate *cb.Envelope) (*cb.Envelope, error)

//代码在orderer/configupdate/configupdate.go

```

#### 4.2.1、func New(systemChannelID string, supportManager SupportManager, signer crypto.LocalSigner) *Processor

```go

func New(systemChannelID string, supportManager SupportManager, signer crypto.LocalSigner) *Processor {

support, ok := supportManager.GetChain(systemChannelID)

return &Processor{

systemChannelID: systemChannelID,

manager: supportManager,

signer: signer,

systemChannelSupport: support,

}

}

//代码在orderer/configupdate/configupdate.go

```

#### 4.2.2、func (p *Processor) Process(envConfigUpdate *cb.Envelope) (*cb.Envelope, error)

```go

func (p *Processor) Process(envConfigUpdate *cb.Envelope) (*cb.Envelope, error) {

channelID, err := channelID(envConfigUpdate)

support, ok := p.manager.GetChain(channelID) //存在

if ok {

return p.existingChannelConfig(envConfigUpdate, channelID, support)

}

return p.newChannelConfig(channelID, envConfigUpdate) //不存在

}

//代码在orderer/configupdate/configupdate.go

```

#### 4.2.3、func (p *Processor) existingChannelConfig(envConfigUpdate *cb.Envelope, channelID string, support Support) (*cb.Envelope, error)

```go

func (p *Processor) existingChannelConfig(envConfigUpdate *cb.Envelope, channelID string, support Support) (*cb.Envelope, error) {

configEnvelope, err := support.ProposeConfigUpdate(envConfigUpdate)

return utils.CreateSignedEnvelope(cb.HeaderType_CONFIG, channelID, p.signer, configEnvelope, msgVersion, epoch)

}

//代码在orderer/configupdate/configupdate.go

```

#### 4.2.4、func (p *Processor) newChannelConfig(channelID string, envConfigUpdate *cb.Envelope) (*cb.Envelope, error)

```go

func (p *Processor) newChannelConfig(channelID string, envConfigUpdate *cb.Envelope) (*cb.Envelope, error) {

ctxm, err := p.manager.NewChannelConfig(envConfigUpdate) //创建新的通道

newChannelConfigEnv, err := ctxm.ProposeConfigUpdate(envConfigUpdate) //创建新的通道后处理通道配置

newChannelEnvConfig, err := utils.CreateSignedEnvelope(cb.HeaderType_CONFIG, channelID, p.signer, newChannelConfigEnv, msgVersion, epoch)

return p.proposeNewChannelToSystemChannel(newChannelEnvConfig)

}

//代码在orderer/configupdate/configupdate.go

```

## 5、详解configManager结构体

### 5.1、configManager结构体定义及方法

```go

type configManager struct {

api.Resources

callOnUpdate []func(api.Manager)

initializer api.Initializer

current *configSet

}

func validateConfigID(configID string) error

func validateChannelID(channelID string) error

func NewManagerImpl(envConfig *cb.Envelope, initializer api.Initializer, callOnUpdate []func(api.Manager)) (api.Manager, error)

func (cm *configManager) commitCallbacks()

func (cm *configManager) ProposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error)

func (cm *configManager) proposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error)

func (cm *configManager) prepareApply(configEnv *cb.ConfigEnvelope) (*configResult, error)

func (cm *configManager) Validate(configEnv *cb.ConfigEnvelope) error

func (cm *configManager) Apply(configEnv *cb.ConfigEnvelope) error

func (cm *configManager) ChainID() string

func (cm *configManager) Sequence() uint64

func (cm *configManager) ConfigEnvelope() *cb.ConfigEnvelope

func proposeGroup(result *configResult) error

func processConfig(channelGroup *cb.ConfigGroup, proposer api.Proposer) (*configResult, error)

func (cm *configManager) processConfig(channelGroup *cb.ConfigGroup) (*configResult, error)

func (c *configSet) verifyReadSet(readSet map[string]comparable) error

func ComputeDeltaSet(readSet, writeSet map[string]comparable) map[string]comparable

func validateModPolicy(modPolicy string) error

func (cm *configManager) verifyDeltaSet(deltaSet map[string]comparable, signedData []*cb.SignedData) error

func verifyFullProposedConfig(writeSet, fullProposedConfig map[string]comparable) error

//验证所有修改的配置都有相应的修改策略，返回修改过的配置的映射map[string]comparable

func (cm *configManager) authorizeUpdate(configUpdateEnv *cb.ConfigUpdateEnvelope) (map[string]comparable, error)

func (cm *configManager) policyForItem(item comparable) (policies.Policy, bool)

func (cm *configManager) computeUpdateResult(updatedConfig map[string]comparable) map[string]comparable

//Envelope转换为ConfigUpdateEnvelope

func envelopeToConfigUpdate(configtx *cb.Envelope) (*cb.ConfigUpdateEnvelope, error)

//代码在common/configtx/manager.go

```

### 5.2、func (cm *configManager) ProposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error)

```go

func (cm *configManager) ProposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error) {

return cm.proposeConfigUpdate(configtx)

}

func (cm *configManager) proposeConfigUpdate(configtx *cb.Envelope) (*cb.ConfigEnvelope, error) {

//Envelope转换为ConfigUpdateEnvelope

configUpdateEnv, err := envelopeToConfigUpdate(configtx)

//验证所有修改的配置都有相应的修改策略，返回修改过的配置的映射map[string]comparable

configMap, err := cm.authorizeUpdate(configUpdateEnv)

channelGroup, err := configMapToConfig(configMap) //ConfigGroup

//实际调用processConfig(channelGroup, cm.initializer)，并最终调用proposeGroup(configResult)

result, err := cm.processConfig(channelGroup)

result.rollback()

return &cb.ConfigEnvelope{

Config: &cb.Config{

Sequence: cm.current.sequence + 1,

ChannelGroup: channelGroup,

},

LastUpdate: configtx,

}, nil

}

//代码在common/configtx/manager.go

```

补充ConfigUpdateEnvelope:

```go

type ConfigUpdateEnvelope struct {

ConfigUpdate []byte //type ConfigUpdate struct

Signatures []*ConfigSignature

}

type ConfigUpdate struct {

ChannelId string

ReadSet *ConfigGroup

WriteSet *ConfigGroup

}

type ConfigGroup struct {

Version uint64

Groups map[string]*ConfigGroup

Values map[string]*ConfigValue

Policies map[string]*ConfigPolicy

ModPolicy string

}

//代码在protos/common/configtx.pb.go

```

补充ConfigGroup:

```go

### 5.3、func (cm *configManager) authorizeUpdate(configUpdateEnv *cb.ConfigUpdateEnvelope) (map[string]comparable, error)

```go

func (cm *configManager) authorizeUpdate(configUpdateEnv *cb.ConfigUpdateEnvelope) (map[string]comparable, error) {

//反序列化configUpdateEnv.ConfigUpdate

configUpdate, err := UnmarshalConfigUpdate(configUpdateEnv.ConfigUpdate)

readSet, err := MapConfig(configUpdate.ReadSet) //map[string]comparable

err = cm.current.verifyReadSet(readSet)

writeSet, err := MapConfig(configUpdate.WriteSet) //map[string]comparable

//从writeSet中逐一对比readSet，去除没有发生变更的

deltaSet := ComputeDeltaSet(readSet, writeSet)

signedData, err := configUpdateEnv.AsSignedData() //转换为SignedData

err = cm.verifyDeltaSet(deltaSet, signedData) //校验deltaSet

fullProposedConfig := cm.computeUpdateResult(deltaSet) //合并为fullProposedConfig

err := verifyFullProposedConfig(writeSet, fullProposedConfig)

return fullProposedConfig, nil

}

//代码在common/configtx/update.go

```

补充comparable:

```go

type comparable struct {

*cb.ConfigGroup

*cb.ConfigValue

*cb.ConfigPolicy

key string

path []string

}

//代码在common/configtx/compare.go

```

### 5.4、func (cm *configManager) processConfig(channelGroup *cb.ConfigGroup) (*configResult, error)

```go

func (cm *configManager) processConfig(channelGroup *cb.ConfigGroup) (*configResult, error) {

configResult, err := processConfig(channelGroup, cm.initializer)

err = configResult.preCommit()

return configResult, nil

}

//代码在common/configtx/config.go

```

补充configResult：

```go

type configResult struct {

tx interface{}

groupName string

groupKey string

group *cb.ConfigGroup

valueHandler config.ValueProposer

policyHandler policies.Proposer

subResults []*configResult

deserializedValues map[string]proto.Message

deserializedPolicies map[string]proto.Message

}

func NewConfigResult(config *cb.ConfigGroup, proposer api.Proposer) (ConfigResult, error)

func (cr *configResult) JSON() string

func (cr *configResult) bufferJSON(buffer *bytes.Buffer)

//cr.valueHandler.PreCommit(cr.tx)

func (cr *configResult) preCommit() error

//cr.valueHandler.CommitProposals(cr.tx)

//cr.policyHandler.CommitProposals(cr.tx)

func (cr *configResult) commit()

//cr.valueHandler.RollbackProposals(cr.tx)

//cr.policyHandler.RollbackProposals(cr.tx)

func (cr *configResult) rollback()

func proposeGroup(result *configResult) error

func processConfig(channelGroup *cb.ConfigGroup, proposer api.Proposer) (*configResult, error)

//代码在common/configtx/config.go

```

#### 5.4.1、func processConfig(channelGroup *cb.ConfigGroup, proposer api.Proposer) (*configResult, error)

```go

func processConfig(channelGroup *cb.ConfigGroup, proposer api.Proposer) (*configResult, error) {

helperGroup := cb.NewConfigGroup()

helperGroup.Groups[RootGroupKey] = channelGroup

configResult := &configResult{

group: helperGroup,

valueHandler: proposer.ValueProposer(),

policyHandler: proposer.PolicyProposer(),

}

err := proposeGroup(configResult)

return configResult, nil

}

//代码在common/configtx/config.go

```

#### 5.4.2、func proposeGroup(result *configResult) error

```go

func proposeGroup(result *configResult) error {

subGroups := make([]string, len(result.group.Groups))

i := 0

for subGroup := range result.group.Groups {

subGroups[i] = subGroup

i++

}

valueDeserializer, subValueHandlers, err := result.valueHandler.BeginValueProposals(result.tx, subGroups)

subPolicyHandlers, err := result.policyHandler.BeginPolicyProposals(result.tx, subGroups)

for key, value := range result.group.Values {

msg, err := valueDeserializer.Deserialize(key, value.Value)

result.deserializedValues[key] = msg

}

for key, policy := range result.group.Policies {

policy, err := result.policyHandler.ProposePolicy(result.tx, key, policy)

result.deserializedPolicies[key] = policy

}

result.subResults = make([]*configResult, 0, len(subGroups))

for i, subGroup := range subGroups {

result.subResults = append(result.subResults, &configResult{

tx: result.tx,

groupKey: subGroup,

groupName: result.groupName + "/" + subGroup,

group: result.group.Groups[subGroup],

valueHandler: subValueHandlers[i],

policyHandler: subPolicyHandlers[i],

deserializedValues: make(map[string]proto.Message),

deserializedPolicies: make(map[string]proto.Message),

})

err := proposeGroup(result.subResults[i])

}

return nil

}

//代码在common/configtx/config.go

```

感谢关注兄弟连区块链教程分享！