4、交易相关部分工具函数（protos/utils包）
putils更详细内容，参考：Fabric 1.0源代码笔记 之 putils（protos/utils工具包）
5、RWSet（读写集）
RWSet更详细内容，参考：Fabric 1.0源代码笔记 之 Tx #RWSet（读写集）
6、version.Height结构体及方法
type Height struct {BlockNum uint64 //区块编号TxNum uint64 //交易编号}func NewHeight(blockNum, txNum uint64) *Height //构造Heightfunc NewHeightFromBytes(b []byte) (*Height, int) //[]byte反序列化构造Heightfunc (h *Height) ToBytes() []byte //Height序列化func (h *Height) Compare(h1 *Height) int //比较两个Heightfunc AreSame(h1 *Height, h2 *Height) bool //比较两个Height是否相等//代码在core/ledger/kvledger/txmgmt/version/version.go
7、Validator接口及实现（验证读写集）
7.1、Validator接口定义
type Validator interface {//验证和准备批处理ValidateAndPrepareBatch(block *common.Block, doMVCCValidation bool) (*statedb.UpdateBatch, error)}//代码在core/ledger/kvledger/txmgmt/validator/validator.go
7.2、Validator接口实现
Validator接口实现，即statebasedval.Validator结构体及方法。Validator结构体定义如下：
type Validator struct {db statedb.VersionedDB //statedb}//代码在core/ledger/kvledger/txmgmt/validator/statebasedval/state_based_validator.go
涉及方法如下：
//构造Validatorfunc NewValidator(db statedb.VersionedDB) *Validator//验证背书交易func (v *Validator) validateEndorserTX(envBytes []byte, doMVCCValidation bool, updates *statedb.UpdateBatch) (*rwsetutil.TxRwSet, peer.TxValidationCode, error)//验证和准备批处理，Block中写集加入批处理func (v *Validator) ValidateAndPrepareBatch(block *common.Block, doMVCCValidation bool) (*statedb.UpdateBatch, error)func addWriteSetToBatch(txRWSet *rwsetutil.TxRwSet, txHeight *version.Height, batch *statedb.UpdateBatch)func (v *Validator) validateTx(txRWSet *rwsetutil.TxRwSet, updates *statedb.UpdateBatch) (peer.TxValidationCode, error)func (v *Validator) validateReadSet(ns string, kvReads []*kvrwset.KVRead, updates *statedb.UpdateBatch) (bool, error)func (v *Validator) validateKVRead(ns string, kvRead *kvrwset.KVRead, updates *statedb.UpdateBatch) (bool, error)func (v *Validator) validateRangeQueries(ns string, rangeQueriesInfo []*kvrwset.RangeQueryInfo, updates *statedb.UpdateBatch) (bool, error)func (v *Validator) validateRangeQuery(ns string, rangeQueryInfo *kvrwset.RangeQueryInfo, updates *statedb.UpdateBatch) (bool, error)//代码在core/ledger/kvledger/txmgmt/validator/statebasedval/state_based_validator.go
func (vValidator) ValidateAndPrepareBatch(blockcommon.Block, doMVCCValidation bool) (*statedb.UpdateBatch, error)代码如下：
updates := statedb.NewUpdateBatch() //构造批处理//type TxValidationFlags []uint8txsFilter := util.TxValidationFlags(block.Metadata.Metadata[common.BlockMetadataIndex_TRANSACTIONS_FILTER])if len(txsFilter) == 0 {txsFilter = util.NewTxValidationFlags(len(block.Data.Data))block.Metadata.Metadata[common.BlockMetadataIndex_TRANSACTIONS_FILTER] = txsFilter}for txIndex, envBytes := range block.Data.Data {if txsFilter.IsInvalid(txIndex) { //验证交易是否有效continue}env, err := putils.GetEnvelopeFromBlock(envBytes) //Envelopepayload, err := putils.GetPayload(env) //Payloadchdr, err := putils.UnmarshalChannelHeader(payload.Header.ChannelHeader) //ChannelHeadertxType := common.HeaderType(chdr.Type) //HeaderTypeif txType != common.HeaderType_ENDORSER_TRANSACTION {continue}//验证背书交易，获取读写集txRWSet, txResult, err := v.validateEndorserTX(envBytes, doMVCCValidation, updates)txsFilter.SetFlag(txIndex, txResult)if txRWSet != nil {committingTxHeight := version.NewHeight(block.Header.Number, uint64(txIndex))//读写集中写集加入批处理addWriteSetToBatch(txRWSet, committingTxHeight, updates)txsFilter.SetFlag(txIndex, peer.TxValidationCode_VALID)}}block.Metadata.Metadata[common.BlockMetadataIndex_TRANSACTIONS_FILTER] = txsFilterreturn updates, nil//代码在core/ledger/kvledger/txmgmt/validator/statebasedval/state_based_validator.go
8、TxMgr接口及实现（交易管理）
8.1、TxMgr接口定义
type TxMgr interface {NewQueryExecutor() (ledger.QueryExecutor, error)NewTxSimulator() (ledger.TxSimulator, error)ValidateAndPrepare(block *common.Block, doMVCCValidation bool) error//返回statedb一致的最高事务的高度GetLastSavepoint() (*version.Height, error)ShouldRecover(lastAvailableBlock uint64) (bool, uint64, error)CommitLostBlock(block *common.Block) errorCommit() errorRollback()Shutdown()}//代码在core/ledger/kvledger/txmgmt/txmgr/txmgr.go
8.2、TxMgr接口实现
TxMgr接口实现，即LockBasedTxMgr结构体及方法。LockBasedTxMgr结构体如下：
type LockBasedTxMgr struct {db statedb.VersionedDB //statedbvalidator validator.Validator //Validatorbatch *statedb.UpdateBatch //批处理currentBlock *common.Block //BlockcommitRWLock sync.RWMutex //锁}//代码在core/ledger/kvledger/txmgmt/txmgr/lockbasedtxmgr/lockbased_txmgr.go
涉及方法如下：
//构造LockBasedTxMgrfunc NewLockBasedTxMgr(db statedb.VersionedDB) *LockBasedTxMgr//调取txmgr.db.GetLatestSavePoint()，返回statedb一致的最高事务的高度func (txmgr *LockBasedTxMgr) GetLastSavepoint() (*version.Height, error)//调取newQueryExecutor(txmgr)func (txmgr *LockBasedTxMgr) NewQueryExecutor() (ledger.QueryExecutor, error)func (txmgr *LockBasedTxMgr) NewTxSimulator() (ledger.TxSimulator, error)//验证Block，并从Block中获取写集加入批处理txmgr.batchfunc (txmgr *LockBasedTxMgr) ValidateAndPrepare(block *common.Block, doMVCCValidation bool) errorfunc (txmgr *LockBasedTxMgr) Shutdown()//执行txmgr.batch，func (txmgr *LockBasedTxMgr) Commit() errorfunc (txmgr *LockBasedTxMgr) Rollback()func (txmgr *LockBasedTxMgr) ShouldRecover(lastAvailableBlock uint64) (bool, uint64, error)func (txmgr *LockBasedTxMgr) CommitLostBlock(block *common.Block) error//代码在core/ledger/kvledger/txmgmt/txmgr/lockbasedtxmgr/lockbased_txmgr.go
8.3、lockBasedQueryExecutor结构体及方法（实现ledger.QueryExecutor接口）
type lockBasedQueryExecutor struct {helper *queryHelperidstring}func newQueryExecutor(txmgr *LockBasedTxMgr) *lockBasedQueryExecutor func (q *lockBasedQueryExecutor) GetState(ns string, key string) ([]byte, error)func (q *lockBasedQueryExecutor) GetStateMultipleKeys(namespace string, keys []string) ([][]byte, error)func (q *lockBasedQueryExecutor) GetStateRangeScanIterator(namespace string, startKey string, endKey string) (ledger.ResultsIterator, error)func (q *lockBasedQueryExecutor) ExecuteQuery(namespace, query string) (ledger.ResultsIterator, error)func (q *lockBasedQueryExecutor) Done()//代码在core/ledger/kvledger/txmgmt/txmgr/lockbasedtxmgr/lockbased_query_executer.go
8.4、queryHelper结构体及方法
queryHelper结构体及方法：
type queryHelper struct {txmgr *LockBasedTxMgr //LockBasedTxMgrrwsetBuilder *rwsetutil.RWSetBuilder //读写集工具itrs []*resultsItrerrerrordoneInvoked bool //是否调用完成}//statedb中获取versionedValue，并加入rwsetBuilder的nsRWs.readMap中func (h *queryHelper) getState(ns string, key string) ([]byte, error)//statedb中获取多个versionedValue，并加入rwsetBuilder的nsRWs.readMap中func (h *queryHelper) getStateMultipleKeys(namespace string, keys []string) ([][]byte, error)//构造resultsItr，并加入queryHelper.itrsfunc (h *queryHelper) getStateRangeScanIterator(namespace string, startKey string, endKey string) (commonledger.ResultsIterator, error)执行查询并构造queryResultsItrfunc (h *queryHelper) executeQuery(namespace, query string) (commonledger.ResultsIterator, error)//donefunc (h *queryHelper) done()func (h *queryHelper) checkDone()//代码在core/ledger/kvledger/txmgmt/txmgr/lockbasedtxmgr/helper.go
resultsItr结构体及方法：
type resultsItr struct {ns stringendKey stringdbItr statedb.ResultsIteratorrwSetBuilder *rwsetutil.RWSetBuilderrangeQueryInfo*kvrwset.RangeQueryInforangeQueryResultsHelper *rwsetutil.RangeQueryResultsHelper}func newResultsItr(ns string, startKey string, endKey string, db statedb.VersionedDB, rwsetBuilder *rwsetutil.RWSetBuilder, enableHashing bool, maxDegree uint32) (*resultsItr, error)func (itr *resultsItr) Next() (commonledger.QueryResult, error)func (itr *resultsItr) updateRangeQueryInfo(queryResult statedb.QueryResult)func (itr *resultsItr) Close()//代码在core/ledger/kvledger/txmgmt/txmgr/lockbasedtxmgr/helper.go感谢关注兄弟连区块链教程分享！
