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statecouchdb.go
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statecouchdb.go
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/*
Copyright IBM Corp. All Rights Reserved.
SPDX-License-Identifier: Apache-2.0
*/
package statecouchdb
import (
"bytes"
"context"
"encoding/json"
"fmt"
"sync"
"github.com/mcc-github/blockchain/common/flogging"
"github.com/mcc-github/blockchain/common/metrics"
"github.com/mcc-github/blockchain/core/common/ccprovider"
"github.com/mcc-github/blockchain/core/ledger/kvledger/txmgmt/statedb"
"github.com/mcc-github/blockchain/core/ledger/kvledger/txmgmt/version"
"github.com/mcc-github/blockchain/core/ledger/util/couchdb"
"github.com/pkg/errors"
)
var logger = flogging.MustGetLogger("statecouchdb")
const lsccCacheSize = 50
type VersionedDBProvider struct {
couchInstance *couchdb.CouchInstance
databases map[string]*VersionedDB
mux sync.Mutex
openCounts uint64
redoLoggerProvider *redoLoggerProvider
}
func NewVersionedDBProvider(config *couchdb.Config, metricsProvider metrics.Provider) (*VersionedDBProvider, error) {
logger.Debugf("constructing CouchDB VersionedDBProvider")
couchInstance, err := couchdb.CreateCouchInstance(config, metricsProvider)
if err != nil {
return nil, err
}
p, err := newRedoLoggerProvider(config.RedoLogPath)
if err != nil {
return nil, err
}
return &VersionedDBProvider{
couchInstance: couchInstance,
databases: make(map[string]*VersionedDB),
mux: sync.Mutex{},
openCounts: 0,
redoLoggerProvider: p,
},
nil
}
func (provider *VersionedDBProvider) GetDBHandle(dbName string) (statedb.VersionedDB, error) {
provider.mux.Lock()
defer provider.mux.Unlock()
vdb := provider.databases[dbName]
if vdb == nil {
var err error
vdb, err = newVersionedDB(
provider.couchInstance,
provider.redoLoggerProvider.newRedoLogger(dbName),
dbName,
)
if err != nil {
return nil, err
}
provider.databases[dbName] = vdb
}
return vdb, nil
}
func (provider *VersionedDBProvider) Close() {
provider.redoLoggerProvider.close()
}
func (provider *VersionedDBProvider) HealthCheck(ctx context.Context) error {
return provider.couchInstance.HealthCheck(ctx)
}
type VersionedDB struct {
couchInstance *couchdb.CouchInstance
metadataDB *couchdb.CouchDatabase
chainName string
namespaceDBs map[string]*couchdb.CouchDatabase
committedDataCache *versionsCache
verCacheLock sync.RWMutex
mux sync.RWMutex
lsccStateCache *lsccStateCache
redoLogger *redoLogger
}
type lsccStateCache struct {
cache map[string]*statedb.VersionedValue
rwMutex sync.RWMutex
}
func (l *lsccStateCache) getState(key string) *statedb.VersionedValue {
l.rwMutex.RLock()
defer l.rwMutex.RUnlock()
if versionedValue, ok := l.cache[key]; ok {
logger.Debugf("key:[%s] found in the lsccStateCache", key)
return versionedValue
}
return nil
}
func (l *lsccStateCache) updateState(key string, value *statedb.VersionedValue) {
l.rwMutex.Lock()
defer l.rwMutex.Unlock()
if _, ok := l.cache[key]; ok {
logger.Debugf("key:[%s] is updated in lsccStateCache", key)
l.cache[key] = value
}
}
func (l *lsccStateCache) setState(key string, value *statedb.VersionedValue) {
l.rwMutex.Lock()
defer l.rwMutex.Unlock()
if l.isCacheFull() {
l.evictARandomEntry()
}
logger.Debugf("key:[%s] is stoed in lsccStateCache", key)
l.cache[key] = value
}
func (l *lsccStateCache) isCacheFull() bool {
return len(l.cache) == lsccCacheSize
}
func (l *lsccStateCache) evictARandomEntry() {
for key := range l.cache {
delete(l.cache, key)
return
}
}
func newVersionedDB(couchInstance *couchdb.CouchInstance, redoLogger *redoLogger, dbName string) (*VersionedDB, error) {
chainName := dbName
dbName = couchdb.ConstructMetadataDBName(dbName)
metadataDB, err := couchdb.CreateCouchDatabase(couchInstance, dbName)
if err != nil {
return nil, err
}
namespaceDBMap := make(map[string]*couchdb.CouchDatabase)
vdb := &VersionedDB{
couchInstance: couchInstance,
metadataDB: metadataDB,
chainName: chainName,
namespaceDBs: namespaceDBMap,
committedDataCache: newVersionCache(),
lsccStateCache: &lsccStateCache{
cache: make(map[string]*statedb.VersionedValue),
},
redoLogger: redoLogger,
}
logger.Debugf("chain [%s]: checking for redolog record", chainName)
redologRecord, err := redoLogger.load()
if err != nil {
return nil, err
}
savepoint, err := vdb.GetLatestSavePoint()
if err != nil {
return nil, err
}
if redologRecord == nil || savepoint == nil {
logger.Debugf("chain [%s]: No redo-record or save point present", chainName)
return vdb, nil
}
logger.Debugf("chain [%s]: save point = %#v, version of redolog record = %#v",
chainName, savepoint, redologRecord.Version)
if redologRecord.Version.BlockNum-savepoint.BlockNum == 1 {
logger.Debugf("chain [%s]: Re-applying last batch", chainName)
if err := vdb.applyUpdates(redologRecord.UpdateBatch, redologRecord.Version); err != nil {
return nil, err
}
}
return vdb, nil
}
func (vdb *VersionedDB) getNamespaceDBHandle(namespace string) (*couchdb.CouchDatabase, error) {
vdb.mux.RLock()
db := vdb.namespaceDBs[namespace]
vdb.mux.RUnlock()
if db != nil {
return db, nil
}
namespaceDBName := couchdb.ConstructNamespaceDBName(vdb.chainName, namespace)
vdb.mux.Lock()
defer vdb.mux.Unlock()
db = vdb.namespaceDBs[namespace]
if db == nil {
var err error
db, err = couchdb.CreateCouchDatabase(vdb.couchInstance, namespaceDBName)
if err != nil {
return nil, err
}
vdb.namespaceDBs[namespace] = db
}
return db, nil
}
func (vdb *VersionedDB) ProcessIndexesForChaincodeDeploy(namespace string, fileEntries []*ccprovider.TarFileEntry) error {
db, err := vdb.getNamespaceDBHandle(namespace)
if err != nil {
return err
}
for _, fileEntry := range fileEntries {
indexData := fileEntry.FileContent
filename := fileEntry.FileHeader.Name
_, err = db.CreateIndex(string(indexData))
if err != nil {
return errors.WithMessagef(err, "error creating index from file [%s] for channel [%s]", filename, namespace)
}
}
return nil
}
func (vdb *VersionedDB) GetDBType() string {
return "couchdb"
}
func (vdb *VersionedDB) LoadCommittedVersions(keys []*statedb.CompositeKey) error {
nsKeysMap := map[string][]string{}
committedDataCache := newVersionCache()
for _, compositeKey := range keys {
ns, key := compositeKey.Namespace, compositeKey.Key
committedDataCache.setVerAndRev(ns, key, nil, "")
logger.Debugf("Load into version cache: %s~%s", ns, key)
nsKeysMap[ns] = append(nsKeysMap[ns], key)
}
nsMetadataMap, err := vdb.retrieveMetadata(nsKeysMap)
logger.Debugf("nsKeysMap=%s", nsKeysMap)
logger.Debugf("nsMetadataMap=%s", nsMetadataMap)
if err != nil {
return err
}
for ns, nsMetadata := range nsMetadataMap {
for _, keyMetadata := range nsMetadata {
if len(keyMetadata.Version) != 0 {
version, _, err := decodeVersionAndMetadata(keyMetadata.Version)
if err != nil {
return err
}
committedDataCache.setVerAndRev(ns, keyMetadata.ID, version, keyMetadata.Rev)
}
}
}
vdb.verCacheLock.Lock()
defer vdb.verCacheLock.Unlock()
vdb.committedDataCache = committedDataCache
return nil
}
func (vdb *VersionedDB) GetVersion(namespace string, key string) (*version.Height, error) {
returnVersion, keyFound := vdb.GetCachedVersion(namespace, key)
if !keyFound {
vv, err := vdb.GetState(namespace, key)
if err != nil || vv == nil {
return nil, err
}
returnVersion = vv.Version
}
return returnVersion, nil
}
func (vdb *VersionedDB) GetCachedVersion(namespace string, key string) (*version.Height, bool) {
logger.Debugf("Retrieving cached version: %s~%s", key, namespace)
vdb.verCacheLock.RLock()
defer vdb.verCacheLock.RUnlock()
return vdb.committedDataCache.getVersion(namespace, key)
}
func (vdb *VersionedDB) ValidateKeyValue(key string, value []byte) error {
err := validateKey(key)
if err != nil {
return err
}
return validateValue(value)
}
func (vdb *VersionedDB) BytesKeySupported() bool {
return false
}
func (vdb *VersionedDB) GetState(namespace string, key string) (*statedb.VersionedValue, error) {
logger.Debugf("GetState(). ns=%s, key=%s", namespace, key)
if namespace == "lscc" {
if value := vdb.lsccStateCache.getState(key); value != nil {
return value, nil
}
}
db, err := vdb.getNamespaceDBHandle(namespace)
if err != nil {
return nil, err
}
couchDoc, _, err := db.ReadDoc(key)
if err != nil {
return nil, err
}
if couchDoc == nil {
return nil, nil
}
kv, err := couchDocToKeyValue(couchDoc)
if err != nil {
return nil, err
}
if namespace == "lscc" {
vdb.lsccStateCache.setState(key, kv.VersionedValue)
}
return kv.VersionedValue, nil
}
func (vdb *VersionedDB) GetStateMultipleKeys(namespace string, keys []string) ([]*statedb.VersionedValue, error) {
vals := make([]*statedb.VersionedValue, len(keys))
for i, key := range keys {
val, err := vdb.GetState(namespace, key)
if err != nil {
return nil, err
}
vals[i] = val
}
return vals, nil
}
func (vdb *VersionedDB) GetStateRangeScanIterator(namespace string, startKey string, endKey string) (statedb.ResultsIterator, error) {
return vdb.GetStateRangeScanIteratorWithMetadata(namespace, startKey, endKey, nil)
}
const optionBookmark = "bookmark"
const optionLimit = "limit"
func (vdb *VersionedDB) GetStateRangeScanIteratorWithMetadata(namespace string, startKey string, endKey string, metadata map[string]interface{}) (statedb.QueryResultsIterator, error) {
logger.Debugf("Entering GetStateRangeScanIteratorWithMetadata namespace: %s startKey: %s endKey: %s metadata: %v", namespace, startKey, endKey, metadata)
internalQueryLimit := vdb.couchInstance.InternalQueryLimit()
requestedLimit := int32(0)
if metadata != nil {
err := statedb.ValidateRangeMetadata(metadata)
if err != nil {
return nil, err
}
if limitOption, ok := metadata[optionLimit]; ok {
requestedLimit = limitOption.(int32)
}
}
db, err := vdb.getNamespaceDBHandle(namespace)
if err != nil {
return nil, err
}
return newQueryScanner(namespace, db, "", internalQueryLimit, requestedLimit, "", startKey, endKey)
}
func (scanner *queryScanner) getNextStateRangeScanResults() error {
queryLimit := scanner.queryDefinition.internalQueryLimit
if scanner.paginationInfo.requestedLimit > 0 {
moreResultsNeeded := scanner.paginationInfo.requestedLimit - scanner.resultsInfo.totalRecordsReturned
if moreResultsNeeded < scanner.queryDefinition.internalQueryLimit {
queryLimit = moreResultsNeeded
}
}
queryResult, nextStartKey, err := rangeScanFilterCouchInternalDocs(scanner.db,
scanner.queryDefinition.startKey, scanner.queryDefinition.endKey, queryLimit)
if err != nil {
return err
}
scanner.resultsInfo.results = queryResult
scanner.queryDefinition.startKey = nextStartKey
scanner.paginationInfo.cursor = 0
return nil
}
func rangeScanFilterCouchInternalDocs(db *couchdb.CouchDatabase,
startKey, endKey string, queryLimit int32,
) ([]*couchdb.QueryResult, string, error) {
var finalResults []*couchdb.QueryResult
var finalNextStartKey string
for {
results, nextStartKey, err := db.ReadDocRange(startKey, endKey, queryLimit)
if err != nil {
logger.Debugf("Error calling ReadDocRange(): %s\n", err.Error())
return nil, "", err
}
var filteredResults []*couchdb.QueryResult
for _, doc := range results {
if !isCouchInternalKey(doc.ID) {
filteredResults = append(filteredResults, doc)
}
}
finalResults = append(finalResults, filteredResults...)
finalNextStartKey = nextStartKey
queryLimit = int32(len(results) - len(filteredResults))
if queryLimit == 0 || finalNextStartKey == "" {
break
}
startKey = finalNextStartKey
}
var err error
for i := 0; isCouchInternalKey(finalNextStartKey); i++ {
_, finalNextStartKey, err = db.ReadDocRange(finalNextStartKey, endKey, 1)
logger.Debugf("i=%d, finalNextStartKey=%s", i, finalNextStartKey)
if err != nil {
return nil, "", err
}
}
return finalResults, finalNextStartKey, nil
}
func isCouchInternalKey(key string) bool {
return len(key) != 0 && key[0] == '_'
}
func (vdb *VersionedDB) ExecuteQuery(namespace, query string) (statedb.ResultsIterator, error) {
queryResult, err := vdb.ExecuteQueryWithMetadata(namespace, query, nil)
if err != nil {
return nil, err
}
return queryResult, nil
}
func (vdb *VersionedDB) ExecuteQueryWithMetadata(namespace, query string, metadata map[string]interface{}) (statedb.QueryResultsIterator, error) {
logger.Debugf("Entering ExecuteQueryWithMetadata namespace: %s, query: %s, metadata: %v", namespace, query, metadata)
internalQueryLimit := vdb.couchInstance.InternalQueryLimit()
bookmark := ""
requestedLimit := int32(0)
if metadata != nil {
err := validateQueryMetadata(metadata)
if err != nil {
return nil, err
}
if limitOption, ok := metadata[optionLimit]; ok {
requestedLimit = limitOption.(int32)
}
if bookmarkOption, ok := metadata[optionBookmark]; ok {
bookmark = bookmarkOption.(string)
}
}
queryString, err := applyAdditionalQueryOptions(query, internalQueryLimit, bookmark)
if err != nil {
logger.Errorf("Error calling applyAdditionalQueryOptions(): %s", err.Error())
return nil, err
}
db, err := vdb.getNamespaceDBHandle(namespace)
if err != nil {
return nil, err
}
return newQueryScanner(namespace, db, queryString, internalQueryLimit, requestedLimit, bookmark, "", "")
}
func (scanner *queryScanner) executeQueryWithBookmark() error {
queryLimit := scanner.queryDefinition.internalQueryLimit
if scanner.paginationInfo.requestedLimit > 0 {
if scanner.paginationInfo.requestedLimit-scanner.resultsInfo.totalRecordsReturned < scanner.queryDefinition.internalQueryLimit {
queryLimit = scanner.paginationInfo.requestedLimit - scanner.resultsInfo.totalRecordsReturned
}
}
queryString, err := applyAdditionalQueryOptions(scanner.queryDefinition.query,
queryLimit, scanner.paginationInfo.bookmark)
if err != nil {
logger.Debugf("Error calling applyAdditionalQueryOptions(): %s\n", err.Error())
return err
}
queryResult, bookmark, err := scanner.db.QueryDocuments(queryString)
if err != nil {
logger.Debugf("Error calling QueryDocuments(): %s\n", err.Error())
return err
}
scanner.resultsInfo.results = queryResult
scanner.paginationInfo.bookmark = bookmark
scanner.paginationInfo.cursor = 0
return nil
}
func validateQueryMetadata(metadata map[string]interface{}) error {
for key, keyVal := range metadata {
switch key {
case optionBookmark:
if _, ok := keyVal.(string); ok {
continue
}
return fmt.Errorf("Invalid entry, \"bookmark\" must be a string")
case optionLimit:
if _, ok := keyVal.(int32); ok {
continue
}
return fmt.Errorf("Invalid entry, \"limit\" must be an int32")
default:
return fmt.Errorf("Invalid entry, option %s not recognized", key)
}
}
return nil
}
func (vdb *VersionedDB) ApplyUpdates(updates *statedb.UpdateBatch, height *version.Height) error {
if height != nil && updates.ContainsPostOrderWrites {
r := &redoRecord{
UpdateBatch: updates,
Version: height,
}
if err := vdb.redoLogger.persist(r); err != nil {
return err
}
}
return vdb.applyUpdates(updates, height)
}
func (vdb *VersionedDB) applyUpdates(updates *statedb.UpdateBatch, height *version.Height) error {
var updateBatches []batch
var err error
if updateBatches, err = vdb.buildCommitters(updates); err != nil {
return err
}
if err = executeBatches(updateBatches); err != nil {
return err
}
namespaces := updates.GetUpdatedNamespaces()
if err = vdb.ensureFullCommitAndRecordSavepoint(height, namespaces); err != nil {
logger.Errorf("Error during recordSavepoint: %s", err.Error())
return err
}
lsccUpdates := updates.GetUpdates("lscc")
for key, value := range lsccUpdates {
vdb.lsccStateCache.updateState(key, value)
}
return nil
}
func (vdb *VersionedDB) ClearCachedVersions() {
logger.Debugf("Clear Cache")
vdb.verCacheLock.Lock()
defer vdb.verCacheLock.Unlock()
vdb.committedDataCache = newVersionCache()
}
func (vdb *VersionedDB) Open() error {
return nil
}
func (vdb *VersionedDB) Close() {
}
const savepointDocID = "statedb_savepoint"
func (vdb *VersionedDB) ensureFullCommitAndRecordSavepoint(height *version.Height, namespaces []string) error {
var dbs []*couchdb.CouchDatabase
for _, ns := range namespaces {
db, err := vdb.getNamespaceDBHandle(ns)
if err != nil {
return err
}
dbs = append(dbs, db)
}
if err := vdb.ensureFullCommit(dbs); err != nil {
return err
}
if height == nil {
return nil
}
savepointCouchDoc, err := encodeSavepoint(height)
if err != nil {
return err
}
_, err = vdb.metadataDB.SaveDoc(savepointDocID, "", savepointCouchDoc)
if err != nil {
logger.Errorf("Failed to save the savepoint to DB %s", err.Error())
return err
}
return nil
}
func (vdb *VersionedDB) GetLatestSavePoint() (*version.Height, error) {
var err error
couchDoc, _, err := vdb.metadataDB.ReadDoc(savepointDocID)
if err != nil {
logger.Errorf("Failed to read savepoint data %s", err.Error())
return nil, err
}
if couchDoc == nil || couchDoc.JSONValue == nil {
return nil, nil
}
return decodeSavepoint(couchDoc)
}
func applyAdditionalQueryOptions(queryString string, queryLimit int32, queryBookmark string) (string, error) {
const jsonQueryFields = "fields"
const jsonQueryLimit = "limit"
const jsonQueryBookmark = "bookmark"
jsonQueryMap := make(map[string]interface{})
decoder := json.NewDecoder(bytes.NewBuffer([]byte(queryString)))
decoder.UseNumber()
err := decoder.Decode(&jsonQueryMap)
if err != nil {
return "", err
}
if fieldsJSONArray, ok := jsonQueryMap[jsonQueryFields]; ok {
switch fieldsJSONArray.(type) {
case []interface{}:
jsonQueryMap[jsonQueryFields] = append(fieldsJSONArray.([]interface{}),
idField, versionField)
default:
return "", errors.New("fields definition must be an array")
}
}
jsonQueryMap[jsonQueryLimit] = queryLimit
if queryBookmark != "" {
jsonQueryMap[jsonQueryBookmark] = queryBookmark
}
editedQuery, err := json.Marshal(jsonQueryMap)
if err != nil {
return "", err
}
logger.Debugf("Rewritten query: %s", editedQuery)
return string(editedQuery), nil
}
type queryScanner struct {
namespace string
db *couchdb.CouchDatabase
queryDefinition *queryDefinition
paginationInfo *paginationInfo
resultsInfo *resultsInfo
}
type queryDefinition struct {
startKey string
endKey string
query string
internalQueryLimit int32
}
type paginationInfo struct {
cursor int32
requestedLimit int32
bookmark string
}
type resultsInfo struct {
totalRecordsReturned int32
results []*couchdb.QueryResult
}
func newQueryScanner(namespace string, db *couchdb.CouchDatabase, query string, internalQueryLimit,
limit int32, bookmark, startKey, endKey string) (*queryScanner, error) {
scanner := &queryScanner{namespace, db, &queryDefinition{startKey, endKey, query, internalQueryLimit}, &paginationInfo{-1, limit, bookmark}, &resultsInfo{0, nil}}
var err error
if scanner.queryDefinition.query != "" {
err = scanner.executeQueryWithBookmark()
} else {
err = scanner.getNextStateRangeScanResults()
}
if err != nil {
return nil, err
}
scanner.paginationInfo.cursor = -1
return scanner, nil
}
func (scanner *queryScanner) Next() (statedb.QueryResult, error) {
if len(scanner.resultsInfo.results) == 0 {
return nil, nil
}
scanner.paginationInfo.cursor++
if scanner.paginationInfo.cursor >= scanner.queryDefinition.internalQueryLimit {
var err error
if scanner.queryDefinition.query != "" {
err = scanner.executeQueryWithBookmark()
} else {
err = scanner.getNextStateRangeScanResults()
}
if err != nil {
return nil, err
}
if len(scanner.resultsInfo.results) == 0 {
return nil, nil
}
}
if scanner.paginationInfo.cursor >= int32(len(scanner.resultsInfo.results)) {
return nil, nil
}
selectedResultRecord := scanner.resultsInfo.results[scanner.paginationInfo.cursor]
key := selectedResultRecord.ID
kv, err := couchDocToKeyValue(&couchdb.CouchDoc{JSONValue: selectedResultRecord.Value, Attachments: selectedResultRecord.Attachments})
if err != nil {
return nil, err
}
scanner.resultsInfo.totalRecordsReturned++
return &statedb.VersionedKV{
CompositeKey: statedb.CompositeKey{Namespace: scanner.namespace, Key: key},
VersionedValue: *kv.VersionedValue}, nil
}
func (scanner *queryScanner) Close() {
scanner = nil
}
func (scanner *queryScanner) GetBookmarkAndClose() string {
retval := ""
if scanner.queryDefinition.query != "" {
retval = scanner.paginationInfo.bookmark
} else {
retval = scanner.queryDefinition.startKey
}
scanner.Close()
return retval
}