refactor(*): migrate boltdb to factory pattern

dtmsvr/storage/boltdb/boltdb.go

@@ -9,48 +9,50 @@ package boltdb
 import (
 	"fmt"
 	"strings"
-	"sync"
 	"time"
 
 	bolt "go.etcd.io/bbolt"
 
 	"github.com/dtm-labs/dtm/dtmcli/dtmimp"
 	"github.com/dtm-labs/dtm/dtmcli/logger"
-	"github.com/dtm-labs/dtm/dtmsvr/config"
 	"github.com/dtm-labs/dtm/dtmsvr/storage"
 	"github.com/dtm-labs/dtm/dtmutil"
 )
 
-var conf = &config.Config
-
 // Store implements storage.Store, and storage with boltdb
 type Store struct {
+	boltDb *bolt.DB
+
+	dataExpire    int64
+	retryInterval int64
 }
 
-var boltDb *bolt.DB
-var boltOnce sync.Once
+// NewStore will return the boltdb implement
+// TODO: change to options
+func NewStore(dataExpire int64, retryInterval int64) *Store {
+	s := &Store{
+		dataExpire:    dataExpire,
+		retryInterval: retryInterval,
+	}
 
-func boltGet() *bolt.DB {
-	boltOnce.Do(func() {
-		db, err := bolt.Open("./dtm.bolt", 0666, &bolt.Options{Timeout: 1 * time.Second})
-		dtmimp.E2P(err)
+	db, err := bolt.Open("./dtm.bolt", 0666, &bolt.Options{Timeout: 1 * time.Second})
+	dtmimp.E2P(err)
 
-		// NOTE: we must ensure all buckets is exists before we use it
-		err = initializeBuckets(db)
-		dtmimp.E2P(err)
+	// NOTE: we must ensure all buckets is exists before we use it
+	err = initializeBuckets(db)
+	dtmimp.E2P(err)
 
-		// TODO:
-		//   1. refactor this code
-		//   2. make cleanup run period, to avoid the file growup when server long-running
-		err = cleanupExpiredData(
-			time.Duration(conf.Store.DataExpire)*time.Second,
-			db,
-		)
-		dtmimp.E2P(err)
+	// TODO:
+	//   1. refactor this code
+	//   2. make cleanup run period, to avoid the file growup when server long-running
+	err = cleanupExpiredData(
+		time.Duration(dataExpire)*time.Second,
+		db,
+	)
+	dtmimp.E2P(err)
 
-		boltDb = db
-	})
-	return boltDb
+	s.boltDb = db
+	return s
 }
 
 func initializeBuckets(db *bolt.DB) error {
@@ -241,7 +243,7 @@ func (s *Store) Ping() error {
 // PopulateData populates data to boltdb
 func (s *Store) PopulateData(skipDrop bool) {
 	if !skipDrop {
-		err := boltGet().Update(func(t *bolt.Tx) error {
+		err := s.boltDb.Update(func(t *bolt.Tx) error {
 			dtmimp.E2P(t.DeleteBucket(bucketIndex))
 			dtmimp.E2P(t.DeleteBucket(bucketBranches))
 			dtmimp.E2P(t.DeleteBucket(bucketGlobal))
@@ -261,7 +263,7 @@ func (s *Store) PopulateData(skipDrop bool) {
 
 // FindTransGlobalStore finds GlobalTrans data by gid
 func (s *Store) FindTransGlobalStore(gid string) (trans *storage.TransGlobalStore) {
-	err := boltGet().View(func(t *bolt.Tx) error {
+	err := s.boltDb.View(func(t *bolt.Tx) error {
 		trans = tGetGlobal(t, gid)
 		return nil
 	})
@@ -272,7 +274,7 @@ func (s *Store) FindTransGlobalStore(gid string) (trans *storage.TransGlobalStor
 // ScanTransGlobalStores lists GlobalTrans data
 func (s *Store) ScanTransGlobalStores(position *string, limit int64) []storage.TransGlobalStore {
 	globals := []storage.TransGlobalStore{}
-	err := boltGet().View(func(t *bolt.Tx) error {
+	err := s.boltDb.View(func(t *bolt.Tx) error {
 		cursor := t.Bucket(bucketGlobal).Cursor()
 		for k, v := cursor.First(); k != nil; k, v = cursor.Next() {
 			if string(k) == *position {
@@ -299,7 +301,7 @@ func (s *Store) ScanTransGlobalStores(position *string, limit int64) []storage.T
 // FindBranches finds Branch data by gid
 func (s *Store) FindBranches(gid string) []storage.TransBranchStore {
 	var branches []storage.TransBranchStore
-	err := boltGet().View(func(t *bolt.Tx) error {
+	err := s.boltDb.View(func(t *bolt.Tx) error {
 		branches = tGetBranches(t, gid)
 		return nil
 	})
@@ -314,7 +316,7 @@ func (s *Store) UpdateBranches(branches []storage.TransBranchStore, updates []st
 
 // LockGlobalSaveBranches creates branches
 func (s *Store) LockGlobalSaveBranches(gid string, status string, branches []storage.TransBranchStore, branchStart int) {
-	err := boltGet().Update(func(t *bolt.Tx) error {
+	err := s.boltDb.Update(func(t *bolt.Tx) error {
 		g := tGetGlobal(t, gid)
 		if g == nil {
 			return storage.ErrNotFound
@@ -330,7 +332,7 @@ func (s *Store) LockGlobalSaveBranches(gid string, status string, branches []sto
 
 // MaySaveNewTrans creates a new trans
 func (s *Store) MaySaveNewTrans(global *storage.TransGlobalStore, branches []storage.TransBranchStore) error {
-	return boltGet().Update(func(t *bolt.Tx) error {
+	return s.boltDb.Update(func(t *bolt.Tx) error {
 		g := tGetGlobal(t, global.Gid)
 		if g != nil {
 			return storage.ErrUniqueConflict
@@ -346,7 +348,7 @@ func (s *Store) MaySaveNewTrans(global *storage.TransGlobalStore, branches []sto
 func (s *Store) ChangeGlobalStatus(global *storage.TransGlobalStore, newStatus string, updates []string, finished bool) {
 	old := global.Status
 	global.Status = newStatus
-	err := boltGet().Update(func(t *bolt.Tx) error {
+	err := s.boltDb.Update(func(t *bolt.Tx) error {
 		g := tGetGlobal(t, global.Gid)
 		if g == nil || g.Status != old {
 			return storage.ErrNotFound
@@ -366,7 +368,7 @@ func (s *Store) TouchCronTime(global *storage.TransGlobalStore, nextCronInterval
 	global.NextCronTime = dtmutil.GetNextTime(nextCronInterval)
 	global.UpdateTime = dtmutil.GetNextTime(0)
 	global.NextCronInterval = nextCronInterval
-	err := boltGet().Update(func(t *bolt.Tx) error {
+	err := s.boltDb.Update(func(t *bolt.Tx) error {
 		g := tGetGlobal(t, global.Gid)
 		if g == nil || g.Gid != global.Gid {
 			return storage.ErrNotFound
@@ -383,8 +385,8 @@ func (s *Store) TouchCronTime(global *storage.TransGlobalStore, nextCronInterval
 func (s *Store) LockOneGlobalTrans(expireIn time.Duration) *storage.TransGlobalStore {
 	var trans *storage.TransGlobalStore
 	min := fmt.Sprintf("%d", time.Now().Add(expireIn).Unix())
-	next := time.Now().Add(time.Duration(conf.RetryInterval) * time.Second)
-	err := boltGet().Update(func(t *bolt.Tx) error {
+	next := time.Now().Add(time.Duration(s.retryInterval) * time.Second)
+	err := s.boltDb.Update(func(t *bolt.Tx) error {
 		cursor := t.Bucket(bucketIndex).Cursor()
 		for trans == nil {
 			k, v := cursor.First()

dtmsvr/storage/registry/factory.go

@@ -0,0 +1,25 @@
+package registry
+
+import (
+	"sync"
+
+	"github.com/dtm-labs/dtm/dtmsvr/storage"
+)
+
+// SingletonFactory is the factory to build store in SINGLETON pattern.
+type SingletonFactory struct {
+	once sync.Once
+
+	store storage.Store
+
+	creatorFunction func() storage.Store
+}
+
+// GetStorage implement the StorageFactory.GetStorage
+func (f *SingletonFactory) GetStorage() storage.Store {
+	f.once.Do(func() {
+		f.store = f.creatorFunction()
+	})
+
+	return f.store
+}

dtmsvr/storage/registry/registry.go

@@ -12,16 +12,38 @@ import (
 
 var conf = &config.Config
 
-var stores map[string]storage.Store = map[string]storage.Store{
-	"redis":    &redis.Store{},
-	"mysql":    &sql.Store{},
-	"postgres": &sql.Store{},
-	"boltdb":   &boltdb.Store{},
+// StorageFactory is factory to get storage instance.
+type StorageFactory interface {
+	// GetStorage will return the Storage instance.
+	GetStorage() storage.Store
+}
+
+var storeFactorys = map[string]StorageFactory{
+	"boltdb": &SingletonFactory{
+		creatorFunction: func() storage.Store {
+			return boltdb.NewStore(conf.Store.DataExpire, conf.RetryInterval)
+		},
+	},
+	"redis": &SingletonFactory{
+		creatorFunction: func() storage.Store {
+			return &redis.Store{}
+		},
+	},
+	"mysql": &SingletonFactory{
+		creatorFunction: func() storage.Store {
+			return &sql.Store{}
+		},
+	},
+	"postgres": &SingletonFactory{
+		creatorFunction: func() storage.Store {
+			return &sql.Store{}
+		},
+	},
 }
 
 // GetStore returns storage.Store
 func GetStore() storage.Store {
-	return stores[conf.Store.Driver]
+	return storeFactorys[conf.Store.Driver].GetStorage()
 }
 
 // WaitStoreUp wait for db to go up