enable truncate value log option if badger db offset is different from badger db size (#128)

* enable truncate option in badger to cleanup inconsistent data due to application crashes

* updated as per review comments

pkg/sloop/server/internal/config/config.go

@@ -69,6 +69,7 @@ type SloopConfig struct {
 	BadgerNumL0TablesStall   int           `json:"badgerNumLevelZeroTables"`
 	BadgerSyncWrites         bool          `json:"badgerSyncWrites"`
 	BadgerVLogFileIOMapping  bool          `json:"badgerVLogFileIOMapping"`
+	BadgerVLogTruncate       bool          `json:"badgerVLogTruncate"`
 	EnableDeleteKeys         bool          `json:"enableDeleteKeys"`
 }
 
@@ -115,6 +116,7 @@ func registerFlags(fs *flag.FlagSet, config *SloopConfig) {
 	fs.BoolVar(&config.BadgerSyncWrites, "badger-sync-writes", true, "Sync Writes ensures writes are synced to disk if set to true")
 	fs.BoolVar(&config.EnableDeleteKeys, "enable-delete-keys", false, "Use delete prefixes instead of dropPrefix for GC")
 	fs.BoolVar(&config.BadgerVLogFileIOMapping, "badger-vlog-fileIO-mapping", false, "Indicates which file loading mode should be used for the value log data, in memory constrained environments the value is recommended to be true")
+	fs.BoolVar(&config.BadgerVLogTruncate, "badger-vlog-truncate", true, "Truncate value log if badger db offset is different from badger db size")
 }
 
 // This will first check if a config file is specified on cmd line using a temporary flagSet

pkg/sloop/server/server.go

@@ -73,6 +73,7 @@ func RealMain() error {
 		BadgerLevelOneSize:       conf.BadgerLevelOneSize,
 		BadgerLevSizeMultiplier:  conf.BadgerLevSizeMultiplier,
 		BadgerVLogFileIOMapping:  conf.BadgerVLogFileIOMapping,
+		BadgerVLogTruncate:       conf.BadgerVLogTruncate,
 	}
 	db, err := untyped.OpenStore(factory, storeConfig)
 	if err != nil {

pkg/sloop/store/untyped/store.go

@@ -9,7 +9,7 @@ package untyped
 
 import (
 	"fmt"
-	badger "github.com/dgraph-io/badger/v2"
+	"github.com/dgraph-io/badger/v2"
 	"github.com/dgraph-io/badger/v2/options"
 	"github.com/golang/glog"
 	"github.com/salesforce/sloop/pkg/sloop/store/untyped/badgerwrap"
@@ -33,6 +33,7 @@ type Config struct {
 	BadgerLevelOneSize       int64
 	BadgerLevSizeMultiplier  int
 	BadgerVLogFileIOMapping  bool
+	BadgerVLogTruncate       bool
 }
 
 func OpenStore(factory badgerwrap.Factory, config *Config) (badgerwrap.DB, error) {
@@ -94,6 +95,8 @@ func OpenStore(factory badgerwrap.Factory, config *Config) (badgerwrap.DB, error
 		opts = opts.WithValueLogLoadingMode(options.FileIO)
 	}
 
+	opts = opts.WithTruncate(config.BadgerVLogTruncate)
+
 	opts = opts.WithSyncWrites(config.BadgerSyncWrites)
 
 	db, err := factory.Open(opts)