badger

Documentation

Index

• Constants
• Variables
• func InstanceDir(dataDir, instanceId string) string
• func Open(instancePath string) (*badger.DB, error)
• type BatchedWriter
  • func NewBatchedWriter(db *badger.DB, d time.Duration) *BatchedWriter
  • func (bw *BatchedWriter) Close()
  • func (bw *BatchedWriter) Set(k, v []byte, cb WriteBatchCommitCB) error
  • func (bw *BatchedWriter) SetEntry(e *badger.Entry, cb WriteBatchCommitCB) error
  • func (bw *BatchedWriter) WriteKVList(kvList *pb.KVList, cb WriteBatchCommitCB) error
• type DirectoryLockGuard
  • func AcquireDirectoryLock(dirPath string, pidFileName string, readOnly bool) (*DirectoryLockGuard, error)
  • func (guard *DirectoryLockGuard) Release() error
• type WriteBatch
  • func NewWriteBatch(db *badger.DB) *WriteBatch
  • func (wb *WriteBatch) Cancel()
  • func (wb *WriteBatch) Delete(k []byte, cb WriteBatchCommitCB) error
  • func (wb *WriteBatch) Error() error
  • func (wb *WriteBatch) Flush() error
  • func (wb *WriteBatch) Set(k, v []byte, cb WriteBatchCommitCB) error
  • func (wb *WriteBatch) SetEntry(e *badger.Entry, cb WriteBatchCommitCB) error
  • func (wb *WriteBatch) SetMaxPendingTxns(max int)
• type WriteBatchCommitCB

Constants

const (
	LockFile = "LOCK"
)

Variables

var InitCommitCBsCapacity = 2000

Functions

func InstanceDir

func InstanceDir(dataDir, instanceId string) string

func Open

func Open(instancePath string) (*badger.DB, error)

Types

type BatchedWriter

type BatchedWriter struct {
	// contains filtered or unexported fields
}

func NewBatchedWriter

func NewBatchedWriter(db *badger.DB, d time.Duration) *BatchedWriter

func (*BatchedWriter) Close

func (bw *BatchedWriter) Close()

func (*BatchedWriter) Set

func (bw *BatchedWriter) Set(k, v []byte, cb WriteBatchCommitCB) error

func (*BatchedWriter) SetEntry

func (bw *BatchedWriter) SetEntry(e *badger.Entry, cb WriteBatchCommitCB) error

func (*BatchedWriter) WriteKVList

func (bw *BatchedWriter) WriteKVList(kvList *pb.KVList, cb WriteBatchCommitCB) error

type DirectoryLockGuard

type DirectoryLockGuard struct {
	// contains filtered or unexported fields
}

DirectoryLockGuard holds a lock on a directory and a pid file inside. The pid file isn't part of the locking mechanism, it's just advisory.

func AcquireDirectoryLock

func AcquireDirectoryLock(dirPath string, pidFileName string, readOnly bool) (
	*DirectoryLockGuard, error)

AcquireDirectoryLock gets a lock on the directory (using flock). If this is not read-only, it will also write our pid to dirPath/pidFileName for convenience.

func (*DirectoryLockGuard) Release

func (guard *DirectoryLockGuard) Release() error

Release deletes the pid file and releases our lock on the directory.

type WriteBatch

type WriteBatch struct {
	sync.Mutex
	// contains filtered or unexported fields
}

WriteBatch holds the necessary info to perform batched writes.

func NewWriteBatch

func NewWriteBatch(db *badger.DB) *WriteBatch

NewWriteBatch creates a new WriteBatch. This provides a way to conveniently do a lot of writes, batching them up as tightly as possible in a single transaction and using callbacks to avoid waiting for them to commit, thus achieving good performance. This API hides away the logic of creating and committing transactions. Due to the nature of SSI guaratees provided by Badger, blind writes can never encounter transaction conflicts (ErrConflict).

func (*WriteBatch) Cancel

func (wb *WriteBatch) Cancel()

Cancel function must be called if there's a chance that Flush might not get called. If neither Flush or Cancel is called, the transaction oracle would never get a chance to clear out the row commit timestamp map, thus causing an unbounded memory consumption. Typically, you can call Cancel as a defer statement right after NewWriteBatch is called.

Note that any committed writes would still go through despite calling Cancel.

func (*WriteBatch) Delete

func (wb *WriteBatch) Delete(k []byte, cb WriteBatchCommitCB) error

Delete is equivalent of Txn.Delete.

func (*WriteBatch) Error

func (wb *WriteBatch) Error() error

Error returns any errors encountered so far. No commits would be run once an error is detected.

func (*WriteBatch) Flush

func (wb *WriteBatch) Flush() error

Flush must be called at the end to ensure that any pending writes get committed to Badger. Flush returns any error stored by WriteBatch.

func (*WriteBatch) Set

func (wb *WriteBatch) Set(k, v []byte, cb WriteBatchCommitCB) error

Set is equivalent of Txn.Set().

func (*WriteBatch) SetEntry

func (wb *WriteBatch) SetEntry(e *badger.Entry, cb WriteBatchCommitCB) error

SetEntry is the equivalent of Txn.SetEntry.

func (*WriteBatch) SetMaxPendingTxns

func (wb *WriteBatch) SetMaxPendingTxns(max int)

SetMaxPendingTxns sets a limit on maximum number of pending transactions while writing batches. This function should be called before using WriteBatch. Default value of MaxPendingTxns is 16 to minimise memory usage.

type WriteBatchCommitCB

type WriteBatchCommitCB func(error)