postgres

Documentation

Index

• type Locker
  • func NewLocker(db *sql.DB) *Locker
  • func (r *Locker) Get(ctx context.Context, key string) (locker.Lock, error)
  • func (r *Locker) GetByRawKey(ctx context.Context, keyA, keyB int32) (locker.Lock, error)

Types

type Locker

type Locker struct {
	Logger locker.Logger

	Hash32A func() hash.Hash32
	Hash32B func() hash.Hash32
	// contains filtered or unexported fields
}

Locker is an implementation of the locker.Locker using PostgreSQL pg_advisory_lock

func NewLocker

func NewLocker(db *sql.DB) *Locker

NewLocker creates a new Locker

func (*Locker) Get

func (r *Locker) Get(ctx context.Context, key string) (locker.Lock, error)

Get calls PostgreSQL pg_advisory_lock(keyA int, keyB int) to acquire the lock. Since these pg_advisory_lock keys are 32-bit integers, this method uses two different hash functions to convert the argument string keys to integers and uses them as the keys for pg_advisory_lock. Default hash functions are FNV-1a hash and Murmur hash.

func (*Locker) GetByRawKey

func (r *Locker) GetByRawKey(ctx context.Context, keyA, keyB int32) (locker.Lock, error)

GetByRawKey calls PostgreSQL pg_advisory_lock(keyA int, keyB int) to acquire the lock.