README
¶
multiredsync
批量版本的 redsync，可以针对一批分布式锁进行Lock/Unlock
Features
- 支持一次性对多个key进行加锁，操作具有原子性（任一未上锁成功则会阻塞等待）
- 拥有和 redsync 相同的使用方式，仅构造方法有锁差异
- 当仅对一个key加锁时，会退化为与 redsync 相同的操作过程（redlock），完全兼容 redsync 的使用场景&性能
Usage
除了初始化方案需要传入多个key以外，其他的使用方式与redsync无二
func main() {
opt := &redis.Options{
Addr: "127.0.0.1:6379",
}
client := redis.NewClient(opt)
redsync := multiredsync.New(goredis.NewPool(client))
mutex := redsync.NewMutex(
[]string{"key1", "key2", "key3", "key4", "key4"},
multiredsync.WithExpiry(8*time.Second),
multiredsync.WithRetryDelay(100*time.Millisecond),
)
if err := mutex.Lock(); err != nil {
panic(err)
}
if ok, err := mutex.Unlock(); !ok || err != nil {
panic("unlock failed")
}
}
Documentation
¶
Index ¶
- Variables
- type DelayFunc
- type ErrNodeTaken
- type ErrTaken
- type MultiRedsync
- type Mutex
- func (m *Mutex) Extend() (bool, error)
- func (m *Mutex) ExtendContext(ctx context.Context) (bool, error)
- func (m *Mutex) Lock() error
- func (m *Mutex) LockContext(ctx context.Context) error
- func (m *Mutex) Names() []string
- func (m *Mutex) TryLock() error
- func (m *Mutex) TryLockContext(ctx context.Context) error
- func (m *Mutex) Unlock() (bool, error)
- func (m *Mutex) UnlockContext(ctx context.Context) (bool, error)
- func (m *Mutex) Until() time.Time
- func (m *Mutex) Value() string
- type Option
- func WithDriftFactor(factor float64) Option
- func WithExpiry(expiry time.Duration) Option
- func WithFailFast(b bool) Option
- func WithGenValueFunc(genValueFunc func() (string, error)) Option
- func WithRetryDelay(delay time.Duration) Option
- func WithRetryDelayFunc(delayFunc DelayFunc) Option
- func WithSetNXOnExtend() Option
- func WithShufflePools(b bool) Option
- func WithTimeoutFactor(factor float64) Option
- func WithTries(tries int) Option
- func WithValue(v string) Option
- type OptionFunc
- type RedisError
Constants ¶
This section is empty.
Variables ¶
var ErrExtendFailed = errors.New("redsync: failed to extend lock")
ErrExtendFailed is the error resulting if Redsync fails to extend the lock.
var ErrFailed = errors.New("redsync: failed to acquire lock")
ErrFailed is the error resulting if Redsync fails to acquire the lock after exhausting all retries.
var ErrLockAlreadyExpired = errors.New("redsync: failed to unlock, lock was already expired")
ErrLockAlreadyExpired is the error resulting if trying to unlock the lock which already expired.
Functions ¶
This section is empty.
Types ¶
type ErrNodeTaken ¶
type ErrNodeTaken struct {
Node int
}
ErrNodeTaken is the error resulting if the lock is already taken in one of the cluster's nodes
func (ErrNodeTaken) Error ¶
func (err ErrNodeTaken) Error() string
type ErrTaken ¶
type ErrTaken struct {
Nodes []int
}
ErrTaken happens when the lock is already taken in a quorum on nodes.
type MultiRedsync ¶
type MultiRedsync struct {
// contains filtered or unexported fields
}
MultiRedsync provides a simple method for creating distributed mutexes using multiple Redis connection pools.
func New ¶
func New(pools ...redis.Pool) *MultiRedsync
New creates and returns a new MultiRedsync instance from given Redis connection pools.
type Mutex ¶
type Mutex struct {
// contains filtered or unexported fields
}
A Mutex is a distributed mutual exclusion lock.
func (*Mutex) ExtendContext ¶
ExtendContext resets the mutex's expiry and returns the status of expiry extension.
func (*Mutex) Lock ¶
Lock locks m. In case it returns an error on failure, you may retry to acquire the lock by calling this method again.
func (*Mutex) LockContext ¶
LockContext locks m. In case it returns an error on failure, you may retry to acquire the lock by calling this method again.
func (*Mutex) TryLock ¶
TryLock only attempts to lock m once and returns immediately regardless of success or failure without retrying.
func (*Mutex) TryLockContext ¶
TryLockContext only attempts to lock m once and returns immediately regardless of success or failure without retrying.
func (*Mutex) UnlockContext ¶
UnlockContext unlocks m and returns the status of unlock.
type Option ¶
type Option interface {
Apply(*Mutex)
}
An Option configures a mutex.
func WithDriftFactor ¶
WithDriftFactor can be used to set the clock drift factor. The default value is 0.01.
func WithExpiry ¶
WithExpiry can be used to set the expiry of a mutex to the given value. The default is 8s.
func WithFailFast ¶
WithFailFast can be used to quickly acquire and release the lock. When some Redis servers are blocking, we do not need to wait for responses from all the Redis servers response. As long as the quorum is met, we can assume the lock is acquired. The effect of this parameter is to achieve low latency, avoid Redis blocking causing Lock/Unlock to not return for a long time.
func WithGenValueFunc ¶
WithGenValueFunc can be used to set the custom value generator.
func WithRetryDelay ¶
WithRetryDelay can be used to set the amount of time to wait between retries. The default value is rand(50ms, 250ms).
func WithRetryDelayFunc ¶
WithRetryDelayFunc can be used to override default delay behavior.
func WithSetNXOnExtend ¶
func WithSetNXOnExtend() Option
WithSetNXOnExtend improves extending logic to extend the key if exist and if not, tries to set a new key in redis Useful if your redises restart often and you want to reduce the chances of losing the lock Read this MR for more info: https://github.com/go-redsync/redsync/pull/149
func WithShufflePools ¶
WithShufflePools can be used to shuffle Redis pools to reduce centralized access in concurrent scenarios.
func WithTimeoutFactor ¶
WithTimeoutFactor can be used to set the timeout factor. The default value is 0.05.
type RedisError ¶
A RedisError is an error communicating with one of the Redis nodes.
func (RedisError) Error ¶
func (e RedisError) Error() string
func (RedisError) Unwrap ¶
func (e RedisError) Unwrap() error
Source Files
Directories