go_redislock

README

go-redislock

a distributed redis lock usable in a production environment implemented in Go

• 中文

How To Use

• Pull codes

  go get github.com/hedon954/go-redislock
  

  import (
  	...
  	redislock "github.com/hedon954/go-redislock"
  	...
  )
  

• Init Client

  yourRedisClient := ...
  c := redislock.NewCliengt(yourRedisClient)
  

• Prepare arguments according to your real business needs and call Lock() or TryLock()

  c.Lock(...)
  c.TryLock(...)
  

• If the concurrency is high, you can use the 'SingleFlightLock()' method to optimize the performance of distributed locks

  c.SingleLightLock(...)
  

Implementation Cores

• core: SETNX
• refresh expiration
• retry while outtime
• singleflight

Documentation

Index

• Variables
• type Client
  • func NewClient(c redis.Cmdable) *Client
  • func (c *Client) Lock(ctx context.Context, key string, expiration, timeout time.Duration, ...) (*Lock, error)
  • func (c *Client) SingleFlightLock(ctx context.Context, key string, expiration, timeout time.Duration, ...) (*Lock, error)
  • func (c *Client) TryLock(ctx context.Context, key string, expiration time.Duration) (*Lock, error)
• type FixIntervalRetry
  • func (f *FixIntervalRetry) Next() (time.Duration, bool)
• type Lock
  • func (l *Lock) AutoRefresh(interval time.Duration, timeout time.Duration) error
  • func (l *Lock) Refresh(ctx context.Context) error
  • func (l *Lock) UnLock(ctx context.Context) error
• type RetryStrategy

Variables

var (
	ErrLockFailed  = errors.New("lock failed")
	ErrLockNotHold = errors.New("not hold current lock")
)

Types

type Client

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

Client is a client held redis client

func NewClient

func NewClient(c redis.Cmdable) *Client

NewClient creates a new client

func (*Client) Lock

func (c *Client) Lock(ctx context.Context, key string, expiration, timeout time.Duration, retry RetryStrategy) (*Lock, error)

Lock locks

func (*Client) SingleFlightLock

func (c *Client) SingleFlightLock(ctx context.Context, key string, expiration, timeout time.Duration, retry RetryStrategy) (*Lock, error)

SingleFlightLock uses singleFlight to reduce stress in high concurrency situations

func (*Client) TryLock

func (c *Client) TryLock(ctx context.Context, key string, expiration time.Duration) (*Lock, error)

TryLock trys to hold a lock

type FixIntervalRetry

type FixIntervalRetry struct {
	Interval time.Duration // retry interval
	Max      int           // max retry times
	// contains filtered or unexported fields
}

FixIntervalRetry is a fix interval retry strategy

func (*FixIntervalRetry) Next

func (f *FixIntervalRetry) Next() (time.Duration, bool)

type Lock

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

Lock is a lock created after client locks successfully

func (*Lock) AutoRefresh

func (l *Lock) AutoRefresh(interval time.Duration, timeout time.Duration) error

AutoRefresh always refreshes lock's expiration automatically

func (*Lock) Refresh

func (l *Lock) Refresh(ctx context.Context) error

Refresh refreshes lock's expiration

func (*Lock) UnLock

func (l *Lock) UnLock(ctx context.Context) error

UnLock unlocks

type RetryStrategy

type RetryStrategy interface {

	// Next
	//	first return means the interval of the next retry
	//	second return means need to retry or not
	Next() (time.Duration, bool)
}

RetryStrategy defines retry strategy