cachelock

Documentation

Index

• Constants
• Variables
• type Lock
• type Locker
  • func New(client cache.Client, expiration time.Duration, retryStrategy RetryStrategy) Locker
• type MockLock
  • func ExpectAcquireAndRelease(locker *MockLocker, key string) *MockLock
  • func NewMockLock() *MockLock
  • func (m *MockLock) Release(ctx context.Context) error
• type MockLocker
  • func NewMockLocker() *MockLocker
  • func (m *MockLocker) Acquire(ctx context.Context, key string) (Lock, error)
• type RetryAttempt
  • func ExponentialBackoff(min, max time.Duration) RetryAttempt
  • func LinearBackoff(backoff time.Duration) RetryAttempt
  • func NoRetry() RetryAttempt
• type RetryStrategy
  • func AttemptBoundRetryStrategy(maxAttempts int, retryStrategy RetryStrategy) RetryStrategy
  • func ExponentialBackoffStrategy(min, max time.Duration) RetryStrategy
  • func LinearBackoffStrategy(backoff time.Duration) RetryStrategy

Constants

const DefaultLockExpiration = time.Minute * 5

Variables

var (
	ErrNotAcquired = errors.New("lock not acquired")
	ErrNotReleased = errors.New("lock not released")
)

var (
	NoRetryStrategy = LinearBackoffStrategy(0)
)

Types

type Lock

type Lock interface {
	Release(context.Context) error
}

Lock is a handle on an acquired lock.

type Locker

type Locker interface {
	Acquire(ctx context.Context, key string) (Lock, error)
}

Locker is a service that provides a lock for a resource.

func New

func New(client cache.Client, expiration time.Duration, retryStrategy RetryStrategy) Locker

type MockLock

type MockLock struct {
	mock.Mock
}

func ExpectAcquireAndRelease

func ExpectAcquireAndRelease(locker *MockLocker, key string) *MockLock

func NewMockLock

func NewMockLock() *MockLock

func (*MockLock) Release

func (m *MockLock) Release(ctx context.Context) error

type MockLocker

type MockLocker struct {
	mock.Mock
}

func NewMockLocker

func NewMockLocker() *MockLocker

func (*MockLocker) Acquire

func (m *MockLocker) Acquire(ctx context.Context, key string) (Lock, error)

type RetryAttempt

type RetryAttempt interface {
	// NextBackoff returns the next backoff duration.
	NextBackoff() time.Duration
}

RetryAttempt allows to customise the lock retry strategy.

func ExponentialBackoff

func ExponentialBackoff(min, max time.Duration) RetryAttempt

ExponentialBackoff strategy is an optimization strategy with a retry time of 2**n milliseconds (n means number of times). You can set a minimum and maximum value, the recommended minimum value is not less than 16ms.

func LinearBackoff

func LinearBackoff(backoff time.Duration) RetryAttempt

LinearBackoff allows retries regularly with customized intervals

func NoRetry

func NoRetry() RetryAttempt

NoRetry acquire the lock only once.

type RetryStrategy

type RetryStrategy func() RetryAttempt

func AttemptBoundRetryStrategy

func AttemptBoundRetryStrategy(maxAttempts int, retryStrategy RetryStrategy) RetryStrategy

func ExponentialBackoffStrategy

func ExponentialBackoffStrategy(min, max time.Duration) RetryStrategy

func LinearBackoffStrategy

func LinearBackoffStrategy(backoff time.Duration) RetryStrategy