type Backoff struct {
sync.RWMutex
Clock clock.Clock
// contains filtered or unexported fields
}
func NewBackOff(initial, max time.Duration) *Backoff
func NewBackOffWithJitter(initial, max time.Duration, maxJitterFactor float64) *Backoff
func NewFakeBackOff(initial, max time.Duration, tc *testingclock.FakeClock) *Backoff
func NewFakeBackOffWithJitter(initial, max time.Duration, tc *testingclock.FakeClock, maxJitterFactor float64) *Backoff
func (p *Backoff) DeleteEntry(id string)
func (p *Backoff) GC()
Garbage collect records that have aged past maxDuration. Backoff users are expected to invoke this periodically.
func (p *Backoff) Get(id string) time.Duration
Get the current backoff Duration
func (p *Backoff) IsInBackOffSince(id string, eventTime time.Time) bool
Returns True if the elapsed time since eventTime is smaller than the current backoff window
func (p *Backoff) IsInBackOffSinceUpdate(id string, eventTime time.Time) bool
Returns True if time since lastupdate is less than the current backoff window.
func (p *Backoff) Next(id string, eventTime time.Time)
move backoff to the next mark, capping at maxDuration
func (p *Backoff) Reset(id string)
Reset forces clearing of all backoff data for a given key.
An injectable, mockable clock interface.
type Clock interface {
clock.PassiveClock
Sleep(time.Duration)
}
type PassiveRateLimiter interface {
// TryAccept returns true if a token is taken immediately. Otherwise,
// it returns false.
TryAccept() bool
// Stop stops the rate limiter, subsequent calls to CanAccept will return false
Stop()
// QPS returns QPS of this rate limiter
QPS() float32
}
func NewTokenBucketPassiveRateLimiter(qps float32, burst int) PassiveRateLimiter
NewTokenBucketPassiveRateLimiter is similar to NewTokenBucketRateLimiter except that it returns a PassiveRateLimiter which does not have Accept() and Wait() methods.
func NewTokenBucketPassiveRateLimiterWithClock(qps float32, burst int, c clock.PassiveClock) PassiveRateLimiter
NewTokenBucketPassiveRateLimiterWithClock is similar to NewTokenBucketRateLimiterWithClock except that it returns a PassiveRateLimiter which does not have Accept() and Wait() methods and uses a PassiveClock.
type RateLimiter interface {
PassiveRateLimiter
// Accept returns once a token becomes available.
Accept()
// Wait returns nil if a token is taken before the Context is done.
Wait(ctx context.Context) error
}
func NewFakeAlwaysRateLimiter() RateLimiter
func NewFakeNeverRateLimiter() RateLimiter
func NewTokenBucketRateLimiter(qps float32, burst int) RateLimiter
NewTokenBucketRateLimiter creates a rate limiter which implements a token bucket approach. The rate limiter allows bursts of up to 'burst' to exceed the QPS, while still maintaining a smoothed qps rate of 'qps'. The bucket is initially filled with 'burst' tokens, and refills at a rate of 'qps'. The maximum number of tokens in the bucket is capped at 'burst'.
func NewTokenBucketRateLimiterWithClock(qps float32, burst int, c Clock) RateLimiter
NewTokenBucketRateLimiterWithClock is identical to NewTokenBucketRateLimiter but allows an injectable clock, for testing.