ratelimiter

Documentation

Index

• Constants
• type Event
• type EventListenerFunc
• type Policy
  • func NewDefaultPolicy() *Policy
  • func NewPolicy(timeout, refresh time.Duration, limit int) *Policy
• type RateLimiter
  • func New(policy *Policy) *RateLimiter
  • func (rl *RateLimiter) AcquirePermission() (bool, time.Duration)
  • func (rl *RateLimiter) SetState(state State)
  • func (rl *RateLimiter) SetStateListener(listener EventListenerFunc)
  • func (rl *RateLimiter) WaitPermission() bool
• type State

Constants

const (
	StateNormal = iota
	StateLimiting
	StateDisabled
)

circuit breaker states

Types

type Event

type Event struct {
	Time  time.Time
	State string
}

Event defines the event of rate limiter

type EventListenerFunc

type EventListenerFunc func(event *Event)

EventListenerFunc is a listener function to listen state transit event

type Policy

type Policy struct {
	TimeoutDuration    time.Duration
	LimitRefreshPeriod time.Duration
	LimitForPeriod     int
}

Policy defines the policy of a rate limiter

func NewDefaultPolicy

func NewDefaultPolicy() *Policy

NewDefaultPolicy create and initialize a policy with default configuration

func NewPolicy

func NewPolicy(timeout, refresh time.Duration, limit int) *Policy

NewPolicy create and initialize a policy

type RateLimiter

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

RateLimiter defines a rate limiter

func New

func New(policy *Policy) *RateLimiter

New creates a rate limiter based on `policy`,

func (*RateLimiter) AcquirePermission

func (rl *RateLimiter) AcquirePermission() (bool, time.Duration)

AcquirePermission acquires a permission from the rate limiter. returns true if the request is permitted and false otherwise. when permitted, the caller should wait returned duration before action.

func (*RateLimiter) SetState

func (rl *RateLimiter) SetState(state State)

SetState sets the state of the rate limiter to `state`

func (*RateLimiter) SetStateListener

func (rl *RateLimiter) SetStateListener(listener EventListenerFunc)

SetStateListener sets a state listener for the RateLimiter

func (*RateLimiter) WaitPermission

func (rl *RateLimiter) WaitPermission() bool

WaitPermission waits a permission from the rate limiter returns true if the request is permitted and false if timed out

type State

type State uint8

State is rate limiter state