README
¶
go-limiter
Go-Limiter is a rate limiter which can throttle up and back requests in a specified situation.
Go-Limiter* can apply to a custom function that revaluates a current limit of the requests in a specified situation but doesn't get out between min and max limit that you set.
Revaluate time happens periodically; of course, it supports a custom interval that you set.
It's based on memory or redis. If you use it in distributed applications, recommend redis.
Getting Started
package main
import (
"time"
"github.com/gjbae1212/go-limiter"
)
func main() {
cache, _ := limiter.NewMemoryCache() // or limiter.NewRedisCache
rateLimiter, _ := limiter.NewRateLimiter("service-name", cache,
limiter.WithEstimatePeriod(10 * time.Minute),
limiter.WithMinLimit(10),
limiter.WithMaxLimit(10000),
)
// ok is true : doesn't exceed limit.
// ok is false : exceed limit.
ok, _ := rateLimiter.Acquire()
}
LICENSE
This project is following The MIT.
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( ErrInvalidParams = errors.New("[err] invalid params") ErrUnknown = errors.New("[err] unknown") )
Functions ¶
This section is empty.
Types ¶
type Cache ¶
type Cache interface {
Get(key string) (interface{}, bool, error)
MGet(keys ...string) ([]interface{}, bool, error)
Set(key string, value interface{}, ttl time.Duration) error
Increment(key string, n int64, ttl time.Duration) error
Ping(ctx context.Context) bool
Close() error
}
Cache is an interface which supports fundamental functionality for storage. This is used by RateLimiter.
func NewRedisCache ¶
NewRedisCache returns cache for redis
type ErrorHandler ¶
type ErrorHandler func(error)
type Option ¶
type Option interface {
// contains filtered or unexported methods
}
Option is an interface for dependency injection.
type OptionFunc ¶
type OptionFunc func(l *limiter)
OptionFunc is a function for Option interface.
func WithErrorHandler ¶
func WithErrorHandler(h ErrorHandler) OptionFunc
WithErrorHandler returns a function which sets handler to process error.
func WithEstimatePeriod ¶
func WithEstimatePeriod(d time.Duration) OptionFunc
WithEstimatePeriod returns a function which sets a period to estimate threshold.
func WithMaxLimit ¶
func WithMaxLimit(max int64) OptionFunc
WithMaxLimit returns a function which sets maximum limit per minute in limiter.
func WithMinLimit ¶
func WithMinLimit(min int64) OptionFunc
WithMinLimit returns a function which sets minimum limit per minute in limiter.
func WithRevaluateLimit ¶
func WithRevaluateLimit(f RevaluateLimit) OptionFunc
WithRevaluateLimit returns a function which sets function used to revaluate limit.
type RateLimiter ¶
type RateLimiter interface {
Acquire() (bool, error)
CurrentLimit() (int64, error)
HealthCheck(ctx context.Context) bool
Close() error
}
func NewRateLimiter ¶
func NewRateLimiter(serviceName string, cache Cache, opts ...Option) (RateLimiter, error)
NewRateLimiter returns RateLimiter interface.
type RevaluateLimit ¶
type RevaluateLimit func(currentlyLimit, estimatedTimeWindowSize, estimatedTimeWindowUsedCount int64) int64
RevaluateLimit is to revaluate sending limit per 1 minute. currentlyLimit is currently applied limit. estimatedTimeWindowSize is the size of time-window for the duration of an estimated period. estimatedTimeWindowUsedCount is the sum of sending push count of time-window for the duration of an estimated period. Its return value is new limit per 1 minute.
Source Files