rerate

README

rerate

rerate is a redis-based ratecounter and ratelimiter

• Dead simple api
• With redis as backend, multiple rate counters/limiters can work as a cluster
• Count/Limit requests any period, 2 day, 1 hour, 5 minute or 2 second, it's up to you
• Recording requests as a histotram, which can be used to visualize or monitor
• Limit requests from single ip, userid, applicationid, or any other unique identifier

Tutorial

package main

import (
    "github.com/abo/rerate"
)

...

func main() {
    pool := newRedisPool("localhost:6379", "")
    
    // Counter
    counter := rerate.NewCounter(pool, "rl:test", 10 * time.Minute, 15 * time.Second)
    counter.Inc("click")
    c, err := counter.Count("click")
    
    // Limiter
    limiter := rerate.NewLimiter(pool, "rl:test", 1 * time.Hour, 15 * time.Minute, 100)
    limiter.Inc("114.255.86.200")
    rem, err := limiter.Remaining("114.255.86.200")
    exceed, err := limiter.Exceeded("114.255.86.200")
}

Installation

Install rerate using the "go get" command:

go get github.com/abo/rerate

Documentation

• API Reference
• Wiki

Contributing

WELCOME

License

rerate is available under the The MIT License (MIT).

Documentation

Index

• type Counter
  • func NewCounter(pool Pool, prefix string, period, interval time.Duration) *Counter
  • func (c *Counter) Count(id string) (int64, error)
  • func (c *Counter) Histogram(id string) ([]int64, error)
  • func (c *Counter) Inc(id string) error
  • func (c *Counter) Reset(id string) error
• type Limiter
  • func NewLimiter(pool Pool, pfx string, period, interval time.Duration, max int64) *Limiter
  • func (l *Limiter) Exceeded(id string) (bool, error)
  • func (l *Limiter) Remaining(id string) (int64, error)
• type Pool

Types

type Counter

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

Counter count total occurs during a period, it will store occurs during every time slice interval: (now ~ now - intervl), (now - intervl ~ now - 2*intervl)...

func NewCounter

func NewCounter(pool Pool, prefix string, period, interval time.Duration) *Counter

NewCounter create a new Counter

func (*Counter) Count

func (c *Counter) Count(id string) (int64, error)

Count return total occurs in recent period

func (*Counter) Histogram

func (c *Counter) Histogram(id string) ([]int64, error)

Histogram return count histogram in recent period, order by time desc

func (*Counter) Inc

func (c *Counter) Inc(id string) error

Inc increment id's occurs with current timestamp, the count before period will be cleanup

func (*Counter) Reset

func (c *Counter) Reset(id string) error

Reset cleanup occurs, set it to zero

type Limiter

type Limiter struct {
	Counter
	// contains filtered or unexported fields
}

Limiter a redis-based ratelimiter

func NewLimiter

func NewLimiter(pool Pool, pfx string, period, interval time.Duration, max int64) *Limiter

NewLimiter create a new redis-based ratelimiter the Limiter limits the rate to max times per period

func (*Limiter) Exceeded

func (l *Limiter) Exceeded(id string) (bool, error)

Exceeded is exceeded the rate limit or not

func (*Limiter) Remaining

func (l *Limiter) Remaining(id string) (int64, error)

Remaining return the number of requests left for the time window

type Pool

type Pool interface {
	Get() redis.Conn
}

Pool maintains a pool of connections. The application calls the Get method to get a connection from the pool and the connection's Close method to return the connection's resources to the pool.