axiaoxin-com / ratelimiter

token bucket ratelimiter for nginx-lua/go/gin-middleware

ratelimiter

中文 README

Simple version implementation of token bucket request frequency limiting.

ratelimiter library that supports in-memory and distributed eventually consistent redis stores (includes Gin middleware)

• lua-ngx-ratelimiter: a token bucket frequency limiting implementation of lua + nginx + redis
• MemRatelimiter: a process memory limiter implemented with rate + go-cache
• RedisRatelimiter: a distributed limiter implemented with redis + lua
• GinMemRatelimiter: encapsulating the MemRatelimiter as a gin middleware
• GinRedisRatelimiter: encapsulating the RedisRatelimiter as a gin middleware

Go PKG Installation

go get -u github.com/axiaoxin-com/ratelimiter

Gin Middleware Example

GinMemRatelimiter

package main

import (
	"time"

	"github.com/axiaoxin-com/ratelimiter"
	"github.com/gin-gonic/gin"
)

func main() {
	r := gin.New()
	// Put a token into the token bucket every 1s
	// Maximum 1 request allowed per second
	r.Use(ratelimiter.GinMemRatelimiter(ratelimiter.GinRatelimiterConfig{
		// config: how to generate a limit key
		LimitKey: func(c *gin.Context) string {
			return c.ClientIP()
		},
		// config: how to respond when limiting
		LimitedHandler: func(c *gin.Context) {
			c.JSON(200, "too many requests!!!")
			c.Abort()
			return
		},
		// config: return ratelimiter token fill interval and bucket size
		TokenBucketConfig: func(*gin.Context) (time.Duration, int) {
			return time.Second * 1, 1
		},
	}))
	r.GET("/", func(c *gin.Context) {
		c.JSON(200, "hi")
	})
	r.Run()
}

GinRedisRatelimiter

package main

import (
	"time"

	"github.com/axiaoxin-com/goutils"
	"github.com/axiaoxin-com/ratelimiter"
	"github.com/gin-gonic/gin"
	"github.com/go-redis/redis/v8"
)

func main() {
	r := gin.New()
	// Put a token into the token bucket every 1s
	// Maximum 1 request allowed per second
	rdb, err := goutils.NewRedisClient(&redis.Options{})
	if err != nil {
		panic(err)
	}
	r.Use(ratelimiter.GinRedisRatelimiter(rdb, ratelimiter.GinRatelimiterConfig{
		// config: how to generate a limit key
		LimitKey: func(c *gin.Context) string {
			return c.ClientIP()
		},
		// config: how to respond when limiting
		LimitedHandler: func(c *gin.Context) {
			c.JSON(200, "too many requests!!!")
			c.Abort()
			return
		},
		// config: return ratelimiter token fill interval and bucket size
		TokenBucketConfig: func(*gin.Context) (time.Duration, int) {
			return time.Second * 1, 1
		},
	}))
	r.GET("/", func(c *gin.Context) {
		c.JSON(200, "hi")
	})
	r.Run()
}

Ratelimiter can be directly used in golang program. Examples:

MemRatelimiter

package main

import (
	"context"
	"fmt"
	"time"

	"github.com/axiaoxin-com/ratelimiter"
)

func main() {
	limiter := ratelimiter.NewMemRatelimiter()
	limitKey := "uniq_limit_key"
	tokenFillInterval := time.Second * 1
	bucketSize := 1
	for i := 0; i < 3; i++ {
		// 1st and 3nd is allowed
		if i == 2 {
			time.Sleep(time.Second * 1)
		}
		isAllow := limiter.Allow(context.TODO(), limitKey, tokenFillInterval, bucketSize)
		fmt.Println(i, time.Now(), isAllow)
	}
}

RedisRatelimiter

package main

import (
	"context"
	"fmt"
	"time"

	"github.com/axiaoxin-com/goutils"
	"github.com/axiaoxin-com/ratelimiter"
	"github.com/go-redis/redis/v8"
)

func main() {
	rdb, err := goutils.NewRedisClient(&redis.Options{})
	if err != nil {
		panic(err)
	}

	limiter := ratelimiter.NewRedisRatelimiter(rdb)
	limitKey := "uniq_limit_key"
	tokenFillInterval := time.Second * 1
	bucketSize := 1
	for i := 0; i < 3; i++ {
		// 1st and 3nd is allowed
		if i == 2 {
			time.Sleep(time.Second * 1)
		}
		isAllow := limiter.Allow(context.TODO(), limitKey, tokenFillInterval, bucketSize)
		fmt.Println(i, time.Now(), isAllow)
	}
}